Amount of Catalyst!!

[toolcrazy]

I do realize that the size of the cast determines the amount of catalyst. But, my question is how to determine how much you need to start. I'd hate to burn a $40 can of PR experimenting.

 

[mrplace]

I use 2-3 drops per oz for a 6 oz cast. I use 3/4 and 1" PVC as my molds and use the same amount for both molds.

 

[JimGo]

5 to 7 drops per ounce of PR is a good general rule to start with, assuming 1) you aren't in a hot climate, 2) you aren't casting in a pressure pot, and 3) you would like it to solidify some time in the following few hours to a day.

 

[its_virgil]

Have you seen these articles?
http://penmakersguild.com/articles/prinstructions.pdf
http://www.penmakersguild.com/articles/ribbonprocess.pdf
http://content.penturners.org/articles/2005/casting_polyester_resin.pdf
There are several more.
Do a good turn daily!
Don

Originally posted by toolcrazy
<br />I do realize that the size of the cast determines the amount of catalyst. But, my question is how to determine how much you need to start. I'd hate to burn a $40 can of PR experimenting.

 

[mrplace]

I have tried using 4-6 drops, but in Texas where it is hot and usually low humidity, my casts get brittle. Especially in 1" molds.