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I have a lot of interest in simple, mechanical, things. Something that requires an energy source and that does not involve electricity or fossil fuels is always super cool to me. Water wheel fed saw mills, steam powered work shops, bicycles, yo-yos, fully manual lathes, a hand saw, and the list goes on.

This is what brings me onto my next project which is a slingshot. Now I have to mention that I am not a hunter and I typically have no desire to kill anything except the occasional mosquito. I really know very little about slingshots and I suspect there is an entire world surrounding these simple devices that I know nothing about. I just happen to think that the simplicity of a slingshot is pretty cool and the transfer of energy that it is designed to deal with is intriguing.

I have had an idea in my head for a very specific style slingshot for quite some time now. The design is fairly detailed and it will take some dedicated AutoCAD time to come up with a workable design. I had never built a slingshot so I thought that a practice run might serve me well and that way I will have a better idea of how to build my final design.

So over the last couple of weeks I milled away aluminium and spun it down to my desired sizes to finally come up with a practice version of a gordsgarage slingshot. I did not start with any specific design in my head. I built it as I went along and it turned into what it is simply by chance. The morphed design worked out well in the end and I am pleased to say the slingshot is actually functional. I have had multiple test firings with it and it appears to work as designed.

So as per usual the entire process is documented in picture format located below. There is one video included in case you are interested. I also included a picture gallery closer to the end. I had too many pictures to post so I condensed a bunch of the final shots into an album.

 

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The project started off by obtaining a slingshot band and some ammo. I have plenty of loose ball bearings kicking around but I figured I would go genuine.

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Onto the fabrication process. Like I said…I didn’t have a plan in place so this is how it all started. I knew that I wanted finger holes so I made the slingshot to specifically fit my hand.

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I measured the OC (on center) point of my fingers on my left hand as well as the diameter of my middle knuckles then I started to drill some holes in some 6061 aluminum.

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With the holes milled to fit my fingers I started to shave of extra aluminum.

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The final step in the finger holder was to mill a tab tab that would eventually slide into the handle assembly. Here one corner of the tab was cut, just needed to finish off the left side.

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I didn’t have a clear vision for the “yoke” of the slingshot but I had a general idea. Since I didn’t have any round aluminum stock large enough I decided to machine something out of .375 aluminum flat bar. I started with a 4″ x 4″ section and mounted it to a lathe arbor.

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I included this picture because it shows the 4″ diameter I am shooting for. 5 minutes on the lathe will bring it from 4 corners to pi.

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Getting closer to my final dimension. Makes me wonder if there is a mathematical term for a square with rounded corners.

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So with my 4″ circle compete I set things up on the milling machine to hog out a center, offset, hole with a hole saw.

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Back onto the lathe I switched out the 3 jaw chuck for the four jaw and dialed in the center hole. With a boring bar I cleaned up the previously cut hole to dimension.

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Now I am back onto the milling machine where I needed to position the part precisely in the chuck as the next step involves drilling symmetrical holes.

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I had a plan in my head that was BrainstormCAD’d at around 2:30 am on a sleepless night. It involved drilling a stepped hole in order to secure the slingshot band this way making the install look super clean. It is rather difficult to put into words so I will just mention that the design actually worked.

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Here is my progress so far. I post the picture to help illustrate the order in which things are done.

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As you can see from the previous picture the handle is nothing more then a 1.250″ chunk of aluminum stock. It is time to start working it over. I need to fit the finger holder into the handle. Instead of milling a slot out I figured I would remove a bunch of the excess material with a drill bit first. I don’t think people appreciate the cutting power of a drill bit enough. Perhaps now would be a good time to reflect on their abilities.

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With the holes drilled I then dropped in a .375″ end mill and hogged out the remaining material.

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Here I am able to test fit the finger holder and it just happens to slide in perfectly. Amazing what can happen when you use math.

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I needed to secure the finger holder to the handle so I set it up in the mill then drilled, and tapped, 5mm holes to accept stainless steel allen head bolts.

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I needed to flush mount the non-yoke into the handle. Since the handle had a .375″ slot machines to accept the non-yoke I need to mill off a flat section in order to close up the visual gap that would have been evident with a radius.

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I have some ideas in store for the base of the handle. As I plan to build multiple options I decided to drill, and tap, a 6mm hole into the bottom.

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The handle was looking rather plane being just round and smooth. I thought I would give it some grip by dropping in a .375″ ball nose endmill 60 degrees apart around the circumference.

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The ball nose machining gives the handle both a functional, and visually pleasing, aspect.

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With the 3 main components completed it was time to enter into finishing stage. I had contemplated anodizing certain components but in the end I thought that a brushed look suited the project. The finger holder was cleaned up using a die grinder and sanding wheel.

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Here are the 3 main components cleaned up with a brushed finish.

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With the main slingshot machined it was time to start on the handle bases. Like I mentioned earlier I installed a 6mm thread into the base of the handle in order to accommodate different bases. I had many ideas to build however I decided to limit myself to just three. Here is the start of the first base. It is a chunk of 2.50″ round aluminum that will eventually be turned into a 9 round ammunition holder.

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Onto the milling machine where 10 holes where drilled, 9 of which will accommodate the 3/8″ ammunition.

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Since I am planing to hold the ammunition in place with 1/8″ rare earth magnets I cross drilled the previously machined holes so that I could epoxy the magnets in place.

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With all the crucial angles machined I cleaned up the visuals on the lathe.

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Here I sat down at the sunny kitchen and epoxied all the 1/8″ rare earth magnets into place.

The video posted below shows the loading of the slingshot ammunition into the holder. The ammo can be loaded from either side and the magnets are plenty strong enough to keep them in place.

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The second interchangeable base would be nothing more the an over sized hook attachment to allow for a caribiner to hook onto. Started off with 1.250″ aluminum stock and trimmed the sides flat.

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Dropped a 5/8″ endmill through the middle to make room for a caribiner to clip onto.

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Moved onto the lathe to clean up all the visual lines. Gave it s tapered finish.

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Rough machining completed of the caribiner end.

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As another option for a base I decided to adapt a triple blade carbon arrow head onto the end. At first I was going to pass on this idea as the arrow heads are rather sharp but when I discovered I could buy protective pods to prevent any unwanted injury I figured I would go for it.

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This is the first, and second, stage machining of the arrow head adapter. The center hole was drilled and tapped to accept the threaded arrow head. The outer three holes were machined only for cosmetics.

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The arrow head adapter was tapered down on the lathe to give it a more stealth look.

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All the components of the slingshot received a brushed finish. The finishing touch was the glass bead blasted gordsgarage “GG” gear logo. I created a .900 inch diameter logo on the vinyl plotter, applied it to the handle, taped up the rest of the surrounding areas and then shipped it to the glass bead blast cabinet for some etching.

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Here are all the machined, and finished, components that make up the slingshot prior to assembly.

The following gallery displays the finished product. If you click on a picture you will be able to cycle through all the remaining pictures at a decent resolution. The gallery shows multiple combinations of the ends. The ammunition holder can be used on it’s own or coupled with other options. Check out all the pictures to get all the details!

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Comments
  1. marq101 says:

    Damn, I envy your skill (-; Nevertheless, thanks for sharing!

  2. Edgar Rumbo says:

    ¡¡Magnifico Diseño, mucho Talento¡¡¡¡¡ Siempre estoy esperando tu proximo proyecto, soy aprendiz en el torno y con tus trabajos descubro cosas nuevas eres enormemente Bendecido por el Creador,
    Recibe un cálido abrazo fraternal desde Mèxico.

  3. The 10,000 quatloo question: How well does it work as a slingshot?

    • gordsgarage says:

      The answer to the 10,000 quatloo question is YES, the slingshot works fine. I feared that the ammo would hit the outer ring and not fire through the hole however aiming is not an issue and there is no risk in the ammo ricocheting. I am not a slingshot pro therefore I cannot give a knowledgeable review. It reached my expectations.

      Thanks!
      Gord

  4. […] Time was when a lad in need of a ranged weapon would hack a slingshot together out of a forked tree branch and a strip of inner tube. Slingshot design has progressed considerably since [Dennis the Menace]’s day, but few commercially available slingshots can match up to the beauty and functionality of this magnificently machined multipurpose handheld weapon system. […]

  5. Julien D says:

    Just found out about this site thanks to Hackaday. I’ve spent the last hour on your site and I really love your projects! Great skills and great ideals! Good job!

  6. yupsi says:

    Square with rounded corners is called a sqircle…https://en.m.wikipedia.org/wiki/Squircle

  7. Nice creation…would love to have a guiding & aimin facility on that…& release mechanism..:-)

  8. cody says:

    Damn fine work, as always. The ammo video is hypnotic. How long have you been machining?

    • gordsgarage says:

      Thanks Cody, glad you liked it. I picked the audio for the video for that very reason. I have been metal fabricating, as a hobby, for 20+ years. I actually only picked up the machining side of things over the last 5 years.

      Thanks!
      Gord

  9. […] goods store for around $10. If you’re western Canadian resident Gord, however, you instead machine something truly unique out of aluminum. As if that wasn’t enough, he also added an interchangeable base system to […]

  10. This web should be censored under the label of P0RN! OMG Such a nice job everywere I love when I discover a web like this and I can scroll down down down and still watching amazin new job.
    I just have look for you in youtube and I have seen that you have a channel but not update, you should check that because some videos have more than a million of views… You could get money making videos of your jobs… Yeppp and in instagram.

    Until then you have a new follower here.

    Congratulations for this.

    • gordsgarage says:

      Thanks for stopping by jaimemoradesign! I appreciate the enthusiasm and love sharing my projects with like minded individuals. Glad you have started to follow, I will try not to disappoint.

      Thanks!
      Gord

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