RemingtOreo Automatic Hand Trap by ShrubTek

Last crawled date: 2 years, 10 months ago

Inspired by a recent episode of C&Rsenal's It's a Trap series (highly recommend if you haven't seen it yet), I give you the RemingtOreo Automatic Hand Trap. Following the same basic operating principles as the original Remington design but shrunken down, all of the parts can fit on an Ender 2 printbed at the same time (barely).
One thing to keep in mind if you want to yeet some Oreos, the channel is tall enough to fit most regular oreos but there will naturally be a few in the pack that are too thick. To be specific, the maximum height is 12.75mm. I also included a printable practice disc, so this can be used indoors without leaving oreo residue everywhere.
This design is comprised of 5 printed parts, and the following hardware:
4 x M5x10 bolt
1 x M5x15 bolt
1 x M5x20 bolt
1 x M5x40 bolt
2 x M5 washers
1 x M5 nut
1 x ~1.5" extension spring
1 x ~0.5" compression spring
Your local hardware store is the best bet for finding a good set of springs, I had pretty good luck at a nearby Ace hardware. Either way, it may take some trial and error, or shortening of springs, to get everything dialed in.
Build instructions:
3D print components: See the attached Cura screenshot for the recommended orientation. I used PETG with 4 walls and 30% infill (100% for the spring anchor), with support enabled.
Tap holes: Holes which need to be tapped for M5x0.80 threads are marked with red arrows in the same Cura screenshot. If you don't have a tap, you can just use a short bolt and a manual screwdriver. Resist the urge to use a power screwdriver or you may melt the surrounding area.
Assemble tension arm: Attach the tapered bushing (wider end on top) and the spring anchor to the tension arm using two M5x10 bolts. Make sure they can turn freely, but with minimal slop. Start threading the M5x40 bolt through the spring anchor, but leave about 4-5mm hanging out for now.
Assemble throwing arm: Line the 40mm bolt up with the guide slot, and use an M5x10 bolt to attach the tension arm through the hole closest to the guide slot. Once again, ensure the tension arm is tight but still able to move freely.
5: Attach tension spring: Slide the compression spring over the 40mm bolt, and then line the 5mm nut up with the end of the bolt. Hold the nut in place as you finish screwing the 40mm bolt into the anchor, compressing the spring in the process.
6: Attach throwing arm to handle: Pass the 20mm bolt through the handle and thread it into the center pivot of the throwing arm, placing a washer on either side of the handle surface.
7: Attach extension spring: Loop one end of extension spring over 10mm bolt, and and then screw said bolt into the bung on the handle. Insert another 10mm bolt through the other end of the spring, and then thread it into the offset hole on the throwing arm. Adjust throwing strength by shortening extension spring if needed.
8: PULL!
The set-up for the tension arm spring could use a little more refinement still, if you have a better idea of how to set it up I can send some STEPs your way. If you run into any other issues, feel free to let me know.