Insulation question.

[RDSBandit]

I am building my forge here at home and am planning on useing a 5 gallon bucket for the body. And I have a couple of questions.

1) Is there a best brand of ceramic insulation? Like, will Kaowl wool give me the best results on forge tempature? Or are they all pretty much the same?

2) I think I understand the refractory cement a little bit. You put it on top of the ceramic fiber to help keep it from getting burnt up by the burners. But, does it also kind of act like a glue? If I am planning on putting two layers of one inch thick ceramic fiber in my forge, do I need to put the refractory cement on the very bottom, then between the two layers, and finally a third coating on the layer that will be exposed?

3) If refractory cement isn't the glue, then what do you use to keep the wool in place?

[Frosty]

You buy ceramic wool refractories by specification, different brands are available in different places but most are comparable. I use 1", 8lb at as high temp rating as available. Last I got was 2,600f but anything over 2,300f is fine with a good kiln wash. I use Kaowool because that's the brand I can get at the closest furnace supply place. E.J Bartells by name. Great guys, love fire and know their stuff.

What shape forge are you making? Unless it has a flat roof you don't need anything to keep it in, just cut it a little large so you have to stuff it in a little. It'll hold itself in.

Refractory cement is NOT properly used to cover the hot face in a forge, it's only to stick things together. Use a proper kiln wash to protect the liner. There's been a couple pretty in depth threads recently about just this, you might want to check them out then get back if you have questions.

Try to filter out the new guys who want to be helpful and or get their information off Youtube, etc. This is the main source for poor solutions to easy problems. If you really want the hard data on making and lining forges hit the library and check out a book on building pottery kilns. There is more GOOD info than a boy could want rattling his brain in a basic kiln book.

Frosty The Lucky.

[jcornell]

On 3/21/2016 at 8:14 AM, RDSBandit said:

I am building my forge here at home and am planning on useing a 5 gallon bucket for the body. And I have a couple of questions.

1) Is there a best brand of ceramic insulation? Like, will Kaowl wool give me the best results on forge tempature? Or are they all pretty much the same?

2) I think I understand the refractory cement a little bit. You put it on top of the ceramic fiber to help keep it from getting burnt up by the burners. But, does it also kind of act like a glue? If I am planning on putting two layers of one inch thick ceramic fiber in my forge, do I need to put the refractory cement on the very bottom, then between the two layers, and finally a third coating on the layer that will be exposed?

3) If refractory cement isn't the glue, then what do you use to keep the wool in place?

For the ceramic fiber, you'll look at temperature rating, density, and then you'll also need to pay attention to whether the fiber is water soluble (Superwool HT) or non-water soluble (kaowool etc.).

If you can, go with the water soluble fiber - it's less irritating and over the long haul, it's a little bit safer.

[Frosty]

5 hours ago, jcornell said:

For the ceramic fiber, you'll look at temperature rating, density, and then you'll also need to pay attention to whether the fiber is water soluble (Superwool HT) or non-water soluble (kaowool etc.).

If you can, go with the water soluble fiber - it's less irritating and over the long haul, it's a little bit safer.

Good point J. another benefit is water soluble isn't a lung hazard unless you inhale clouds of the fibers. I have GOT to remember the option.

Thanks for bringing it up.

Frosty The Lucky.

[timgunn1962]

The soluble stuff is more usually termed body-soluble or bio-soluble. I don't think it's intended to be water-soluble per se, but it will supposedly dissolve (quite slowly) in body tissue and should therefore present less of a long-term risk to health than insoluble fibers. I assume it'll be a few decades before there is hard information on the relative long-term health effects of both types. In the meantime, industry seems to be following a precautionary principle and going bio-soluble where practicable.

I think the body-soluble stuff had a maximum temperature rating around 2300 degF last time I looked into it, which left the insoluble stuff as the material of choice for welding temperatures. It was a few years ago and things may have moved on since.

 

 

[jcornell]

3 hours ago, timgunn1962 said:

The soluble stuff is more usually termed body-soluble or bio-soluble. I don't think it's intended to be water-soluble per se, but it will supposedly dissolve (quite slowly) in body tissue and should therefore present less of a long-term risk to health than insoluble fibers. I assume it'll be a few decades before there is hard information on the relative long-term health effects of both types. In the meantime, industry seems to be following a precautionary principle and going bio-soluble where practicable.

I think the body-soluble stuff had a maximum temperature rating around 2300 degF last time I looked into it, which left the insoluble stuff as the material of choice for welding temperatures. It was a few years ago and things may have moved on since.

 

 

Superwool HT is rated  for 1300°C (2372°F) (Per the manufacturer's data sheet) while Kaowool S (the standard version) is rated for 1260 c (2300F).  You have to get up to Kaowool SZr to get to 1425 C/2597F.  Good luck finding someone who carries Kaowool SZr.

Prior versions were not as robust, but I've been using it successfully for a while, although my latest build was plain old kaowool, because that's what I had on hand..