Casting Resin 3D Prints

[Jagannath]

Hullo folks,

Quick q for those in the mould making know - I’m thinking of having my 6mm astronauts cast up. Does anyone know if I can produce the 3D masters myself or is ‘normal’ 3D printed resin not up to the vulcanisation process?

My googling is struggling because there’s also a whole genre of resin called ‘castable’ (to do with jewellery making that is throwing off the results.

Any help appreciated.

[Andrew Rae]

It does depend on the resin. If it’s the peachy coloured expensive prints, with proper support they’ll be fine in an organic rubber master mould but won’t survive being removed. The cavity will be fine though. In my experience the organic moulds have always given better results than silicone, which can stick to the print and tear the mould.

[beefcake]

If you don't go and do it yourself, Eddie at Zealot miniatures has a super high-end machine (8 microns if I remember rightly) but he would probably cost a fair bit and is knee deep in work with his own kickstarter. but 6mm astronauts might be not too costly I guess 

[Jagannath]

Thanks both - I did email zealot but I guess he’s super busy.

I suppose half of what I’m asking is what’s the problem moulding resin prints? A chemical thing?

[Mako]

I suspect you certainly can with the jewelry resins.

For the 3-D prints though, even with the fine detailing like from Shapeways, you'll need to seal the minis first, with some sort of clear coat. 

Not sure what is best for casting, but something hard and durable would be best.  Not sure if acrylic sealants are up to the job, but they may be.

I imagine a gloss coat enamel would be better though, if it doesn't destroy your printed plastic/nylon material.  Best to test it on a bit of sprue before applying to any figs just to be sure.

The printed minis will have numerous small pits in them, making them very rough.  I doubt you could get the mold material off of that easily, if at all, and even if you can, it will certainly limit the life of your molds.

I've read from one caster that says he never wants to deal with 3-D printed masters again, due to that issue. 

Even conventionally sculpted models need to be sealed prior to making molds from them, and sometimes the masters are destroyed in the process, so you should be aware of that too.

[Andrew Rae]

There’s no point moulding Shapeways prints for metal casting, the quality just isn’t good enough. Even if it looks passable in a matte material, it would look horrific in metal. Metal is not a kind material for print artefacts.

Either go for the best quality you can - nothing less than 15 micron resolution and 25 micro layers - or don’t bother with metal.

[Daeothar]

Are you referring to the results of those UV activated resin printers perhaps?

Because I have one from an Indigogo campaign; the Sparkmaker FHD, that's en-route (I'm tracking it on its journey from China to my house) as I type this. And for that printer, a heat resistant resin is offered as well. I was triggered by that fact, as it might be useful to possibly create moulds for metal pouring, or to print masters to create moulds from other materials.

I have not tried it obviously (I've been 'patiently' waiting for it to arrive since last November ), but I am curious about the results, especially since the resolution is supposed to be way higher than filament printers...

[6milPhil]

I suppose half of what I’m asking is what’s the problem moulding resin prints? A chemical thing?

It's the heat from the vulcanisation process of the mould making, it can turn milliput to dust, cook greenstuff to an often brittle brown, and if any glue is involved in the masters can bugger it up and you'll only know after it's done of course. There is a cold mould option though, but it adds a stage and therefore more cost, and from that you can get metal masters to make a vulcanised production mould.

Ask Pete of The Assault Group via https://www.facebook.com/themouldmaker/ he does all my casting and knows just about everything about the processes, is always delightfully honest about your prospects, does good work at great prices too.

[Jagannath]

Smashing - cheers Phil.

[6milPhil]

Happy to help mate. Have you got photo's of these? I'd love to see them.

Btw if Pete can't do anything for you just message me and I'll suggest someone else. 

[Jagannath]

Don't think I can embed Instagram pics, but here's a WIP:

https://www.instagram.com/p/Byd7oLOHXzU/?utm_source=ig_web_copy_link

I'll drop him a line and see where we get.

[6milPhil]

Thanks, excellent stuff.

[beefcake]

Those are nice!

[Jagannath]

Thanks dudes - need to get my batch finished!