Sorry if this has been answered elsewhere (I tried searching!) but does anyone have any experience using 3D printed nylon as a mould for an RTV silicone part?

Specifically, my question is - would the nylon act as an inhibitor for addition cure RTV silicone (like this stuff)?  The specific type of nylon is PA2200, which looks like it's basically PA 12. 

I can't think of a reason why that nylon would cause problems, since it's not on the list of inhibitors, but I thought I'd check first!

Thanks in advance.

Dan

I can see no reason either why it would inhibit a cure.

However my understanding is the low grade 3D printers produce quite weak parts prone to splitting between printing layers so it is possible you might damage the original demoulding the cured silicone.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Thanks Warren - that's good to know!  It's a fairly simple part with no undercuts, so with luck it'll work... (fingers crossed).

Hi,
Here is a mould that I 3D printed in PLA for use with RTV silicone. I have had no problems with the strength. The cylindrical part that forms the hollow core has to be pulled out quite firmly after the silicone has set. The Silicone part is the end cap for an LED juggling staff.

Brian.

this is nice! like your way of working maybe sand the mould next time before use to get a nicer finish on the silicone part?

Matthieu Libeert
Founder MAT2 Composites X Sports
website: www.mat2composites.com

Actually, the printed finish of the mould gives an interesting texture/pattern to the finished product. I find that smooth silicone has a kind of dead flesh feeling.

The tabs at the side of the mould allow me to use a nut and bolt to pry the 2 sides of it apart.

Brian.

its a matter of preference, I understand what you mean good job!

Matthieu Libeert
Founder MAT2 Composites X Sports
website: www.mat2composites.com

These cheap 3d printers do seem to be revolutionising budget rapid prototyping.

I want a cheap 3d scanner and cheap way of CAD machining moulds from tooling boards.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant