Flint762 Posted March 17, 2017 Share Posted March 17, 2017 When using ceramic fiber board for a forge what is the minimum thickness that it must be? I have a 24 x 18 x 1 inch board and I would like to make a single burner forge. I was going to use a 1.25 thick hard fire brick for the floor of the forge. Can I use the fire brick the back up the board and will the 1 ich board stop heat transfer to the brick and outer walls? Thanks Flint762 Quote Link to comment Share on other sites More sharing options...
Frosty Posted March 17, 2017 Share Posted March 17, 2017 Welcome aboard Flint glad to have you. If you'll put your general location in the header you might be surprised how many of the Iforge gang live within visiting distance. I have 1 1/4" hard fire brick for the floor in my shop forge and after using it for years wish I'd used something else. High alumina kiln shelf would be my next floor if I weren't retiring that old thing. I'm not sure just what you asked next, how close am I. You want to know if you can use brick as a backer outside the ceramic board? That answer is not just yes but HECK yes! The only problem with ceramic fiber board inside a forge is it's pretty fragile at temperature and hot welding flux dissolves it like hot water on a sugar cube. UNLESS you have one of the high alumina or phosphate bonded ceramic refractories. You can easily apply a layer of high alumina hard refractory as a flame face to protect it from mechanical abrasion and flux erosion. A final kiln wash, ITC-100 being the best known but not only good IR reflective wash will up the efficiency another notch and make it much more resistant to fluxes. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Flint762 Posted March 17, 2017 Author Share Posted March 17, 2017 Thanks Frosty. So 1 inch of the fiber broad will be enough insulation if I use 1.25 inch of hard fire brick out side of the board? I am concerned about heat transfer to the out side of the forge Flint762 Quote Link to comment Share on other sites More sharing options...
WayneCoeArtistBlacksmith Posted March 18, 2017 Share Posted March 18, 2017 ITC-100 costs about $75.00 a pint, Plistix is $15.00 a pint and Metrikote is $20.00 a pint. I have used all three and all three work. I have not done any side by side tests but in the uses that I have experienced they all work about the same. What shape is the forge you are building, do you have any other products that you are planning to use? Have you read the attachment Build a Gas Forge on the Forge Supplies page at www.WayneCoeArtistBlacksmith.com? If you are building a round forge I would cut the fiber board to size for the floor with a small piece underneath to fill in the void, then wrap the upper portion with Inswool, cast over all of that with Kast-0-Lite then after that has cured paint over it with a coat of Plistix or Metrikote. The Kast-0-Lite is resistant to flux and will give you a good tough, strong, long lasting forge. The Plistix or Metrikote will reflect the IR back into the forge increasing the efficiency. Let me know if I can help you. Wayne Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted March 18, 2017 Share Posted March 18, 2017 I would not use the board for a forge's side walls, which can be made just as well from much cheaper ceramic blanket. The board is no better insulation than the blanket; its point is that it is much tougher than the blanket at heat, which makes it a better choice for the near and far ends of the forge, and considering how much more money it costs, I can only consider using it for the walls a BIG WASTE of the material. The board is also could for insulation under s kiln shelf floor. Quote Link to comment Share on other sites More sharing options...
WayneCoeArtistBlacksmith Posted March 18, 2017 Share Posted March 18, 2017 In my reply I was assuming that he already had the board. As Mikey said it is no better than ceramic blanket and costs more so unless I had already picked up the board I would just use all blanket with a casting about 1/2" thick over that and then a coating of Plistix or Metrikote. Let me know if I can help you. Wayne Quote Link to comment Share on other sites More sharing options...
Frosty Posted March 18, 2017 Share Posted March 18, 2017 Flint says he already has a piece 1" x 18" x 24". Personally I'd use it for the lid so I wouldn't have to worry about it drooping. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Flint762 Posted March 19, 2017 Author Share Posted March 19, 2017 Thanks for all the info folks. So if I build the forge with a inside measurement of 5 inches wide by 5 inches high and 9 inches deep would work for a single natural aspirated burner. I was thinking of working out from my measurement and I was worried that I would get to much heat lost through only 1 inch of ceramic board that will be treated. For the outer walls I was thinking of 16 ga. sheet metal and I want to be able to take the forge with me when I go camping so if I can keep the weight down all the better but it needs to be safe as to not heat up surroundings. I am new to blacksmithing and have been using a paint can forge but the lining started burning out so this is why I am looking for a new forge and asking all these novice questions. Flint Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted March 19, 2017 Share Posted March 19, 2017 You will end up with a forge that needs no more than a single 1/2" burner. I would suggest using a two gallon non-refillable Freon (or Helium) cylinder to make your forge shell with, instead of the smaller shell you seem to be considering; this will allow you the added room needed to use a 2" thick layer all around the inside of your forge. This size forge has been used and recommended endlessly over the last two decades; there are many reasons for this, beyond the obvious ones that come to a beginner's mind. In front of my house sets an old car I waited for twenty years to get my hands on. I could set down and list the many things I admire about it, but in stead I just says, over and over, "I just love this car"!!! Users all over the world feel that way about this forge design; get the message, and build something that makes you say "I just love this forge"...or not; you have received the advice you need; the ball is in your court. Quote Link to comment Share on other sites More sharing options...
buck369 Posted January 14, 2023 Share Posted January 14, 2023 Hi, i recently bought a cast masters smelting forge and trying to insulate it with the ceramic fiber blanket. I applied rigidizer first, heat treated it like the instructions stated and it became like stiff cardboard layer then applied satanite refracyory with 2 coats but each coat is cracking. I wanted to use itc 100 for the last coat but i dont know if i should scrap this and start over and maybe use fiber board instead of blanket. I believe its cracking because the blanket is able to flex but dont quote me. I just need some advice. Thank you. Quote Link to comment Share on other sites More sharing options...
Frosty Posted January 16, 2023 Share Posted January 16, 2023 Repeating the same question in multiple threads won't get you a better or faster answer. I replied in your other post if anybody disagrees or has other maybe better ideas a discussion will ensue. Good to have you aboard. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
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