New Expanding Rubber! This our new Expanding Rubber for enlarging patterns. We have had much fun playing with this in our shop. You can find it here on our webstore: https://www.brickintheyard.com/collections/casting-rubber
Expanding Rubber is a Polyurethane formula that is mixed 1:1 by weight. It has a ~10 minute working time and may be demolded in ~8-10 hours. The finished rubber cast is then soaked in water to make it grow. Once the part has absorbed all the water it can, it will be about 150% larger than the original part.
Enlarged parts should be molded as soon as they are removed from water. As they dry out they will shrink back to their original size. Molds can be made of enlarged parts using PlatSil Gel-25 as we have done in this video. Parts may require several days to “grow”. The “growing” process will be proportional to the cross section of the original part. Thin parts will grow in a day whereas thicker parts may require over a week.
Post time: Jun-19-2017