casting colours

[splinterinfinger]

Hi all I have been doing some research on casting my own polyester resin blanks, I spoke to company yesterday and they said I could make my own blank moulds by casting Viscolo Addition Cure Range RTV Silicone Rubber onto a pen blank and forming my own, my question is do I really need to do this or can I use a cheaper alternative. Then we got onto the subject of color pigments and he wants to know what is the name or make of the general colors that are used in making the blanks, only I think the one he sells is a paste any information on this would be great.

This is the UK website who I spoke to
http://www.tomps.com/shop/advanced_search_result.php?keywords=Addition+cure+rtv&x=10&y=11

http://www.tomps.com/shop/advanced_...id=0e434b160999c29a0a3350250a72f87f&x=16&y=10
www.tomps.co.uk

Many thanks Mervyn

 

[sbell111]

I cast PR blanks in one of four types of molds.

The first (and simplest) is a rubbermade-type sandwich-sized container that is sized just right for about five full-sized blanks.

The second is a Wal-Mart 2-piece ice ice cube mold that makes rods of PR that is a good size for a half-blank. I cut this mold in half so I can use it in my pressure vessel.

The third is made using 3/4 in PVC pipe cut to about 6 in lengths. I have a board on which I've recessed holes for these tubes to stand up in. I fill the holes with melted wax and stick the tubes into the wax (This stabilizes the tube and keeps the PR from sticking to the wood.

The fourth is an RTV mold much like that is sold by Gadget. I had to make a mold to make this mold. For that mold, I used my table saw to cut up a white poly cutting board. I sized the original mold to create a RTV mold teh right size to sit inside my pressure vessel. Many people make block molds (like my first example) out of this material. Typically, they screw them together, but I duct taped mine. It worked like a charm. Once I have the box built, I glue four blanks into it using Goop, spacing them out evenly. I also 'caulked' the seams with Goop. Once the Goop had set up (but hadn't even fully dried), I mixed up a two pound can of RTV and pored it in. A day later I had a Gadget-like individual blank mold.

 

[Jarheaded]

There is a great tutorial on the home page about PR casting that tell you how to make a mold out of the bathroom sealer silicone(I think), it sounds good to me, but I have always been very happy with the molds made by Gadget. I may give it a try when the weather warms up and I can set them outside to air out.

 

[Mather323]

I have made the RTV molds and they work fine but Gadgets molds look much nicer and I don't have to wait for them to cure!!