Now until Father’s Day, we are running a sale on all of our Maker Kits.
Get one for Dad AND you, so you can build them together! Buy two and get 50% off the second one.
Available are our new Wasply PFS Maker Kit and our aluminum core (advanced) Alugator Maker Kit.
Use coupon code: popday2014
Been a little while since I’ve posted a Metro Made, so there is no reason why NOT to post one. Fresh from the laser cutter to your workshop, this is a tutorial on how to assemble and finish your Wasply PFS Maker Kit. Don’t have one? You can get yours here: Wasply PFS Maker Kit
In the kit, you’ll have two cores, and two sets of palm swells.
First things first, glue up the core, and two palm swells.
When they are set up, I used a belt sander to start to shape the palm swells. This make life a lot easier later if you take off the bulk of the material first.
Once the swells are partial shaped, time to glue up the swells on the body core.
I used a spindle sander to remove the laser burned wood but this can be done with files and sandpaper.
A round file expands and refines the band grooves.
A few more swipes with a first cut file and the inside of the forks is cleaned up.
The hardest part of the build is shaping the palm swells so they are perfectly round. I used the belt sander again, rotating it like a drum stick. Rasps, files and sandpaper will do the same job.
Using some 100 grit nail files, the palm swell is blended into the core, making a seamless joint.
An optional machining step is to cut some scallops with a big 3″ drum into the finger grip area, but this can be done with a 1/2″ round file.
Now to finish it! A variety of 100 grit, 320 grit foam blocks and a final swipe with some steel wool to prep the surface for clear coat or oil.
The one on the left is one designed by Magpie Slingshots and I replicated it to test out the scale. We worked in collaboration to come to the final design of the Wasply PFS.
After a couple of coats of clear and some light buffing with the wool to get it a more matte finish, the Wasply PFS is done!
Thanks for reading and in case you missed it, you can get your Wasply PFS Maker kit at our store.
Working with an existing aluminum frame that is already structurally sound has a number of benefits, less time spend in beefing up the forks, less worry about the whole thing collapsing in the middle, but the biggest benefit is being able to concentrate on the adornments; the wood. In this Metro Made, I look at expanding and combining a number of methods and methodologies to our aluminum Capuchin frame.
I only ever made one other slingshot with a palm swell and I wasn’t too pleased with it yet it still looked and functioned well. Over the past little while, I have been really paying attention to how I hold a slingshot and my primary grip is actually focused on the pinching of the frame with my index finger and thumb with the slingshot being held back by my pinky looped into the pinky hole (hence the name). This way, I can keep an archer’s loose grip while still maintaining an accurate sight picture when aiming.
This precipitated a couple of things when I was using some heavier band sets (looped 1745), the pressure built up on the finger and thumb area was pretty high and I was pinching way too hard to compensate for it. I wanted to explore another means to lock my hand in more natural position and still be able to use heavier bands. I found that the hollow of my palm was empty when shooting with the MGG Alugator, so it was time to fill in the hollow so the pressure would be evenly distributed through the hand, or at least part of it. The palm swell would require a thicker lamination of woods and to keep it stylist and Metro Grade, it’s only fair that I use some techniques I learned from making the Turkey Shuckapow!.
Here I am mentally planning out that needs to go where.
Two thickness of Black Walnut and a top layer of Paduak with Maple veneer spacers in between each layer making up the palm swell side. The other ‘scale’ is made up of purple heart, paduak with cherry and walnut veneers on top.
Prepping the surface of the 6061 Aluminum frame, removing the marking ink and otherwise natural face.
After some time, the scales where unclamped and the edges that aren’t accessible from the outside of the slingshot are sanded so to reveal the shape and colour.
Here is a shot of the full thickness of the materials, there is a lot of sculpting and wood removal to be done to make this work.
With the scales taped on, the edges of the scales and the frame are sanded together. Next time I am going to make some temporary pins to hold them in place, since the frame heats up from the friction causing the tape to become soft.
After that, the scales are taped together to smooth out the transitions from the scoops to the nubbin shapes.
Time to work on the palm swell. First I used the belt sander to mow down the top layer into a gentle slope. From there I rocked it back to curve the lower portion and also rolled the tips of the scales into a curved nubbin.
It was hard to take photos while working this section since it’s something that is requires a lot of micro sanding operations, slowly taking off material, checking, taking more off, checking again. Eventually the main scallops where taken off.
The ‘waist’ area had the biggest scallops since that where the middle and ring finger wrap around. Thinning around that area makes for a positive yet loose grip. The back side scale is also scalloped in the same way. I want to note that the scallop was done on the yoke area purely for aesthetics, as the routed edge didn’t really match the chamfered edges well.
After placing the scales on the frame, I noticed that the finger/thumb areas were too beefy.
…causing me to stretch to get around the grip.
The answer was scalloping the finger/thumb grip to reduce the travel for my hands. It is at this point, I noticed the face that came out of the woodwork, and the name came to me. Red Fox…or Vulpes.
It was time to brand the beast.
Lots of sanding, 100, 240, 600, steel wool.
I prematurely hit the scales with clear coat to see the grain and colour. The contrasty light in the paint booth makes for a terrible shot.
After some time, I swiped the surface with steel wool to knock down the sheen.
Testing the grip area.
Aluminum bleeds a lot when you sand it, but who ever said making things was a clean job? No one that’s who.
After mixing up some epoxy and fitting some 1/8″ aluminum tubing into the holes, it was time to glue the scales on.
Thanks for reading again and find us on Facebook & Twitter (@MetroGradeGoods)
-Stay True-
-Eric
Random gifts are the best. I got a call from Greyhound saying I had a package to pick up from a friend. Don’t know what wood it is, but it sure is a looker! Also in the video, a look at our newest Aluminum frames, how I treated them and some other materials I recently picked up.
The shop was kind enough to send me a photograph of the frames being cut, I love action shots like this.
Previously we had made the Flatland Flame for Prairie Fire‘s annual fundraiser, Speaking Volumes, and we promised to make two for them. In this short, but sweet post of Metro Made, we look at how we made the Wordsmith, a Scrabble™ themed slinger!
Much like any other Metro Grade slinger, it starts with a core, some lamination layers and the ever important outside face. Here you can see the maple game squares being cut out.
I wanted this to have a little pop on all angles and much like the Tukey SHUCKAPOW!, there is a layer of Purple Heart on both sides of the core sandwiching some contrasting veneers. The rose wood underneath is going to be used for the tips.
After glueing, clamping and sanding the edges, it was back to the laser to etch on the M, G and the G and their letter scores.
Tadah! The nerdiest slingshot of all time! Too bad MGG wouldn’t actually count as a word.
On the back side, a cherry face was carefully selected to have a symmetrical grain so that the rings matched up with the graphics and lettering.
Soon after, routing the edges, contact sanding the scallops and lots of hand sanding, it was paint booth time.
….and the final result! This will be banded up with some 1/4 surgical tubing and it’s off to the event!
In case you didn’t see the Flatland Flame, here is it.
We hope these slings bring in a lot to support the best local magazine around these parts.
Thanks for reading.
-Stay True-
_Eric
Now till May 16th, 2014 you can get all your bands and pouches ready for outdoor shooting for 25% off.
This includes our newly listed Theraband Gold available in 5 ft and 10 ft bundles.
Use code: springback2014
-Eric
Shops that have skunkworks devisions will always try new things, one offs, tests and prototypes that often lead to very possible production ideas. In this ‘skunkworks’ post, I try to do a few things differently that will definitely make its way into some production slingshots.
It’s much easier to test something when you have a solid frame to work on, quite literally. I took our SHUCKAPOW design and made up a 1/4″ Baltic Birch plywood core. From there, it was some quick work since the spacer veneers in between the layers would curl from the wet glue moisture. I have a lot of smaller pieces of exotic and hardwood veneers and it would take a life time of making slings to use them as small spacers between surface laminations, so I decided to try something new, skunkworks test #1: surface veneer lamination.
On top of the ply core, a layer of purple heart was laminated to both sides. This was left to try a bit before sanding down the surface.
In between the Paduak layers, I laser cut some maple veneer to contrast between the orange and purple. Again, left to set up a bit before sanding the face flat to receive the veneer.
This is the entire sandwich. On one side is a layer of cherry/zebrawood veneer and on the other side birch/wenge. Two scrap plywood boards kept everything tight and under pressure. I actually leave this for a whole day to ensure a good bond between the veneer and woods.
It’s a bit of a mess, but the careful planning and forethought will pay off in the end.
After curing, it was time to try skunkworks test 2: differential layer laser etching of the veneer. Using the laser set at a 20% higher power than usual, I try to vaporize the zebra wood to reveal the cherry underneath. Check!
Worked very well. I also want to note that I purposely used a more watery wood glue to bond the two veneers together to ensure that the layers are well set.
I do the same to the other side, but the Wenge is much harder than the Zebrawood, so there is only a different in texture and not colour. It is at this point I take the sling to the belt/disc sander and clean up the edges, revealing the sweet, sweet colour palette.
The spindle sander takes care of the rest of the burned edges and the insane amount of lay up work is showing it’s true “colours”.
This is where a bit of experience comes in handy. Having made many slingshots with plywood before, I knew that underlying layers would show up once the edge was routed. A rim of orange surrounds the dark hardwood veneers, making me very pleased with the progress. The top two layers of light wood plus darkwood makes for a very clean and graphic contrast.
Skunkworks test #1: scalloped grip areas. I have seen this done on many beautiful slingshots from other makers, but I couldn’t figure out how to do it correctly until now. I finally figured out that if I took the biggest drum on the spindle sander, I could use the top layer as a guide as to how much to remove and the general angle of contacting the drum. The existing curve helped guide the process along and the 100 grit drum took off material in a hurry. Before this step, I drilled out the tube holes and counter sunk them too.
After all the major machining steps, it was time to give the Turkey Shuckapow the full sanding treatment. 100, 240, 600 and steel wool, the off to the paint booth for three coats of acrylic. The clear coat really brings out that differential veneer etching, the cherry shining through the zebra wood.
The Wenge side is much more subtle, but the whole point is use this as a test bed for some previously unused techniques.
After some cure time in front of fan, I quickly wipe it with some steel wool to take off some of the glare. Then it’s time for a close up!
You are probably thinking…why did I name is the Turkey Shukapow? Because in the end, the colour, the shape, the lines, reminded me of a vintage 50’s bowling alley. What’s better than three strikes in a row? 10 dead centre shots with a custom slingshot.
Thanks for reading yet another long winded post…were you interested in HAVING it? Buy the Turkey Shuckapow here!
-Stay True-
-Eric
In this Metro Made post, I go through how I finished my first aluminum core slingshot: The Alugator.
Very recently a shipment of 6061 Aluminum 1/4″ Capuchin design came into the shop. These were specially designed to be stand alone slingshots after some finishing or other scale materials could be laminated on it. Aluminum is such a beautiful material finish and use, so I thought, why hide it all?
I started with a nice, freshly planed slab of Cocobolo wood, one of my favourite slingshot woods. Naturally oily and very hard, Cocobolo also as a dark, tight, swirly grain that is unlike anything. After designing and laying it out in Illustrator, I sent the job to the laser cutter, which faithfully cut out the shape.
Mating metal with wood for the first time. The holes are undersized to .1″ so that I can drill it out to .125″ for the stabilizing pins.
6061 is a nice crisp alloy, strong, but yields to HSS drill bits. The undersized holes on the water jet cut parts make for easy registration of the drill bit.
Applying some double sided tape to the scales so that they can be temporarily attached to the frame.
At this point, I am very excited….
A 1.5″, 100 grit sanding drum takes care of about 90% of the sanding, making the scale flush with the frame.
Once the edges of the frame were sanded, the scales were removed and the remaining edges inaccesible while mounted on the frame, were sanded flat. This removed the laser cutting burned edge.
All of the edges were sanded with a 240 grit sanding drum for an even, smooth face.
I went back to the laser cutter and cut out a 1/4″ Baltic birch plywood scale shape and mounted the scales on it with tape. This is necessary as the 1/4″ router bit needs a guide to ride on. At this point, I name the slingshot, the Alugator! The shape of the scale reminded me of a gator head.
A quick pass on the router rounds all the edges.
I forgot to take a pic of the plywood but one of the edges of the tips was sanded just a bit to reveal a gap to push a pry tool into it. This helped separate the layers after I pressed them together to adhere the tape.
I turned my attention back to the frame. One pair of pin holes would be exposed so I used a tiny 1/4″ counter sink to make the hole look nicer, and a 1/4″ counter sink broke the edge of the tube hole.
Beginning to look like a sweet piece!
The grip is also very comfortable to hold.
Using a marker, I trace the rough location of the scale position so I can chamfer the edges of the frame in the correct places. If I didn’t do this, I could accidentally ruin the smooth seam between the scale and the frame.
After knocking off the edges, I use a 1/8″ rail tail file to cut in the flat band attachment grooves.
I speed things up here only to be slowed down by the drying time of epoxy. Some heavy 40 grit sand paper roughened the mating surface.
Before epoxy, I finalize the shape of the scales.
I couldn’t take any pics of the gluing process, since it required gloves and quick timing. I fed the copper tube and the mosaic pin into the frame before applying epoxy, then sandwiched the scales on. Pressure, provide by the clamps, squeezed out any excess epoxy. I used a few cotton swabs to mop up any excess epoxy that oozed out at the areas that I wouldn’t be able to get at with the spindle sander.
After an hour, the epoxy was hard enough to work on.
A couple of light passes on the belt sander erased the epoxy on the surface, revealing the mosaic pin and copper tubing.
Using the pins as registration, the Metro Grade skull and the name, Alugator was laser etched into the surface.
The remaining epoxy was sanded off with the spindle sander and the exposed edges were quickly run over on the router.
After sanding the scales with 100, 240, 600 and then some 000 steel wool, it was time for three coats of acrylic sealer.
That’s it! Then it was off to the photoshop.
Expect many more aluminum core slings from us, we have a lot of them and we have a lot of cool wood and scale materials coming to the shop.
Thanks for reading!
-Stay True-
Eric
When I was commissioned by Prairie Fire magazine to make a few slingshots for their annual fundraiser, I gladly accepted the challenge. This Metro Made documents the creation of the first of the two, the Flatland Flame.
I started with a familiar design, the Harlequin Capuchin. Laser cut some 1/16″ thick purple heart slabs. Since the piece of purple heart I had was only 3″ wide, I had to split it up in halves.
To get a bit more contrast between the purple heart and laminated faces, some maple veneer was also cut.
Slowly, but surely, each piece of the puzzle was cut from various woods. Shown here is some Cocobolo, some Padauk and some Tulipwood.
On the back side is Rock Maple and Padauk. To complete the main face, Chakte-Kok, Bloodwood, Yellow Heart and a maple circle.
Now, the longest and hardest part of the build, the lay up. To start, the Purple Heart halves are glued to the plywood frame with some maple spacers.
After about 15 minutes of compression, the veneer is sanded flat, ready to accept the next step.
The maple veneer spacer to complete the layer. This was repeated on the other side to mirror the wood pattern.
Like the original Harlequin Capuchin, I started with the simpler back side because it take less time to setup and dry. Zebrawood and Wenge spacers make a nice texture between the contrasting woods.
Finally laying up the last pieces of the back side, spaced by Ebony and more maple. Slightly less than 30 minutes later, the face was sanded flat and it was onto the main face.
It’s messy, but it’s the way it has to be….
Another 30 minutes later, the face was ready to be flushed. Before more sanding, I moved back to the laser cutter to etch in some markings.
The Metro Made Skullthulu getting etched into the maple circle.
Flipping it over, the name of the sling etched.
Cleaning up the edges from the laser cut burning and refining the shape a bit.
To relieve some pressure on the final round over, all the edges where taken down with a 1/8″ bit.
Like the Mesquito Supernatural, select edges are taken down with the 1/4″ bit.
Sanding…lots of it. 100 grit nail file, 150 grit foam block, 240 foam block, 600 grit paper and a buffing with 000 steel wool. It’s the smoothest I’ve ever gotten wood to be.
2 coats of acrylic sealer and I washed my hands of this project.
The incredibly smooth surface thanks to the steel wool provided a perfect substrate for the sealer, the photos don’t lie.
Yet another satisfying job done.
-Stay True-
Eric
Working with uniformly planed wood is often very nice, however the surprise of a natural fork is always welcome. True hand carved natural tree-fork slingshot are timeless, but they just don’t excite me as much. When a friend sent me a huge mesquite wood fork, I knew exactly what to do with it.
I have been wondering if this technique would work but as soon as a new, huge bandsaw with a dedicated carbide tipped re-saw blade showed up at the shop…it was time to get going on this. I started by sanding a little bit of a flat spot on the high spot of the fork, this could be used to ride on the fence for splitting.
After the first slice, I got REALLY excited. I’ve never worked with mesquite before so this was a complete surprise.
Things got even more interesting as the second slice came off.
4 slices later, a fork became a leaning tower of wood.
For this run of slings, the three middle slices are useable. There is still one more smaller slice for another project.
Pre-laser cut Baltic birch cores show up and mark their territory, the scale is perfect. The pattern gets penciled on, ready for band sawing.
Rough cutting on the band saw, trying to save as much of the mesquite as possible.
…and the chips that couldn’t be used, saved for a BBQ dinner!
The grain that is destined for the face looks interesting. The side that is going to be glued to the core/laminations is sanded flat. This was no small feat as mesquite is incredibly hard but the smell made my mouth water (it’s been a VERY long winter and spring/BBQ season is here!)
Another new thing that showed up is some micarta spacer material. At 1/32″ thick, a sharp pair of scissors was able to cut through it.
To give this Mesquito some more small detail, some mahogany and maple veneer was laminated together to create a spacer between the micarta and the mesquite wood.
The whole sandwiched was placed under as many clamps as I could get on it. I don’t want it to come apart.
After some time, the excess was cut off and a closer rough cut was made. A Forsner bit was used to open up the pinky hole.
Then it was time to move over to the belt sander, cleaning up the faces.
..and sanding down the outside curves and edges.
A fresh 80 grit sleeve makes short work of the laser cut edges and flushes up the whole package.
There was enough to make three slings, the third one on the right is for the friend who gift the fork. I love these photos since they say so much about the process of preparing and laminating.
Since this wood isn’t something I have a lot of, I wanted to take careful steps to round the edges. To do this, the entire sling got passed over a with a smaller 1/8″ round over bit. This will reduce the material being removed by the final 1/4″ pass.
Selected edges are rounded off with the 1/4″, the finger and thumb area, the waist and pink hole. The tips are also rounded for the rubber tube to roll over easier. It now safe to proceed to chamfer the holes and open up the tube slot.
Now for the fun part. Laser etching! On the mesquite, the Metro Grade Skullthulu and the name Mesquito.
On the cherry side, the series name: Supernatural (Edit, fellow sling maker Nathan over at Simpleshot let me know he’s already using Supernatural, from here on in, we are going to call it the Unnatural Series)
Time to sand and sand and sand. The progression is 100 nail file, 150 grit foam block, 240 grit foam block and finally 600 grit paper.
First of three coats of acrylic sealer.
The sealer reveals so much in the wood that I can’t help but take a pic after the first coat.
The grain on this mesquite is something else!
After the first coat is cured, the surface gets a light scuffing with some 0000 steel wool.
The final coat. As per usual, the entire surface gets a treatment of a nice nail buffer shine.
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Here we are! The Metro Grade Mesquito Unnatural! Banded up with a hand cut, green double suede pouch and a short length of 2040 tubing for some wicked speeds and light draw pull.
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If you have a large fork and want to donate it to the Metro Made project, contact us and we’ll make it happen!
Thanks for reading! Now go make something!
-Stay True-
Eric
If you haven’t gone and liked our Facebook page, you should. Why..? Because we are holding a big contest, with a chance to win one of our prized Metro Grade Harlequin Capuchin FB’s!
All you have to do is like the top post about the contest, share the link and then in the comments, guess how many parts it took to make it!
The draw will take place on May 1st, 2014, so get your ballots in!
Having been an avid collector of mid-century modern furniture and a huge admirer of the Eame’s design manufacturing sensibility, I wanted to see if I could take the lessons I’ve learned from one of Industrial Design’s masters and apply it to something else besides famous chairs.
I am never one to compare myself direclty to the Eames’, but I do like to think I am a constant experimenter like they are. This time around, I wanted to take a slight three-dimensional approach to slingshot design, I speak, of course, the recurve slingshot. The recurve slingshot is a slightly more ergonomically design, made to fit the more canted, naturally forefinger/thumb forward position. The frame is usually bent into a curve, where the middle, ring and pink fingers can more easily grip on to them.
In this instalment of Metro Made, I attempt to make a recurve slingshot. Many successful recurve slingshot designs involve carving and removing material to create the curved portion, but very few, if not at all, use a bent plywood frame.
I start with 5 layers of 1/8″ Baltic birch plywood. On the top layer of this soon-to-be sandwich I laser etch a pattern of the handle in which I wanted to be bent. These layers where, one by one, laminated together and then compressed onto a pine form. In hindsight, I should of cut the layers longer so that they would have more room to bend, I don’t like wasting material so I did what I could. This was clamped down for 45 minutes while the glue set up.
After removing the now curved formed from the buck, I used the band saw to cut off the excess material, and use a medium size drum with 80 grit on the spindle sander to refine the shape.
After achieving the desired shape, I turned my attention to the pinky hole. The majority of the material was removed with a 7/8″ spade bit. The final shaping was done with the spindle sander.
You can see the handle take shape.
Before gluing the two hemi-spheres together, the edges were knocked down with a 1/8″ round over bit on the router.
Since it would be impossible to blend the Baltic birch together to hide the seam, it would a great chance to make a feature out of it. 4 stacked veneers made for a nice detail.
After clamping to ensure the joint is as strong as possible, the excess veneer was sanded off and the mismatched routered edges were bended together with some heavy grit sandpaper.
To further strengthen the joint, 3 nails were driven into the yoke.
When placed on a flat surface, the full effect of the bent plywood combined with the vectored glue joint can be seen.
Applying 3 coats of polyurethane, after each coat a rub down with some steel wool, the final result is a smooth slingshot with great grip. Since there is a potential danger of the forks separating, the heaviest band set I would place on this slingshot is Theraband Black.
Thanks for reading yet another build post,
The next time I decide to make this again, I am going to do things a bit differently, but for a proof of concept, this recurve slingshot is some thing I can have a lot fun explaining how I made it.
-Stay True-
-Eric
Sometimes, a nice long, complicated project is all you need to really get over your creative slump. Carefully calculating how things go together, taking the time to properly do clamp things down and lovingly polishing your new creation, it’s all in the details.
The Dark Horse is exactly that.
After doing some tests, all the dark woods that I had selected for this project absorbed too much heat to be cut so the result was a very burnt and singed edge and surface. So, switching to manual navigation!
I could at least start with a couple of cores and and a back side scale. This time around, a 1/4″ slab of purple heart, a 1/4″ slab of American Walnut and a back side scale of Black Walnut. The walnut laser cuts and etches nicely so the name Dark Horse and the MGG skull was etched on it prior to assembly.
After the cores where cut, it was time to lay up the bits of wood. Tackling this like a Tetris game, sanding slowly to fit the blocks into place, delineating the layers with a triple stacking of contrasting veneers (maple, ebony, maple). The inside core is American Walnut, which is much lighter than the Black Walnut used for the backside.
Always choose a hard wood for the fork tips in case of a fork hit, in this case, Zircote. It has a VERY interesting micro texture and is hard as nails. Sandwiched in the middle and will eventually make the scoop of the yoke, is Zebrawood. Below that is the aforementioned triple stacked veneer. In the center is rectangle of Wenge (this was purposeful), the Wenge is flanked by Black Palm end grain and some more of the American Walnut.
After gluing up the final bits, Black Palm and Pau Ferro for the pinky hole, the excess was cut off with the band saw. The whole face was then flush sanded to reveal the nice geometric dark wood pattern.
Once that was done, it was time to trim up the new hardwood face so that it conformed to the shape of the rest of the body. Using a 1/4″ flush router bit, the final trim was quick and easy because I built the pattern on a laser cut blank. I’ll make note here that going at a steady pace is more important than speeding through the pass on the router, hardwoods chip really easily.
After laminating the cores to the new trimmed face, the hole for the tubes needed to be drilled. 3/4″ of existing hole as guide made locating the holes pretty easy.
Moving over to the spindle sander to clean up the laser marks on the sides of the Purple Heart, American Walnut and Black Walnut cores. The Zircote is already showing its amazing stepped grain.
Switching bits to a 1/4″ round over, select edges were taken down, mainly the parts where the hand hits. The Black Palm is now showing its very unique, vascular bundle texture. The Pau Ferro (on the pinky hole) is also showing it’s wide, dark streaky grain. The other edges were knocked down with a 1/8″ round over bit but no photos were taken of that process.
I wrote before that the Wenge was placed in the heart of the face for a reason. Wenge is exceptionally hard but it also has a differential density between the grains. This means each vein of wood will react differently to laser etching, aka heat. Knowing and understanding this material property, I scaled a knight chess piece vector to be etched into the Wenge. The etching gave a pleasing wavy texture to the graphic and the outcome was as expected, a textural difference between the wood’s sanded surface and the etching. This would be further enhanced when the polish is applied.
Despite taking precautions and a steady hand, there was still some chipping that occurred at the wood’s mating joints. Some ghetto wood filler, glue and saw dust, filled those gaps easily and blended back into the wood work.
I took extra care in sanding and prepping the surface to accept the acrylic spray, going from 100 git foam blocks, to 240 grit nail files to 600 grit paper all the way to 1000 grit strips. Then it was off to paint, 4 coats of spray with a light buffing in between to smooth out the overspray marks. If you look closely, you can see the laser etching detail is much more clear once the clear coat hit it, the ridges of the etch, surrounded by the smooth surface.
45 minutes later, the coating is now ready for a polish using my super secret sauce, the nail buffer. A 4 step foam block backed with progressive grits, close to 10,000 grit in roughness rating.
A couple of minutes of buffing and its off to the photoshop!
Thanks for reading!
Had enough? Want to buy this slingshot? Get it here: Dark Horse Capuchin Slingshot
-Eric
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It’s been far too long and it’s time for another Metro Made post, this time around, something familiar to you returning Metro Made readers. If you are tuning in for the first time, welcome! Metro Made is the blog of Metro Grade Goods and how I turn raw materials in the stuff you see on the site. It is my way of letting you know where things come from and how they are made. Besides, who doesn’t love a good behind the scenes.
In this installment of Metro Made, we take a look at how I took the plunge and crafted 8 super laminated slingshots in one weekend. A pretty daunting task since a single unit took 5 hours to complete. If you are at all familiar to scaling up production, you don’t just take your unit’s build time and multiply it by the number of units you are making. There are always ways to save time. Despite the time savings, this oct-build still took 15 hours to complete. This one is a long one so take a potty break if you need to now, those of you joining me DURING a potty break, I commend your multitasking mindset.
The Harlequin pattern is something I developed when I made another Metro Made project, the Art Deco Loris. It was my ploy to use up a lot of small, left over wood ‘sprues’ generated when laser cutting full frames from planks of hardwood. The results where a stunning selection of hardwoods arranged in a very pleasing Art Deco style.
There were a lot request to have this available but the Loris was not the most popular slingshot to begin with, so I decided to go with a more universally appealing frame, the Metro Grade Capuchin. A smaller frame with a lot of potential for slicing and dicing for the Harlequin pattern, I went ahead and did that. I started by laser cutting the 1/4″ Baltic Birch plywood cores. I planned to make 4 Harlequin Capuchin TS’s (Tube Shooter) and 4 Harlequin Capuchin FB’s (Flat Band).
The biggest difference between making one of these versus eight is parts management. With 8 sets of near identical micro bits of wood (close to a 30 some odd part count per slingshot) something to keep them in order was necessary. Here’s what I used:
Adjusting the laser so it would only shoot out 50% of it’s 75 watt beam and speeding up to a max velocity, I made a template to organize the parts as they came off the laser cutter. The material is a scrap piece of hardboard. The next few photos show how the parts started to fill up the puzzle grid. I chose to go with rock maple for the fork tips since it is one of the hardest woods that can be laser cut and it is also readily available.
Not long after, the Honduran Mahogany, Black Walnut, Paduak and some more maple was laser cut and placed in their respective spots. You can see how the puzzle board is necessary now, and this is just one side.
The final pieces for that side were cut from maple, here’s the video to prove it.
Here are some shots of the backside puzzle board. That’s some Walnut and a piece of vintage Oak reclaimed from an ‘old’ friend (who is young at heart!). Meet Mervin, the most brilliant guy I know.
Once all the parts were cut out, it was time for the hardest and longest part of the build process; the lay up. I wanted to start positive so I began with the back side. With less parts, I would feel like I was accomplishing more and carry me through to the more complicated side. The forks get glued on first, since they are the only parts that need critical alignment, especially on the flat band version. The tips were clamped for 10 mins to ensure a good bond.
Here the Oak goes on but with a Zebra Wood spacer to fill in the laser beam kerf, this only fills the gap, but lens a little bit more pizzaz and detail.
The final bottom pieces were added (solid Birch) and left to set up a bit. Once they were more solid, the whole thing was flush faced on the belt sander. This is one of my favourite states of a slingshot build, revealing a built up pattern is pretty great.
Now, the painful but rewarding part, gluing up the 30 some odd parts that make up the pretty face side. I didn’t take to many photos of this process but as you can see, this part required a lot of attention to detail. The detail I particular enjoy is the red heart wood (Chakte-Kok) I used for the Metro Grade skullthulu logo. Even though I know that the red will deepen in colour once it hits UV rays (natural properties of the wood), the dramatic red splice in between the slabs of Walnut are really something else.
You’ll notice the face sanded frame has the Metro Grade skull sanded clean off, this was a mistake on my part since the Chakte-Kok wood was thicker thank some of the wood so the etching came clean off. No worries, I had a plan to return the etching back on the face the Capuchin.
After many, many cycles of this gluing, sanding, fitting and more sanding, the result was a respectable stack of work, worth of calling it a good day’s work.
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*One night later*
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The next morning, it was time to get cracking, knowing the project would have some finality to it. First order of business, flush sand the sides of the Capuchins and remove the burned laser cut edge. Thanks to a fresh 80 grit spindle sanding drum, this was a mere 30 min job for all of them.
This next photo represents 10 hours of time, kind of crazy to think. I call it ‘Fist full of Awesome’.
Remember when I said I had a plan to return the Metro Grade skull back onto the Chatke-Kok wood circle? This is that plan. I knew I wanted to mark on it that this was a limited edition of 4 (4 TS’s and 4 FB’s) so I again used a scrap piece of wood and quickly etched the outline of the slingshot so I could realign the already assembled and glued slingshot back onto the laser bed. This technique is also what I used to realign and re-etch the skull on those slings that had the face sanded off.
Now the most dangerous part of any slingshot build, the router. Things can go VERY badly here and the entire sling could go to waste if there are any slip ups. Thankfully, I’ve had lots of practice with this model having made a limited edition of 10 plywood ones and various other hardwood versions. Despite my comfort level with this pattern and frame, I treat every time I turn on a switch to a machine a chance to die. It works, seriously.
This photo doesn’t show anything new, but I wanted to grab a pic of the router shavings. Such beautiful array of colours.
The Capuchin TS and the Capuchin FB both have things that still need to be done with them before the band attachment area are operational. The TS’s tube slot needed to be widened but not before the edges of the hole are chamfered with a 1/4″ counter sink.
Then it’s off the band saw with a fairly narrow, 1/2″ blade, the tube slot gets widened to a saw width. The existing tube slot was not really a tube slot at all, it was merely a guide for the alignment when gluing up the layers and subsequently, a guide for the band saw to slide into.
Then the notched ‘iron sight’ needed to be cleaned up too, so a round rat tail file comes to the rescue. Under the TS is one of sanding blocks used to sand the surfaces of the sling. These are 80/120 grit mini blocks meant for manicurists, but for those tight curves and hard woods, they are perfect.
I didn’t take any photos of the FB slot finishing as it’s a bit of a secret but essentially it just needed to be sanded out to improve the consistency in the width of the slot for Theraband Gold and pure Latex bands. Once they were all sanded with 600 grit paper, it was off the paint booth to shoot 3 coats of acrylic sealing spray.
Once they were cured (acrylic spray only has a 30 min cure time), they were buffed to a shine with another manicurist tool; the nail buffer. It was time to hit the photoshop.
BUT before you go ahead to the final product and images, I want to list the woods used in these slings:
– Baltic Birch plywood core
– Rock Maple
– American Black Walnut
– Honduran Mahogany
– Chatke-Kok
– Maple Veneer
– Ebony Veneer
– Zebrawood Veer
– Birch
– Paduak
– Oak
…ok enough stalling.
I am pleased to present the Harlequin Capuchin TS and FB.
Thank you for reading to the end, it’s not often I get to spend this much time writing about my process and methods, but I know it’s always worth looking back on projects like these.
I am also really happy (but with begrudgingly) to announcing that Metro Grade is now on Twitter, you can follow and reach me at @MetroGradeGoods
3 of each Harlequin TS and FB will be available at the Metro Grade Shop.
Find the Harlequin Capuchin FB here
Find the Harlequin Capuchin TS here
-Stay True-
-Eric
Since February 2006, the humble blog Strobist fashioned by seasoned media photographer David Hobby, has spawned an army of photographers wielding small off camera strobes, producing stunning and technically challenging imagery.
By using light weight equipment, smart thinking, public discourse, open-source education, and creative and often unconventional light modification sources, the Strobist movement has taught 1000’s of amateurs how to light and convinced professionals that sometimes a 1000Ws studio strobe is the only answer.
The backbone of the Strobist methodology of photography lighting is using ultra lightweight and compact lighting support. While this is the goal of MOST photographers, Strobist or not, David hobby introduced one of the best kept secrets in the photography support catalog, the Manfrotto Nano 5001B (formerly 00B). I am not saying I discovered this secret before, but I also used one of these in my 15 years of professional photography, however mine was a very early model with friction locks and a non-black finished. This baby has been with me literally everywhere, through most of Asia, western Europe (include it’s birthplace, Italy), a whole bunch of the Mid-Western and East Coast of the USA and across Canada. This maybe not be the 5001B with it’s new school cool, but it sure didn’t give up at any moment. I’ve since retired it in favour of the 5001B Nano because I did like the anodized black finish.
The Nano 5001B is one of the lightest and smallest flash stands on the market with plenty of Chinese variations, and David made a great post about how to hack it into something super portable, quick to deploy and easy to carry. This post is about how I pimped my newer 5001B, which has been around the block already but I recently updated it with a few new video features.
1. Leg/Umbrella Management, elastic cord
Let’s start with the simple, this mod is so simple and so cheap that it is a no brainer. The cost of this mod is maybe, $2 if you go fancy, free if you have some of this stuff lying around the house. One of the few pains the Nano stand has is the legs tend to be a bit floppy when they are closed up. This is due to the geometry of how they fold up, backwards to any other conventional light stand. It accounts for it’s mere 18″ closed length. David uses a ball bungee for this, which does the same thing, but I found that I lost more ball bungees without some kind of retention system. So I came up with this adaptation.
To manage this is simple, you need:
1. A length of shock cord (can be from a ball bungee)
2. A cord lock that can fit the shock cord through
3. A cord end.
The result is this:
Pretty simple right? This can taken off and used like ball bungee to tie up strobes or hang up stuff but only when you need it, otherwise, it’ll stay put on the Nano stand. This gets looped onto the tightening handle of the legs, the cord lock is used to cinch up the shock cord and the cord lock on the end is a nice way to finish it off as well as give yourself something to pull on.
In addition to wrangle the legs, the shock cord is also used to hold a full size umbrella onto the closed stand, making this a nice tight package with no movement on parts.
This is how it looks when the shock cord is looped all the way around the stand and then hooked back onto the handle.
2. Shoulder Strap
This is one of those mods that when I saw it, I hit myself in the forehead. Of course, why try and find a bag for something that I will just use as one unit when I can just carry the whole unit as is. David drilled 2 holes into one of the legs and threaded on two keychain splitrings, which gave him two mounting points for a strap to be clipped on. I liked the idea of it but I didn’t like how much noise it made (the clanking).
I used some 1″ D-rings and 1″ gaff tape to attach them to the leg that nests into the split of the upper leg collar. I did this for a few reasons, the split of the leg mounting collar kept the leg from shifting side to side (kind of important if the all the weight is carried on that leg) also the position of the collar and the tightening knobs meant that the only place to store the umbrella was the opposite side of the closed nano stand.
Think I am crazy to think of such a minute detail? When you have 10 minutes to set up, take a photo of the president of a company and breakdown again, it pays to know where things go and have it go smoothly.
The shoulder strap is from some random bag that I don’t use anymore, so it was a perfect choice.
Here’s a closer look of the D-Rings and how it was wrapped on. The tape is fresh since the old tape was looking a little haggered. Bright tape helps others see the black stand on the ground and also if I needed take the strap off if the ground is wet, I don’t need to fumble around in dark situations to find the D-rings.
3. Monopod Foot Mod
Alright, here’s where my version of the Nano stand system differs from any other. I am finding myself doing more and more video, much to my chagrin and wielding a nearly 6-8 lb camera and keeping it steady is a feat best left to higher beings. While attending a wedding in Hong Kong, I noticed one of the crew documenting the wedding using a curious little monopod foot that looked really good. I asked and he showed me where I could get one. A day later, I had in my hands a Benro ST1 hydraulic universal monopod foot. I had already thought of how I could incorporate this into a Nano stand, knowing the bottom base bracket was solid cast aluminum. I bought the one with the 3/8 thread to get the maximum amount of support.
The Benro ST1 is a mini tripod foot, meaning it has three legs. The Nano stand also has three legs, so I thought I would be able mount the ST1 on the bottom and have the short legs nest in the empty space between the Nano legs. I was right!
I drilled and tapped the bottom of the Nano stand with a 3/8″ thread, ready to accept the ST1. Not going to lie, I misfired and didn’t hit the centre of the base, but it didn’t effect the result much.
After mounting the ST1 on the bottom, the effect is as expected. The legs of the ST1 nest PERFECTLY into the legs of the Nano.
When open, they lock into position and the integrated ball head allows for a smooth freedom of movement on nearly any terrain.
Since legs nest, it will not affect the Nano’s leg extension, even when lowered into its tallest position.
One of the added advantages of having a second set of smaller legs is that if the bolts are tightened for the ballhead on the ST1, it will stand up on its own. Making this a perfect stand for those places where you can’t deploy the full legs need a super low profile (untouched, indoors) naked flash stand.
Which brings us to our final mod, the business end, the flash bracket.
4. Universal Monopod/Flash Bracket Mod
Only wanting to carry a single implement of support, for video work and the very occasional low light situation where I need I monopod, I needed to make sure the flash bracket end was modular. I’ve been using the Arca-Swiss style tripod mounting system ever since I saw Kirk Enterprises and Really Right Stuff and their amazing camera L-brackets which allow for the camera to be mounted in the vertical position without tipping the camera over on its side on a tripod, super unique and useful. As such, the system is a little pricey, but have been adopted by many manufactures reduced the initial cost of moving to that style of mount.
I started with looking for a compact flash/umbrella bracket, having used dozens of kinds, the Manfrotto one is the best. Unfortunately, the Manfrotto umbrella bracket comes with a huge flaw: its size; it’s huge. Way over scaled and overkill for the smaller flash units that I use. Many eBay searches later, I found one that not only appropriately scaled, the tilting mechanism for the flash/umbrella is index with 5 degree movements, making it impossible for it to slip down or up, its locked in and sturdy.
From there I applied a quick release Arca-Swiss tripod mount on top where the flash would go and a matching plate, I screw in a cold shoe for a flash to sit. More times than not, this is its home state. The flash or PocketWizard TT5 will mount on this, an umbrella is slid into the mounting hole we are off to the races.
When I need to use the monopod features of stand, I simple remove the plate with the cold shoe…
Slide the camera into the Arca-Swiss mount…
Close up the Nano legs, open up the ST1 legs…
Adjust the height for my standing height (shown here at its lowest position), and we are ready to shoot!
The only major mod that I’ve shown here is the drilling and tapping of the 3/8″ thread in the bottom of the Nano stand, the rest is just careful and considered applications of readily available parts. I hope this was informative and will inspire you to reduce the amount of time spent on setting up equipment and start shooting more!
I can’t wait to get this thing dirty!
-Stay True-
-Eric
Been a little while since I’ve posted a build log, a LOT of working going out the door. So, this is an older mod but one worth posting, it is a modification of one of my favourite budget knives, the hotly debated Sanrenmu 710. Sanrenmu is a knife and tool manufacturer based in China and is one of the largest contracted OEM producers for such companies as Spyderco, CRKT and some other larger companies.
As such, they are tooled up to produce their own knives and tools.
This is an experiment to mimic the use and ergonomic situations of a knife I don’t currently own, mostly because it is fairly expensive and it’s discontinued, The Spyderco Jester. A stout knife, the Jester is based off the keychain line of knives and uses the same frame as the Spyderco Lady bug, but has a much more useful shape and ergonomics. The forward sloping blade, finishing off into a semi Wharncliff style blunt edge can be used like a scalpel with a series of small jimping grips for an index finger. This is feature is found exclusively on the Jester and no other knife (that I’ve come across).
Since I liked the ergonomics of the Jester, I wanted to see if it transferred well to a larger knife. The SRN 710 is a near perfect match for a scaled up version of the Jester.
Here we go.
First…mark where the steel will be removed. I went with a generous curve to follow the blunter sweep of the forward blade edge, and then shape projects straight back into the spine.
Using a 80 grit 1×30 belt sander (the radius portion of it) the spine is slowly ground away with lots of water dunking breaks to keep the knife cool.
When the final shape is achieved, I switch the belts to a 320 grit to get a nice surface finish.
This part I forgot to take a mid way pic, but basically I use a Sharpie marker as marking fluid and space out evenly a row of 1/16″ scalpel grip jimping.
Once I was satisfied with the forward grip, I moved on to the business end of the knife, the serrations. I took a standard pattern approach to this, using a 2-1-2-1-2 pattern. Marking it again a with sharpie and spacing this small serrations at 1/8 and the large ones at 1/4″.
Here’s the fun part, carving the scallops. The small rounds I used a 1/8 rough diamond bit, sinking in only about 2/5 of the way. If you do them all at once, you can adjust the depth of the as needed, getting these even is crucial for the angle grinding.
The large scallops I used the small stone bit and went in the same depth as the small scallops.
Now….the hardest part of the game…grinding the edge of the serration. If you’ve done your prep work, did some ghost movements with your hands you can really easily repeat the same motion, I have done this a lot and I can get a pretty good natural 20 degree grind. I found painting the scallops first with sharpie helps show how much material and shape of the grind to aid in matching them up.
The small edges I used a fine grit diamond 1/4″ bit, moving it up and down as it contacts the steel to get a nice uniform finish. With 6 of them, it’s tough to match them all up.
For the larger serrations I used a 5/8″ fine grit diamond bit, again moving up and down as I grind away.
The result is a nice even row of neatly placed serrations that look factory (after some burr removal via a piece of wet 600 sand paper). I buffed out the scratches and buffed the surface of the new serrations with a very hard cone buffing wheel I chucked up on my lathe.
Finally, using my Tri-Sceps sharpener, give the SE a crazy sharp edge.
Testing out the scalpel grip….nice.
And the saber grip…classic
That’s how I did it, for a $7 knife, it was worth trying it out, if I failed…it would of only been a small price to pay.
Here are some more shots of the modding knife next to a factory fresh one.
One big added bonus is that the blade is now a tad bit lighter, which makes deploying the already really fast deploying edge even faster!
A closer look at the scalpel grip jimping, they cleaned up very nicely after a quick buff on the hard cotton wheel.
Another look at the final blade, I feel that it’s enhanced the look of the blade why still maintaining the lines of the original knife.
The DIY serrations are only chisel ground which isn’t the BEST option for edge retention, but it makes for easy touch ups and sharpening.
Thanks for reading and hope you can invest some time and try it out for yourself, no tools in this Metro Made post were out of reach, so all it takes it some time and patience.
Stay True.
-Eric
Been having a lot fun with the whole idea of compression tube/band attachment. In this post, we’ll go through a quick iteration and evolution of the mechanism. While the set screws are great for attaching bands, it still requires an Allen key. This new build method achieves a tool less adjustment.
The Grivet slingshot is named after the Grivet monkey, found in Ethoipa, Sudan and surrounding areas. They are noted for having tufts of hair protruding alongside their faces. When designing the the shape of the Grivet slingshot, the ‘tufts’ of hair were pulled from the forks, which double as finger and thumb grip areas.
The Metro Grade Loris uses a recessed threaded insert (1/4-20) and set screws for the attachment. The new Grivet slingshot is a simplified version of this. Instead of using aluminum, stainless steel hex nuts are captured into place via some strategic laser cutting and layer of materials. In this photo, you can see the 2nd layer (the first being a backing layer). The 2nd layer contains the slots for the bands/tubes to slide into. The are about 1″ deep.
The 3rd layer, is where some precision cut hexagonal shaped holes where laser cut to accept the 1/4-20 stainless hex nuts. These nuts are a little less than 1/4″ thick, which is perfect for the a thickness of 1/4″ Baltic birch.
The final top layer is where the branding and face sits, this also where the nuts get captured by centred holes which will also accept the pricey black anodized thumb screws.
The holes are larger enough for the shoulder of the threads to sit in, but the head remains out. The one BIGGEST advantage of using thumbscrews (besides the tool less function) is that you cannot over tighten the band set, risking delaminating the outer backing layer.
Once it was all glued up, all the same procedures on finishing a slingshot were done. To see exactly what is done, check out the Metro Made Loris post. Three coats of acrylic spray and some light buffing, this Grivet prototype is done!
Currently, it is banded up with 8mm Linatex bands attached to a Metro Grade Heifer GP pouch. A couple slices of the same suede cowhide was used to buffer the screw and the Linatex, preserving its integrity.
This post doesn’t stop here. You may have noticed in the feature image a walnut version of this….you weren’t mistaken. After confirming that the mechanism worked, it was off to the laser cutter once more to cut up a set of parts for a walnut Grivet.
Probably doesn’t much explaining, but the only difference is the fork tip shape. About 3mm is added to the outside edge to clean up the profile and add a bit more strength to the tips themselves.
Time to get shooting!
Stay True
-Eric
Wanted to make a quick post about our new compression tube attachment method found on some of our slingshots, The Loris PFS and The Pygmy Marmoset. A short video of how it works and some images of tube detached.
Ding Dong. The Purolator rings my doorbell, hands me a HUGE box and a tube, asks me to sign on the dotted line on the screen. Done. What is it? Why…an overnight shipment of Tellurium Copper from McMaster! To the lathe!
For the past week, I’ve been using the Delta Marker with great joy, but yet….I craved more. I had already made up a second, stubbier version of the Delta Marker, with better dimensioning and grip detail, in anticipation of some new materials arriving at the shop. This version didn’t stay in the shop for long as I sent it off to a friend who would I would rather have it, use it and cherish is than have it sit in my shop as a prototype. However, I managed to snap some pics of it before I mailed it out.
Here is the aluminum Delta Marker MKII. The middle section of the barrel is much shorter (about 3/8″) and the cap is longer (2″) so the overall length was reduced by 1/2″ but the function and balance was better.
The ribbing in the middle is something I am particularly proud of as they are evenly spaced and tidy, something pretty tough to do on a manual lathe with very little calibration. I later transfer this aesthetic/feature to the Copper version, which you can see here in this video, it’s 8.5 minutes long, so if you need to go to the bathroom, do it now.
As explained, the rubbing extends into the cap by 4 ribs and the whole thing weighs a lot…not sure how much but a lot.
Having only 12″ of this pricey alloy, I could only afford to screw each part only once. I took a LOT of time making sure things were lined up and the spacing on the ribbing was perfect. I am super happy with this design, I can’t wait to get the brass and acrylic rod in.
Thanks for reading!
-Eric
Sometimes you just gotta. Made from over 60 individual parts, the Art Deco Loris follows the visual lines and definition of colour of the art in the 1930’s and 40’s. Made from a variety of exotic and local hardwoods, the Art Deco Loris PFS was a labor of love.
Crafted from Rock Maple, Honduran Mahogany, American Walnut, Rosewood, Purple Heart, Paduak with Oak/Mahogany/Walnut/Birch Veneer spacers sandwiching a multilayerd Baltic birch plywood core, the Art Deco Loris PFS certainly was a complicated build.
This post is not really a build post but more of a showcase of both the final product and also the engineering behind the band attachments. To illustrate that much better, here’s a video on how it works:
Ok, so there was some build pics, c’mon, this was a lot of work!
As soon as the brass threaded inserts come in, I’ll make up some Lorises for sale!
Thanks for reading.
-Eric
The hotly debated PFS (Pickle Fork Shooter) is a slingshot made popular by Youtube user pfshooter, whose skills with ANY slingshot let alone the one he prefers (PFS) are legendary. Abandoning the traditional concept of gap in the forks for the ammo to pass through, the PFS is a minimalist style slingshot that is shot over the top and flip style.
There is little to no gap between the forks and with the right technique, practice (LOTS of practice, practice, practice) and patience can be even deadlier than most advanced slingshots. They are extremely popular because they are simple to make and usually very small, making it a very easy slingshot to carry in your pocket. The PFS style shooter has been used over and over again since it’s conception but the concept is always the same, a simple, narrow gap fork with bands tied to it.
The wrap and tuck method of band attachment produces a less than desirable aesthetic appeal. I desired a more clean approach, a more Metro Grade approach.
This is how we designed and made our version of pfshooter’s PFS, the Metro Grade Loris PFS. After rolling the idea in my brain bucket for some time, I finally decided to use a threaded insert and some set screws to pinch the band into the frame.
I started in Adobe Illustrator, building simple shapes and staying within the boundaries of the Original PFS dimensions (about 2″x4″). Also using some of my favourite scripts: Round-any-corner & Metaball (ARC)
Then it was off to the laser, which you can see here. One day, robots will rise up and rule the earth, but for now, they are happy to do our bidding.
The result is a nice set parts ready to be processed and glued up, the material is a 1/4″ Batlic birch plywood.
Before I glued anything together, I had to process the internal mechanisms. Like I had mentioned, I have been thinking about this for quite some time so it all came together pretty quickly and I had a lot of operations layed out in my head. The first operation was to roll the edge of the inside layer so that the bands would not be stressed out by a sharp corner. I had already marked where the edge needed to be taken down. A file and some sand paper made quick work of this.
The rest of the internal slots got a quick 320 grit sanding so it would be smooth, the laser cutter sinters the wood so its generally smooth but just to make sure. My original plan was to use a band set I made up with red 2050 tubing with a 5080 sleeve, but I later changed the sleeve to a 4070 since it was a bit tough to get the 5080 into the slot after it was assembled. Here’s how the tube set would sit into the fork tips, and a dry fit of the other parts.
All of the layers were carefully glued together, take care not to have excess glue squish into the tube slot. This was clamped for about 10 mins for the glue to set up.
Then the scallops were adorned with an inlay shim of oak (cut cross grain to make it bend easier).
Once it set up for another 10-15 minutes, most of the finishing steps aren’t that much different than any other MGG slingshot.
Flush sanding all the sides and faces (my favourite state of a slingshot)
Then router the edge to 1/4″ (except the top) and edge sanding with a 100/140 block:
Dry fitting the tubeset.
Dry fitting the aluminum 1/4-20 threaded inserts (I have brass ones on order, but for this prototype and proof of concept, these work great).
Then finally supergluing the inserts into their home.
Check for grip and admire the pre-finished state: check.
Check if the 3/8″ long, 1/4-20 set screws go in far enough…yup. The snot you see on the bottom fork is some glue and sawdust to fill in a chip that happen when cleaning out the hole with a drill bit.
Then throw some bands on it to see it actually works, it’s here you can see the 4070 tubing for the sleeve. Seasoned shooters will know why but for those reading about PFS’s for the first time, the sleeves do two things: 1. Protect the inner bands from receiving too much punishment when they retract back to their active state at the fork tip area and 2. They help protect the bands at the tube attachment area since they are bring compressed by a set screw.
Shoot 2 coats of acrylic spray on it, then sand with a nail buffer to get a nice flat finish. Then hit it again with ONE more final light coat. Then it’s off to the photoshop.
This was such a blast to make, and thanks to a LOT of forethought, no time wasted on a second prototype. The Loris PFS has so many layers of wood that it is getting a little past what the original intent of a PFS (extremely pocketable, thin shooter) but the clean band attachment and overall finish makes up for the beefy thickness.
Stay tuned for a more complicated, hardwoods version soon!
Thanks for reading!
-Eric
Back again with another instalment of Metro Made, this time dressing up our newest slingshot, the Sifaka BB, transforming it into the Hardwoods Sifaka BB. You wouldn’t believe how much work it was!
When we laser cut our hardwoods for slingshots and products, we try and save the left over sprues (not true sprues but the best word to describe it) so that we can use the unused wood for smaller projects such as this. Since the laser is so precise and digitally controlled, we are able to carve out small chunks of premium woods to make interesting patterns and features.
The Hardwoods Sifaka BB shooter starts out with a 1/4″ baltic birch plywood core. If we stacked three of these together and finished them, it would become a regular production Sifaka BB. As you can see, our plan was to make a few of them, which generated a nightmarish pile of very tiny bits of wood that we had to sort.
After a quick sort and dry fit, the Maple, Rosewood and Walnut pieces were slowly glued onto the plywood core, staring with the fork tips. By aligning the fork tips first, any accretion of error could be sanded out, but as long as the holes for the bands remained true, the rest could be fitted accordingly.
We learned from making the Carcharo Rotary cutter that the kerf of the laser leaves a gap between parts, which allowed us to insert some real wood veneer. In this case, some red zebra wood and oak, giving a nice deliberate transition between dark and light woods, and a clean separation between the dark woods. We couldn’t take any pics of the gluing process since it involved 3 hands but it looked a little like this:
After clamping and allowing the glue to set up a bit, all of the faces were sanded flush using a variety of power sanding tools. A large belt sander for the front and back faces, a disc sander for the convex surfaces and a spindle sander for the concave ones. There is something about that semi finished state that we love the look of.
Looking back at the gluing process, everything else can can be approximated and adjusted, the only part that needs registering is the band holes. After flushing the surfaces, it was onto the router table to give the entire slingshot a 1/4″ radius.
After sanding the slingshot with a bunch of foam blocks with various grits, we hit it with a couple of coats of acrylic spray. We could use polyurethane but acrylic is faster to dry and has a shorter off gassing period. We can also use our most favorite tool, the nail buffer, to buff the coating to a nice smoooooooooth surface.
Those more seasoned slingshot shooter maybe wondering why this design doesn’t have quick change slots. Firstly, the design is much more simple without the slots and there isn’t enough meat on the fork tips to accommodate a slot. Secondly, these particular latex tubes last a LONG time, combined with a laser cut kangaroo ammo pouch, the need for quick change is not necessary. Thirdly, the modified matchstick method is reliable, safe and requires no special technique to shoot, unlike most looped tube slingshots. The red 2050 tubes that act as stoppers have two .177 BB’s inserted into each side so there is no chance it slipping back through the hole.
Time to go to the photoshop!
The final product, ain’t she a looker?!
Thanks for reading folks!
We hope these are interesting and engaging, we always found it appealing when we could find out how our everyday objects were made.
Want one?
In my day to day, I carry a pen and a Sharpie marker. I don’t remember when I started doing this but as soon as I wake up in the morning and get my day started at the shop, I always put those two things my my left pocket. I feel weird not having them and they really make up the core of my EDC items.
My most recent acquisition is the beautifully made titanium version of Jason Hui’s Alpha pen, which was a successfully funded Kickstarter project. Jason’s an insanely crafty guy, designing and manufacturing flashlights under his moniker, Darksucks. His low volume, high quality produces ooze style and class for the discerning gear guy/girl. His Alpha pen uses the finest of refills, the Mont Blanc felt tipped fine liner. At $4-5 each, the pen matches the pricey and beautifully writing capabilities of the refill.
Having a medium size collection of higher end custom pens, one of my greatest wishes was for someone to make a beautiful Sharpie marker holder. I’ve been waiting for someone on Kickstarter or other crowdfunding platform to make one, but no one seems to want to take up the challenge. Sharpie does make a stainless steel marker but the design leaves so much to desire and the refilled are fairly expensive given the relative short lifespan of a marker.
I finally broke down and spent some time in front of my lathe and made one. This is turned entirely from 5/8″, 6160 aluminum bar stock and using very commonly sized imperial HSS drill bits. The clip is from a Sanrenmu knife that seats itself into a flat spot milled into the face of the cap.
Basically, it’s a sleeve that accepts the grip, tip and ink well sponge of a regular sized Sharpie fine tipped marker. Extracting this is pretty easy, just bend the plastic body of the maker till the body separates from the grip. Then slide it into the Delta body and press down with the plastic cap. This seats the “refill” fully into the new home.
I call it the Delta Marker.
Why Delta?
Well, it’s no match for The Alpha pen, and it’s not refined enough to be a Beta so, it’s the Delta marker. It is also based off of Jason’s design, using his cap posting design ad well as the capping design, so it’s only natural to follow his naming convention. The only thing missing is the shallow scallops on the body, to do this I would need a round insert holder, which I broke some time ago.
I also wanted it to seal, so I added a groove at the base of each 1/2 fine thread for an o-ring. This did two things, it won’t allow the nib from drying out, but it also engages the cap when torqued on a bit so it won’t accidentally come apart in my pants or shirt pocket. I actually came about this epiphany when the Alpha pen came apart in my pocket a few times, so I put a few, really small o-rings meant for a AAA flashlight seated at the base of each thread. Lucky for me, Jason designed a relief for the threads, which meant there was a groove for the o-rings to seat. Mine are much less precise, but they don’t need to be since the o-rings I used are much thicker to generate a better seal.
Just a quick note, these are not for sale, it was a personal challenge and this blog is a place for me to present final, in progress, experimental as well as failed projects. It’s not often something comes together so nicely on the first try, but thanks to Jason’s design, a lot of the guess work is done for me.
Here are some table top shots, under the Delta Marker is the Alpha pen.
Thanks for making it all the way to end of another long winded, designer rage fuelled build. I am really happy with the Delta Marker and it will serve me well until I can get this design in CAD and possible CNC this.
-Eric
I know don’t know who thought of this first but it was pretty neat. I recently bought a couple of these figure 8’s with the idea that I could do the same, but I just couldn’t bring myself to just wrap flat bands on it. I finally got to making my own figure 8 slinger, this is how.
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Most often, aluminum climbing descender figure 8 slingshots are made simply by cutting the larger ring in half and then wrapping some flat bands on the top. I don’t really like OTT (Over The Top) slingshots and still much prefer TTF (Through The Fork), I also have been getting back into tube shooting for ease of use and the quiet release sound.
The figure 8 descenders are used in climbing and repelling as a means to slow down the rope via friction. They have since been retiree to just controlling gear and less humans but they are still used in climbing. They are mostly made from aluminum with some steel varieties. They are sized perfectly for the hand and as recent history has prooven, they make great slingshots.
Here’s how I made mine.
Lets start with cutting the larger ring, not quite in half but close. A metal chop saw makes short work of this step.
The edges are ragged and uneven, so a disc sander and a belt sander trues up the ends. These will become the fork tips. At this point, some would stop here after some rounding of the tips, band some Theraband to it and call it day.
Having never seen a version of this kind of slingshot that can shoot rubber tubes, I decided to venture down that road. I scribed the centres of the tips and drill the holes out to 7/32″ and finish with a chamber bit to knock down the edges of the hole. Rubber doesn’t like edges. My mill’s vice is only so big so when I want to clamp something larger, like this slingshot, I use two quick clamps to apply even pressure on the object with in the vice.
A couple of quick process images and few test shots with a set of bands. Not quite done yet…
The smooth anodized aluminum is quite slippery so the next steps address this as well some aesthetic concerns. Body of the slingshot is masked with tape so the vice would not mar the finish. Then the tips of the forks are sanded with a nail file to remove the anodizing.
After the rough sanding was done, a Scotcb-brite drum wheel was used to knock down all the scuffs. It’s at this step that I decide that this slingshot will be name the 505 Yoke, as it’s emblazoned on it.
Then some diamond compound polishing with a felt cone. Shiny!
After a painfully slow process, some black 5080 rubber tubing was slid onto the forks so that the aforementioned slipperiness is eliminated.
The 505 Yoke is essentially done, just needs some bands.
Awesome slingshot unlocked!
Of course, no slingshot project at Metro Grade Goods is complete without a trip to the Photoshop.
Then some actual Photoshopping.
The final results, the Metro Grade Goods 505-Yoke slingshot.
Thanks for reading another Metro Made post, it’s always fun to share and learn along the way.
I still have 2 more of these figure 8’s..maybe you’ll see one on the shop.
-Eric
Our sister company Skinth Solutions cut yards and yards of CORDURA nylon fabric everyday, it was time to join forces and develop a stylish and ergonomic rotary cutter we could both use. The only way to cut Theraband well is to use a rotary cutter, ones commonly used for textiles and paper. Theraband is the same high performance latex band used for resistance based exercises.
In this installment of Metro Made, we are going to show how we made the Carcharo (short for Carcharodon;Shark) rotary cutter.
Like always, we drafted the design up in Adobe Illustrator, using our favorite scripts, Metaball and Round-every-corner to make short work of building up shapes and forms. After that we prototyped in plywood to check for tolerances and fitting of the blade guard mechanism. Once we were sure of safety of the cutter (it is a razor sharp blade after all), we went ahead and laser cut up some premium woods.
We are going to skip ahead to that step, here are the parts all laser cut. The puzzle pieces are cut some 1/4″ American Walnut and the framework is cut from 1/8″ Baltic birch plywood. The walnut parts are sliced up in a way to create alternating grain patterns and more efficiently tile the parts on the stock. It is also a chance to inlay some contrasting maple veneer, since the laser cut has a 40 thousandths of an inch kerf, a single layer of wood veneer is a perfect filler.
Gluing up the parts is a little time consuming and hands on so we forgot to take some pics but here is a shot of another Carcharo glued up in the same manner. Note the veneer spacers/filler. The laser engraving is set to 25% more power than necessary so that when the 1mm of material is sanded off to flush the face, the engraving still remains crisp and intact.
Once the parts are all set up, the final lamination of the back side, inner core and front face was done. Edge and face sanding makes this project a little bit more clear.
Once everything is cleaned up, the holes were precision drilled out so that some 1/4″ brass tubing a 5/32″ brass rod could epoxied into place.With so much contact between the wood, these are mostly for aesthetics and detail. Normally pins and tubing are used to stabilize applied scales on a frame. With no other projects on the go, the wait time for epoxy to set up is unbearable.
Meanwhile, the blade guard needed attention. The thumb nubbin used to engage and disengage the guard could be just a rounded dowel, but that’s just not good enough. A laser cut 5/16″ disc was cut from the same walnut and glued onto the end of a maple dowel. The dowel was then chucked up into a drill and using sandpaper, the end cap was rounded into a nice domed switch. Again, this step was a little involved so the images here show a cocobolo end cap shaped the same way.
Turning the focus back to the main body after the epoxy set up, the faces were sanded flush and the all of the edges were rounded using a 1/4″ router bit.
Both the blade guard and the main body then went into paint, shot with 3 coats of fast dry acrylic coating.
A short wait later (mostly to let the coating off gas), a length of coyote brown 550 paracord was threaded through the spine for a nice palm cushion.
Tucking the end into the slot, the paracord is held in by friction.
Right now, we are using some hardware found on commercially available rotary cutters, hence the “pat. pend” sticker on the pivot. We have on order some 5/16, 304 stainless steel barrel bolts and 1/4-20 thumbscrews to complete the mechanism. That didn’t stop us from shooting some juicy product photos.
…and since you saw the cocobolo nubbin thumb switch, here’s a shot of the other Carcharo we made for a friend of ours, Barrow Built. This one is made from Walnut, Maple, Cocobolo, Rosewood, Baltic birch ply and Zebrawood spacers/fillers.
Phew, if you made it far, congratulations!
Thanks for hanging in there. It was fun documenting and writing this post. We hope to make a video for the Metro Made vlog about the Carcharo, made in plywood.
They will available Metro Grade Goods site soon!
When building custom slingshots, there three key areas of focus, the frame, the bands and the pouch. The last one often overlooked but it’s one of the most important parts of the slingshot.
We’d like to introduce the first Metro Grade Tuff Udder pouch: The Big Bertha.
Holding the ammo correctly, catapulting it forward, retaining its shape, these are all features of a good ammo pouch design.
Here’s a quick video of the pouches:
We started with a 1/8″ thick, heavily oiled cow hide and threw it under the laser cutter. The design features a ventilated body for increased speed and reduced weight. A middle hole centers the ammo perfectly for consistent results shot after shot.
The laser cutting left the surface dirty, marred with soot and residue. Since we wanted to wash these pouches with a light detergent to remove the surface oil, the bath also removed the grim.
We wanted to start out Tuff Udder series with the biggest and most versatile one, allowing the slinger to shoot anything from 1/4″ steel balls to big rocks found in the wild.
Just under 3″, the Big Bertha isn’t a small pouch, so it’s ideal for heavier band sets.
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We love dressing up production models and this one is dressed to the nines!
We took a Metro Grade Gibbon frame as a core, then laser cut alternating maple and purple heart slabs.
The laser cutter we use give us a perfect kerf line thick enough for us to insert some real wood veneer to fill in the gap. What’s more awesome zebra wood? Not much. Turning it on edge, the cross grain of the zebra wood makes for a great subtle detail.
After waiting for the glue to set (under compression), all the faces where sanded to reveal a flush surface, then select edges were rounded with a router. Coyote brown paracord completes the look and feel, acting as a thumb pad for those with larger hands.
