"Help!" for: Casting

[twistedxknights]

After sanding, I'm getting a lot of little pinhole pits, likely caused by tiny air bubbles in the liquid plastic. Is there some way to minimize this problem during the slush casting process, or should I just resign myself to trying to fix it with body filler later?

As for paint, the 321 seems to be taking paint just fine, as long as you use a coat of primer first.

only thing i could suggest is to use small batches when your slush casting instead of one larger batch

[Chantelle]

SK: Some products release vapours in heat and humidity that cause that, and other times it can be caused by dust in the mould. Not sure what would have caused yours, though!

[Destructo Pup]

To help eliminate the tiny air bubbles your resin really should be degassed before the pour. If it is a fast cast resin that you wouldn't have time to degas before it kicks off, you can degas both parts (A & B) seperately then 'gently' mix them together with a stir stick before pouring into your mold. A couple other ways to help eliminate air bubbles in your casted parts... especially if you don't have a degassing station... is to be careful 'how' you pour your resin into the mold. A careful pour that doesn't allow a lot of bubbles to foam up will help eliminate bubbles in your casted part.

Another trick I use a lot was to dust the inside of the silicone mold with baby powder and then bang out all the excess so your left with a nice even LIGHT dusting. It helps the resin flow throughout the mold and helps eliminate air bubbles especially in detail areas.

[ventrue]

A couple other ways to help eliminate air bubbles in your casted parts...

I have also seen additives that are supposed to have that effect. They were simply called "degassing agent" (rough translation), so I'm afraid have no idea what they actually consist of, but they might be worth looking into.

[cory045]

thanks for this it really helps

[spartan-b312]

is really useful information

[saint ignatious]

oes anyone have a general shopping list for a guy who wants to start the moulding process? im not new to the concept (pretty much how dentures are made and i been doing that for a while) so anything you would suggest i buy before i start up?

[009-SPA]

Has anyone on this site or otherwise casted with epoxy resin and Kevlar before? I'm going to do it the same way as with fibreglass, putting down a gelcoat first. Thanks in advance.

[sik1276]

Does Smoothcast require a respirator to work with?

Also, the only store around my area that sells Smooth Cast is way too far; the closest store is TAP Plastics and they sell something called Tap QuikCast. Does anyone know how this compares to SmoothCast, notably the 300/320 series?

[ventrue]

Does Smoothcast require a respirator to work with?

Some will say no, but I'd say yes, definitely wear one.