New forum for me and have enjoyed the reading of some interesting posts. over the last few days.
Not so new to resin castings as I have been in the casting game for 25 years and 18 of those are with resin, mostly white metal spin casting, but half of my full time work is now resin casting. Model Trains, Car parts, etc
Have only worked on the pressure casting side of things 3 years and would like to know 2 things
Is there is a good resin for this casting method. I have bought a slow set resin but who has 3 hrs to wait for each run of a particular mould. Most of the resins i have used are from barns, easy cast, 4PU , super Cast all very good for most things. the problem with slow set( Barns TC 891) is the aggressive nature of this resin I found destroying the mould in only 7 or 10 castings.Not after the usuall 30 or more. The Moulds are in the Barns 4601 pink, a good rubber after all the other rubbers I have used. Castings I did were Ok and no holes but the 3 hrs of the resin in the moulds just killed the mould .
2 With the slow set resin placed into a pressure chamber, what would be the approx time it takes for the process of the air bubbles to be eliminated from the casting . I have tried the 4PU resin in the pressure chamber on the expectation that the removal, or should that be depursal of air bubbles throughout the casting maybe a rapid action. Quick enough to be complete before the resin sets. On my experiments it indicates I am wrong . The dispercial of air is a slow process. Unlike the vacuume procedure .So if any resin is used with a set time of 15 min or less the pressure pot tec is not going to work .
any surggestions would be appreciated.
Thanks Johncast
http://www.orncastings.com