Resin casting Question

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treker2557
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Joined: Sun Apr 06, 2008 7:49 pm
Location: Olyphnat Pa

Resin casting Question

Post by treker2557 »

I was just wondering what are the advantages to using a urethan protectant such as Freeman 302 Urethan Protectant that uses an inert gas of
1,1,1-tetraflouroethane. Can you just use an inert gas such and nitrogen?

My understanding is that after you spray your resin casting immediately after opening your pressure chamber and then seal it again for several minutes. And that this is supposed to increase it's life and strength?
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Johnnycrash
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Post by Johnnycrash »

This gas system, or any inert gas, is designed to minimize the amount of moisture than can leech into the resin BEFORE casting.

Once you break the seal on the containers of Part A, and Part B, the resin begins to absorb moisture from the air. By removing the air, and replacing it with an inert gas, it limits the amount of moisture the resin is exposed to, and therefore reduces the amount of absorption.

It is NOT for the resin after casting, but for the two part chemicals BEFORE casting, while storing them.
John Fleming
I know that's not what the instructions say, but the kit's wrong anyway.
treker2557
Posts: 42
Joined: Sun Apr 06, 2008 7:49 pm
Location: Olyphnat Pa

Post by treker2557 »

Thanks for the help. I just placed an order for a large scale pressure pot 5 gallon and purchased supplies to make a vacuum chamber lid and bought a 6 cfm vacuum. Myself and a friend are just getting into researching everything and I got confused on what the protect ant was for.
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Johnnycrash
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Post by Johnnycrash »

No problem. Glad I could help. If you use your resin quickly, or semi-fast, you don't need to do that. Just make sure you can seal the containers well.

For your vacuum pump, how much air it can move is not all that important. How strongly it can pull that air, that is what you need to know. For degassing rubber, it should be able to pull at least 29" of mercury.
John Fleming
I know that's not what the instructions say, but the kit's wrong anyway.
OdysseySlipways
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Post by OdysseySlipways »

treker - what's wrong with using the stock tank lid? i use one of my 2 gallon pressure tanks as a vac tank as is (other than plugging all of the opening)

and just where in Pa are you?
Chris,
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