Introduction: 3D Printed Slingshot

About: Hi! We're the Maddox Brothers, Liam and Aidan. We collaborate so much together, we figured we'd consolidate our work onto one account. Liam is the industrial designer, and Aidan is the mechanical engineer.

This is a slingshot. Use it to violently defend your pillow fort or make a dent in the rabid squirrel population (of course we never condone violence, but when squirrels are involved, you gotta do what you gotta do. Okay but seriously dont shoot anything thats living or that you're gonna regret breaking). It is 3D printable for your convenience. The steps are as follows. Enjoy. -Maddox Brothers

Step 1: Design

If you have nothing better to do or want to imporve your ninja Fusion 360 skills, try building the model yourself. Start by sketching a full sized front view on paper. Use this for reference when you make the CAD drawings (or if your a wizard, skip this step and go straight to CAD). Once I recreated the sketch in Fusion360, I extruded it to the desired thickness. Then youll want to use the fillet tool to create the rounded edges. You may end up playing around with diffrent radiuses to get it just the way you want it.

SUPER HELPFUL TIPS FOR YOUR SLINGSHOT QUEST: Make a bit of a slot on the front and top of the slingshot where the tubes will go. This will help everything lay flat.

FOR YOU SUPER SNAZZY DESIGNERS: Add embossed text or designs by extruding into the face. Later you can bring out the contrast with some paint.

Step 2: Printing (Bringing It Back Into the Real World)

PRINT SETTINGS (if you care): Up that print infill to I'd say 20-25%. Thats a bit higher than average, but you really can't have this thing failing on you mid pillow fort siege. On a Series 1 Pro, we used 3D infill with a 5mm distance. It's held up in many a western duel (I was going to make a gunslinging pun, but *slingslinging does't make any sense).

Step 3: Sanding/Protective Coating

Every good slingslinger knows that their hands are their biggest assets. Keep that skin nice and smooth by sanding your print. Start with a high grit sand paper and move down. Once it's smoothed down you can optionally spray paint it or polyurethane it (yes weird, but it totally works). We used spray polyurethane to give it a nice finish.

BONUS TIPS: If you printed with ABS, you can smooth the print with acetone. Google it. It's dope.

Step 4: Creating the Pouch

If you've already taken down one of those squirrels you're one step ahead. Go ahead and take that leather salvaged and draw out a pouch shape on the back. Use an exacto knife, or your sharper incisor tooth to cut out the design. Don't forget to use a ruler on the straight lines. Finish up rounding the edges with sandpaper. If the leather is too stiff you can just sand the outside to thin it up.

TIPS FOR HOLE PUNCHING: If you don't have a leather punch, a sharp punch awl should work. If not, get working with that exacto knife.

Step 5: Bands

We can't use plain old rubber bands for a tool of this caliber. Get yourself a spear gun rubber band. Some sporting goods stores will carry this, if not, try ordering on line. Try looking for "latex rubber tubing".

TEST #1: I tried it with two one foot bands and they work but may be a tad long for your taste so modify to suite your very specific needs.

Step 6: Attaching the Bands to the Pouch

Here we test your skills. I'll keep it simple (no jokes, sorry) (this is the trickiest part, if anyone needs help, comment and I'll clarify in the comments and in the post!)

1. Cut a hole about 3/8" from the end of each tube on only one side. This hole needs to be big enough to fit the tube back into itself. PRO TIP: insert a screwdriver into the tube to prevent it from deforming while you cut.

2.Intert the end of the tube through one of the outer holes in the pouch. The hole in the tube should be facing outward.

3.Take the tube and feed it back through the hole you cut in it. This should cinch down the tube onto itself. The tube might want to stick to itself, so I suggest you use some dish soap and water to slick it up. You might need to insert a pair of needle nose pliers into the hole to hole it open.

Step 7: Connecting the Bands to the Slingshot

This step shouldn't be too difficult. All you're going to need for this is 2 thicker rubber bands I actually ended up using RC Airplane rubber bands for attaching the wings on foam rc planes. With one hand you'll have to hold one of the tubes on the front of the slingshot. With the same hand also hold a pair of needle nose pliers on the other side of the slingshot fork. Take one of the ruberbands and wrap it tightly around the tube as well as the pliers as many times as you can while still leaving a small amount of the band to tuck. Now slightly open the pliers and close them down onto the excess band and pull it under all of the wrapped band. This should hold the rubber band and your tube tightly to the slingshot.

-Set main tube on front of slingshot and needlnose pliers on pack.

-Cut a thick normal rubber band

-wrap that rubber band tightly around the tube and the pliers

-once you have wrapped several times around the tube, slingshot and pliers pull the rubberband under the wraps using the needlenose pliers

Step 8: Shoot It!

You're ready to give your slingshot a test! Find somewhere you're not going to break a window or hurt someone and have some fun.

Those squirrels aren't going to wait, and your pillow fort requires defense. Take up arms and fire away.. but,


Step 9: Disclaimer/Warning


I take no responsibility damage caused by your slingshot or injury sustained by it. Please do not use to shoot at any other persons (or animals ok, be nice) .


Slingshots are dangerous and they can hurt you!

Make sure to check your tubes every once in a while to make sure they aren't slipping.

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