Pr3ssure

Kaowool and Refractory Cement question

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So I'm hoping to start making a propane forge, I enjoy my coal forge and don't intend to replace it but I think for me at least I will be able to get a lot more forging practice in with propane.

Anyway, from all the research I've done I've never really seen anything about types of kaowool and types of refractory. I've never particularly looked very hard honestly. Although in looking to buy some I've just seen some terms I'm not familiar with and haven't been able to find any good/quick and easy info on it. So I was hoping for a little advice. I am probably going to take one of my propane bottles, a grilling one, and cut it up into a forge. For the most part I have everything I need already except for the insulation and the pieces to make the burners, which I drew up a little diagram in my blacksmithing book/journal and laid out all the pieces I will need for them and it should be fairly cheap. Hoping to get my lathe up and running so I can make them proper. I'm wanting to make what I believe is an Australian style burner, like what Alec Steele uses with the round piece threaded over the big reducer as a choke.

Back to the matter at hand, is there any specifics I should know when buying my kaowool and refractory cement? I'm probably going with 2" in thickness but I'm still gonna do some measurements to see how much I need. What types last longer vs how efficient they are and vice versa. Any information on the subject is greatly appreciated, as well as any links to well written articles. I'm reading into most of what I find on google right now but I want as much information going into this as possible so I can do it right.

Thank you all, Pr3ssure.

Also, I'm not sure if refractory cement is the right term or if it's cartable refractory or if the terms are interchangeable. 

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I know you hate it when we just point you at where to read. Too bad. "Forges 101" section on Iforge lays it out in detail.

The term is "castable refractory." Mortar, cement, etc. is not much good in a forge.

Frosty The Lucky.

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alright, I'll look there. I was trying google with "IFI" and you know how that turns out sometimes. Thanks

I'll also check out Wayne Coe 

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Wayne Coe's Build a Gas Forge is pretty much a step by step of what I'm trying to do, so I'll be printing that out. Still reading in the Forges 101 section, I think I'm getting more confused with all the talk of colloidal zirconium and heat reflection. Gonna have to read over this a few times.

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Take things step by step. Your primary concern right now should be shell, lining, burners. Once you have that knocked out, since you've stated you're wanting to use kaowool, then you should look at rigidizing and then protecting the wool.

Now, it's completely possible to use castable instead of kaowool, if you want to trade efficiency for heat retention. Not recommended for most forges as you'll burn through fuel at a much quicker clip. There are a ton of threads here that go back and forth about how to make your own ITC-100 (considered top-tier refractory) to apply once your kaowool is rigidized and your burners are functional and you're happy with everything.

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I've got the shell figured out, unless I get my hands on some cheap/free steel to build a box shaped one. I'm using a propane tank. For burners I've just gotta buy the parts and assemble. I've got a good design to go off of. So I'm just figuring everything out about what goes inside the shell at this point.

After reading, well re reading since I've seen it before, Wayne Coe's Build a Forge I've got a pretty good idea of what I need. I found an 8 foot x 24 inch x 1 inch thick ceramic fiber blanket on amazon, from which I still want to research the brand, for $30. I found a site I can get a 20# bag of kast o lite 30 for $48. Including the material to build my burners that's looking at a bit over $100.

Maybe I'm over thinking it but it feels like that is just too simple. Will probably do another month of research before I decide to buy anything.

Although from looking into the forging 101 I'm confused as to is kast o lite a ridgidizer, if not is it necessary or recommended? The Wayne Coe article doesn't mention ridgidizing the blanket.

Also, is kaowool a brand, if so I've just been using it as a generic term for ceramic fiber blanket. It's what I always hear/read when someone mentions it so I'm not sure.

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Kaowool is a brand, however it's almost like Google at this point, the name becoming the product.

There are threads concerning rigidizing the wool as well. You'll want to rigidize independent of coating with refractory for maximum protection of the wool. However the wool is a consumable, meaning you will need to replace it during the life of the forge. Rigidizing is as simple as buying some fumed silica (available from amazon pretty cheap), mixing it with some water and a few drops of food coloring (to guarantee you're not missing any spots) and spraying the wool with it generously. Depending how generous you are with the rigidizer determines how far down into the wool you are binding the fibers. Makes it easier to apply the refractory later if the wool is a bit stiffer.

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You're reply couldn't have come at a better time. I just got to spot in Forges 101 where it said just that. Although in a more complicated way, so you have helped me understand it a great deal more.

So ITC 100 is something you basically soak the blanket in before putting the refractory, which in turn not only helps to protect it but also helps in the efficiency of heating and keeping the heat in the forge. So I need to add that to my list of things to get.

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So I think I had it backwards, unless I'm just reading conflicting ideas.

So is it blanket, rigidizer, then put refractory or blanket, refractory, then rigidizer.

This is why research is a good idea before diving in head first.

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2 hours ago, Pr3ssure said:

So ITC 100 is something you basically soak the blanket in

NO. ITC 100 is a kiln wash, that's a final coating on the inside of a forge or kiln and ITC 100 isn't really very good for forges. Use Katrikote of Plistex. 

The shell is the container that holds the blanket, etc that makes the forge. The propane tank will be the shell. Yes?

Next comes 2 layers of 1" 8lb. Ceramic wool refractory. Kaowool is a product but is becoming a term for the stuff. It's a high temperature insulating layer made from ceramic fibers. The rigidizer both stiffens it and contains the fibers so they don't break free and drift in your air. The stuff is a breathing hazard and can do permanent lung damage.

The hard refractory comes next and provide armor against both heat, flame and mechanical damage being poked and scraped by work going in and out. Kastolite 30 works well in around a 1/2" layer but some guys like 1/4" others more. I don't think  more is better but I don't make rules here.

The last is a kiln wash painted on about like thick latex paint as a final bit of armor and IR re-reradiator. (meaning it gets really hot and radiates heat back into the forge.

Frosty The Lucky.

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