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Curing Kast-O-Lite 30

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Hi all, next step in my forge setup is to apply Kast-O-Lite 30 on top of my rigidized Kaowool.  Question: Is there any concern (outgassing or otherwise) with doing the initial heat treat of the Kast-O-Lite 30 up to 500deg in a kitchen oven?  I've seen various methods (kiln, dedicated shop oven, bulb, fire, low flow burner, etc.) that people have published, but I was thinking to do the initial cure very controlled in the kitchen oven and then do it the rest of the way with the propane burner.  Am I crazy, because I haven't seen anyone else post about doing this (perhaps there is a good reason)?  And yes, it will fit as it is a very small single burner forge.

Thanks in advance.

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Is this "Kitchen Oven" inside your house and the very same oven you use to cook with?

If so, DON'T DO THAT!!!

Any idea what's in KOL30?

Ever heard of a MSDS?

Not jumping down your throat but people need to research topics before asking questions they already have access to the answers.

Bottom of page for Manufacturer curing instructions.



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Hi idk, thanks for the quick feedback.  No worries on the perceived tone of the feedback, I'm learning to grow a thick skin on here. :). I did do some research but didn't feel as if I found a satisfactory answer, so I thought I'd pose the question to the experts (materials and smithing) to get more clarity.  I do have the manufacturer's curing instructions, which is why I thought of the controlled 100deg/hr capability of an oven as opposed to the less controlled other methods I read about.

I had seen this method mentioned in two other places (see attached), including one of the experts here posing it as a hypothetical question (though I can't find that post again).  Other than that, I never saw anything saying it's an absolute no-no, so I figure it doesn't hurt to sound stupid and ask again.  Glad to did.  

I did look at the MSDS, though I'm not an expert in reading them so I didn't see anything as outgassing hazards.

But again, I very much appreciate the feedback.



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The only thing I could find on the MSDS was a vague mention of a cancer risk associated with long term exposure.  I don’t remember if it was on the document or somewhere else but it seemed to be specifically about people working around furnaces and kilns using the stuff at the industrial level.  I was assuming it was the dust from created by daily use over years.

Personally, when I do it, I’m following the advice mentioned by the big dogs and starting it off with a bulb for a few days or more.

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I've not used Kast-O-Lite yet, but have used the domestic oven for drying out small single-burner forges. Reasonable safety precautions need to be taken: I do it when my other half is out for the day.

Assuming you have not introduced anything nasty with the shell (paint, oil, etc, depending on the source of the shell) or with your rigidizer (surfactants?), you "should" have no problems at all. 

As far as I can tell, the KOL does not need to be "cured" with heat, as it undergoes its chemical changes at room temperature. The slow heating schedule is simply to dry it out.

I weigh the forge once I've left it for as long as I can to air dry (usually weeks here in Lancashire. Austin should be much quicker). I weigh it every hour or 2 during the oven drying. When it stops getting lighter, I give it another hour with the oven on full and call it dry.

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When you say cure, what exactly do you mean? Kastolite products undergo TWO cure cycles. The first one is when you mix it with water, first it sets by hydrating. It does NOT dry, it sets like portland cement concrete and then it should go through a proper cure at 100% humidity and room temperature for at least 24 hrs. 7 days is better.

Once it's set and cured heat curing isn't a bad idea but 500 f. isn't going to do it. Cure is 900 f. -  1,000 f. A prolonged 1,300 f. cure is desirable in some applications.

For what we do cure it at 100% humidity for 24 + hrs. Allow to dry fire the burner for a couple minutes to drive off residual moisture from cure cycle. Bring it to dull red heat and let it cool. Then put it to work.

The cancer warning is because some of the aggregate used may contain silicates and all their aggregates are crusher run. Sharp silicates are a known carcinogen so they warn you according to Gvt. regs. Don't eat it and it's kind of base so it can irritate your skin, eyes and such.

Frosty The Lucky.

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Tim and Frosty, sorry for the lazy use of the term cure.  in this case I am using "cure" as a general term for any heat treatment (I guess it more applies to the food industry where curing by dehydration is just moisture extraction) rather than the more technical term for a chemical transformation.  I work in the semiconductor industry and use that term generically for any thermal or UV treatment.  But yes, more correct in this case would just be drying or heat treating, so I'll use the more appropriate term from here on out.

The 500F number was simply (a) what I could get to in my oven, and (b) what Wayne Coe uses for his drying process.  Since the manufacturers recommended schedule is approximately 100F - 1000F at 100F/hr, I figured that first 500F being controlled is pretty important to get that moisture out and then the final 500C with the propane burner is on a wing and a prayer.  But then again, I've also read that this stuff is super forgiving and tough, which seems to be why all manners of drying work.  No worries, I won't overthink this and I'll get to drying this weekend.

Thanks again.

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