Recently we received samples of ThermoCast's new RP-40 urethane. The kit consists of two bottles of "Side A" and "Side B" to be mixed together in a 1:1 ratio. The literature with it states that
". . . . .a new product for the prototyping and modeling industry . . . . Rp-40 is an unfilled system that requires no agitation, simply mix the two parts together and pour. It contains zero solvents making it virtually odorless and ideal for pouring against polystyrene foam. It has good impact resistance and machines excellently. . . ."
Here are some specs.
Product: RP-40 Mix: 1:1 by weight or volume Gel-time: 2.5 - 3 min Demold-time: 10-12 min Hardness: d-75 Heat-deflection: 300 f Shrinkage: .002 Viscosity: 200 cpds
Further correspondence with them about the product lead to the fact that they are currently working on new containers for the hobby market. the new containers will have a (exact dosage top) which means you can measure up to 25 ml by volume by simply squeezing the bottle.
As of yet we have not tried to cast anything using RP-40, however a full trial should be done in the near future and we shall report on the results then.