How Long in Psi Pot

[vfauto]

Got my pot all set up and cannot find any info on how long to keep casting in the Pressure Pot. Please advise.

Thanks Frank

 

[Druid]

What are you casting with? is it PR or Alumilite?

If its PR then its really up to you and how much MEPK you used as a catalyst for how long you want to leave it in. You can demold using most most PR casting within 24 hrs. I usually cast and leave them in the pressure pot overnight.

If your casting with Alumilite then you can take the molds out of the pressure pot in about 20 mins.

Hope this helps

Jim

 

[seamus7227]

depends on what you are casting? PR vs. Alumilite? Tube-in casting vs. Solid color blanks? How many drop of MEKP per ounce did you use? What is the ambient temperature in the room where you are casting? When you ask a question like yours, you need to give more info so you get a more accurate answer.

 

[seamus7227]

Jim, great minds think alike!

 

[vfauto]

Thanks for replies

I will be casting with PR at about 68 degrees. They will be tube in and solid.As far as drops I will take suggestions.What other info do you need to give me accurate advice?

Frank

 

[Robertsmeets]

I am curious to see further replies, I was told at one point that I should not cast PR under 70.......
I typically use 4 or 5 drops per ounce of PR so that the blank does not become super brittle and u workable ........ but I am not a casting expert......

 

[Brooks803]

At less than 70 degrees casting PR I'd use 4-5 drops per 1oz of resin and leave under atleast 40psi for 8-12hrs. With PR different pigment types will cure at different speeds and the last thing you want is to release pressure too soon. So I'd take the cautious stance and leave it in there as long as possible.

You can always do a double cast and have 1 under pressure and 1 outside the pot. Use the same pigments, catalyst, etc. and time how long it takes for the outside pour to cure SOLID. That would atleast give you a baseline to go off of.

 

[JD Combs Sr]

At less than 70 degrees casting PR I'd use 4-5 drops per 1oz of resin and leave under atleast 40psi for 8-12hrs. With PR different pigment types will cure at different speeds and the last thing you want is to release pressure too soon. So I'd take the cautious stance and leave it in there as long as possible.

You can always do a double cast and have 1 under pressure and 1 outside the pot. Use the same pigments, catalyst, etc. and time how long it takes for the outside pour to cure SOLID. That would atleast give you a baseline to go off of.

I kind of do what Jonathon suggested. If I want the casting out of the pot the same day there is always a little resin left over in the pour container(3 or 5 oz paper cup in my case) so I will watch it and the stir stick I left in it. When the stir stick won't come out of the cup because the left over resin has hardened around it I figure what is in the pressure pot is done but if I am in no hurry I leave the pot under pressure overnight.

 

[Druid]

I will be casting with PR at about 68 degrees. They will be tube in and solid.As far as drops I will take suggestions.What other info do you need to give me accurate advice?

Frank

I usually refrain from casting under 70 degree's. If I do, then I take my pressure pots inside the house where the temp is consitant.