PR not curing.....need advice!

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wizical

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Jun 14, 2007
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Los Angeles, ca, USA.
I am fairly new to the casting world and having a total blast making blanks! but I have run into an issue that I hope someone can help me with.

what is the proper mixture of PR to Catalyst. what does everyone use to make sure their mixes cure properly?

can the sun help the curing process?

Thanks....any advice would be greatly appreciated

Cheers
 
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PSNCO

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3-5 drops per ounce. How long has it been since you poured the blank? Are you Using Silmar 41 or Castin' Craft? Put it in the sun on a warm day and it should help quite a bit.

Is it a colored blank? What did you use to color it?
 

Skie_M

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If I read the stuff in the forums right, it WILL cure without catalyst ... just that the catalyst helps it go a LOT faster. Without it, you will probably be waiting 3 - 4 months?

Warmer helps .... you could possibly set it in a toaster oven set at 150, but that could be asking for trouble... especially left on for extended periods.

Now .... left on top the fridge in your garage under a cardboard box with insulation around it (or a styrofoam cooler left upside down to keep the hot air in) .... that would be much safer.
 

PSNCO

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How many ounce pour?

Did you put in a lot of dye? Too much dye can mess with the curing process.

Do you remember putting in the MEKP? and how many drops per ounce?

It should be plenty warm enough in LA.
 

chartle

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Do you mean not hardening at all?

I've had blanks with too much dye in them take days to fully cure and then sometimes the ends were still feel tacky.

I've done 9 per oz but have cut back to 4 to 5 and my blanks have all cured.
 
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wizical

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I will try all of these tips.....maybe I used too much dye, that could be part of the problem

I have been using 7 drops per ounce

I am still experimenting with it all.....thanks
 

79spitfire

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Did you use alcohol based dyes? The alcohol can extend curing time substantially, to several days. Leave them sit and see what happens.
 

Philip E

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Can I add a question to this thread without hijacking it? if it is 80 degrees and 65% humidity what would be the recommended drops of catalyst per ounce? Which situation would cure faster, outside in the sun 80 degrees with a moderately high humidity or inside around 72 with a relatively low humidity?
 

jttheclockman

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Can I add a question to this thread without hijacking it? if it is 80 degrees and 65% humidity what would be the recommended drops of catalyst per ounce? Which situation would cure faster, outside in the sun 80 degrees with a moderately high humidity or inside around 72 with a relatively low humidity?
Sun will always heat faster. Humidity will not matter. The only time humidity can have an effect is if you are casting on a tube. Drops are realtive to many things. What is the resin??? Are you coloring and if so not all colors cure the same way. Types of colorant has an effect so not an easy question to answer. Experimenting will probably be the order. Can not go wrong with 5 drops/ounce to start.
 
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Sabaharr

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I cast in an average of 73° and in the humidity of south east Louisiana swamps just outside New Orleans. My castings are rock hard in 24 hours or less with 5 drops MEKP per ounce. I currently only use powdered dyes and sparingly at that, just enough that you can't see through the thin spots. I cast in various size PVC pipe, 1/2" for slimlines, 3/4" for larger pens, 1" for cholla blanks, and 1.5" for stoppers. Only problem I ever had was streaking purple with copper and forgetting to put in the MEKP. I dumped it all out and just mixed it together then streaked a little yellow thru it. Glad I remember the formula because it was smoking gorgeous. I would say that if you added everything like you were supposed to it will be OK in a few days at most. Patience Grasshopper (there I go showing my age again).
 

Cwalker935

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I think that Doulas and Sturgess may have a limited shelf life. I bought a gallon and had no issues for 3 or 4 months and then it just stopped curing. The half full can is still in my shop because I do not know how to dispose of it. I do not know if its the catalyst or the resin. I tried a different catalyst which did not work either. I have had other issues where the coloring agent that I was using was not compatible and the PR would not cure properly. Bouncy blanks do not drill or turn very well.
 

SantaEric

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buford ga.
Sun will always heat faster. Humidity will not matter. The only time humidity can have an effect is if you are casting on a tube. Drops are realtive to many things. What is the resin??? Are you coloring and if so not all colors cure the same way. Types of colorant has an effect so not an easy question to answer. Experimenting will probably be the order. Can not go wrong with 5 drops/ounce to start.
why would humidity be a factor when tube casting?
 
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