Using Heat to Cure Resin?

joe966

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Feb 16,

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Livonia, Michigan

• Mar 27,

• #1

I have seen in several articles and videos that some people use heat to cure their poly resin quicker.

Most people say that they use silicone molds or bake ware, but I was wondering if I could use a small metal pan instead? Would the pan get to hot for the resin or will it work the same as silicone? Signed-In Members Don't See This Ad

Sylvanite

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Hillsborough, North Carolina, USA.

• Mar 27,

• #2

Polyester resin curing is an exothermic reaction - meaning that it produces heat. The hotter it gets, the faster it cures (and the more heat it produces, etc.). PR is really designed to cure at around 70 degrees Fahrenheit ambient temperature. Much hotter than that and you will experience increased shrinkage and a more brittle crystal.

I only heat my castings if I'm working in cold conditions (e.g. winter in an unheated shop), or as a post-cure to help eliminate the tacky surface.

I hope that helps,
Eric

joe966

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Feb 16,

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Livonia, Michigan

• Mar 27,

• #3

cold temps

the cold temperatures where I live is why I'm looking at using extra heat I'm in Michigan and the actual temperature right now is about 33 degrees so I was going to use my wifes polymer clay ovento add the necessary heat .

Jim Burr

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Reno, Nv

• Mar 27,

• #4

Something to consider Joe, is that as mentioned by Eric, lots of heat is produced by PR curing. A metal mold may be a bad idea...when I do a pour...and yes, I do hard work and make my own blanks, I'll make more for a couple SS votive candle molds. DAMHIKT...but they get hot !!! All that being said...stick with silicone...commercial grades are good to about 400*. I your neck of the woods...start casting in June:redface:?? Last edited: Mar 27,

its_virgil

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Wichita Falls, TX, USA.

• Mar 27,

• #5

I cure my snake skin blanks in an oven at 125. I use 3 drips of nek and have had no problems. My blanks are not brittle...they actually turn quite nicely. I do not use the oven in the Texas heat of summer.
Do a good turn daily!
Don

Marko50

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Oct 22,

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Orem, UT

• Mar 29,

• #6

Go with Alumilite and avoid the drama. I cast all winter long in an unheated garage and my blanks are ready to turn from pour to cure in 3 hours. …Just sayin'

JohnU

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Jan 31,

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Ottawa, Illinois

• Mar 29,

• #7

I pour in my cold IL basement so in the winter I heat the resin in a heat box under a 100 watt lightbulb before I add the catalyst to get it thin and workable. After pouring I set the pressure tank in front of the furnace duct for warm air. Works just fine with no added brittleness. I don't post cute with heat. Sometimes they're a little tacky out of the tank so I put them in sunlight or next to the warm air duct for another hour. Works just fine for me. I also use alumilite, sometimes... but some things just don't work well in alumilite like snakeskins and feathers so other times... PR it is. Good luck! Last edited: Mar 29,

joe966

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Feb 16,

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Livonia, Michigan

• Mar 30,

• #8

I have never heard of Alumilite so I am wondering if it is a clear cast? I saw the alumilite mini casting kit and it looks like it comes out milky white in color.

its_virgil

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Wichita Falls, TX, USA.

• Mar 30,

• #9

Using alumilite is not a cure all casting medium. It works well for some casting situations and not for others. Just saying. We were not told what type of casting the OP is doing.
Do a good turn daily!
Don

Go with Alumilite and avoid the drama. I cast all winter long in an unheated garage and my blanks are ready to turn from pour to cure in 3 hours. …Just sayin'