Prototyping Rubber Parts with RTV Silicone


I created a tutorial on how to prototype rubber parts with RTV Silicone, based on my experiences. Please check it out and share feedback. Thanks!

Awesome. Great little tutorial.

Picked up some new things too. Never heard of Nitto Tape. Gonna have to try it out.
Also writing the starting mold times on the foam core is a nice little trick I never thought off.

Thanks Emmanuel. Nitto, or “Permacel” (as it used to be called), was used a lot in my program for model making back when I was in school. I’m surprised you noticed the mold times. Good call- I’ll add that in the description.

Do you do a lot of RTV mold making?

I’ve done a bit. Although I usually use Smooth-On Products. Since they use the 1:1 Mix ratio and are very easily accessible.

That’s cool! I’d like to try Smooth-On in the future.

Thank you, great tutorial (I especially liked the pixelated highlighting technique).

I’ve done 3D printing to RTV model making slightly differently, 3D printing the mould and using the RTV silicone as the ‘rubber’ (easy to remove from slight undercuts, 1:1 mixture, 5 minute pot life):

The mould is SLS nylon from Shapeways, so better print quality (less stepping) than from a Makerbot etc. which you can see in the piece (it’s about 4cm/ 2 inches tall):

I tried shaking the bubbles out using an orbital sander:

but I found a long pour much better (any bubbles are stretched out and pop):

Really cool setup. I was thinking about the possibility of using a hard material for the mold as well, such as CNC or 3D printing as you demonstrated. It makes sense to do that with a high resolution print like you did with SLS.

nice, once my shop is set up ganna give this a try