My very own slingshot design.

After the rather short taste of success with the rambone slingshot, I decided to design my own. I used the T-splines plugin for Rhino to freeform model the body.

I call it the ‘BIG GAME’ because it looks like a deer from the back. And because it is so badass you can use it to hunt. 🙂

Here’s a short clip showing off the CAD file:

The middle part is supposed to be aluminium. But I got impatient (alu stock was in the mail) and did a quick test out of plywood. I still did it in 3 parts though: the two shells and a 3mm plywood core.

And the result, together with the Rambone:

It turned out beautifully, but obviously was not strong enough to handle a lot of force. Usually wooden slingshots are pretty sturdy and therefor rather bulky. My design features more elegant lines so I really needed the aluminium core for strength. If you look at the side profile, you can see how thin the fork really is.

When my aluminium finally came in, I epoxied the two remaining shells (I made 2 extra in the video above) to the aluminium core and boy did that do the trick! This thing is scary when drawn full-length. Here are some comparison shots of the real-life object next to the original design:

Sadly, I made a dumb mistake with the CAD file. I still have the file, but I can’t modify it anymore using T-splines. Because I sliced the model in three parts, it sort of consolidated the meshes and they cannot be edited the way I did before slicing. I thought I saved an unsliced copy of the file, but apparently I was wrong… Luckily there’s no monumental flaw in the design so I’ll just use it as it is.

The next thing to do is make another piece out of more beautiful hardwoods. The plywood lines are cool, but overall it looks dull and honestly had too many faults and gaps inside the ply. I used more woodfiller than I would have liked to make it somewhat smooth. I have a whole stash of exotic woods waiting to be machined. But I have something special in mind and the hardwood is rather expensive so I am going to have to do some tests first to get it right the first time.