Mini-B Rear Tire Mold - Square Pin Tread

thingiverse

**Cast your own tires using this 3D printed mold.** The tires created by this mold are designed to fit a Mini-B rear wheel. **Resin Casting Tutorial Playlist** https://www.youtube.com/playlist?list=PLyysFycibsx2_bjo1-r2uoug9edZcFnTx **Related Prints** Printable Mini-B Rear wheel: https://www.thingiverse.com/thing:4965339 Resin Syringe: https://www.thingiverse.com/thing:5241082 Mini-B Tire Foam Insert Cutter: https://www.thingiverse.com/thing:5241546 **Required Hardware** M5x60 bolts x 4 (can be longer if you already have something that would work) M5 nuts x 4 M3 locknuts x 6 M3x8mm Screw x4 M3x20mm Screw x 2 (these can be longer if you already have something else sitting around) Danco #77 O-Ring x 2 (1-1/4 in. OD x 1-1/16 in. ID x 3/32 in. wall) Washer x 2 (0.897" OD x 0.375" ID x 0.075" thick) The O-Ring and Washer were found at my local Ace hardware store. I have included their dimensions incase you need to source them elsewhere. **Suggested Resins** I have had the best results using resins with longer pot life times. Something in the range of 15 to 30 minutes will give you plenty of time to mix, degas, and inject the resin before it starts to set. 40A urethane rubber has a feel fairly similar to outdoor soft tire compounds such as JConcepts green and Proline M3. I do not recommend 40A tires for running on carpet - they are too soft and the tread will be worn down in a matter of minutes. 60A urethane rubber has a much firmer feel and is a great choice if you plan to use the tires on carpet as it provides excellent tread life. I'd compare it to Schumacher's Yellow compound. Also, you will need a mold release. I have been using Stoner Urethane Mold Release E236. I have found one application is enough for multiple pulls. **Required Tools** Vacuum Pump and Vacuum Chamber Air Compressor and Pressure Pot Resin Syringe The vacuum pump is required to get air bubbles out of the resin after mixing it. The pressure pot is required to minimize/eliminate any air bubbles in the resin after it has been injected into the mold. The mold must be placed in the pot and pressurized until the resin has set. Finally, you will need a tool to force the resin into the mold such as a syringe. I have designed and printed my own syringe that I will also release on Thingiverse. My syringe requires 2x o-rings and a small portion of rubber tubing to complete.