fireblade Posted February 19, 2009 Share Posted February 19, 2009 Hi all! My name is Ivan and I'm from Brazil. I'm building my first gas forge and fortunately I was able to find out this forum. There are heaps of information here, but I still have a doubt that I think you more experienced guys will be able to solve easily. I'm following the traditional gas forge pattern, a cilinder with Kaowool inside and ceramic coating over it. Actually it Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted February 19, 2009 Share Posted February 19, 2009 ITC -100 is not for sealing the fibers, it is a heat reflective top coat, and should be applied over an under coating sealant, as you have found available in your area. Welcome to I Forge Iron. Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 19, 2009 Share Posted February 19, 2009 Welcome aboard Ivan, good to have you. Unless I'm mistaken I think we have at least one more Brazilian on board. Like Steve says ITC-100 isn't a sealer, rigidizer, etc. for Kaowool, it's an Infrared reflective coating that's applicable to virtually any forge, furnace, etc. Very few outfits carry ITC products here in the states either, we have to order and pay shipping so that option is open. I hope anyway. It's usually best if you can find a source of refractory products locally for availability and repeatability. Look for a coating good to 3,000f and if you can find one that's phosphate bonded or high phosphate all the better as it'll resist flux. If you aren't thinking about doing much welding don't worry about a phosphate refractory. You'll need to give thought to burner size and forge volume as well if you haven't already. Frosty Quote Link to comment Share on other sites More sharing options...
fireblade Posted February 19, 2009 Author Share Posted February 19, 2009 Hey guys! Thanks for the reception and for your reply! Unfortunately, it's virtually impossible to get ITC-100 from a local supplier here in Brazil. Importing from an US dealer would have a prohibitive cost to me. So I think I will have to live without it (at least for the time being). I'm thinking about either using the mortar without such coating directly over fibers or building a forge only with fire bricks. I've found some resources about forges built this way, however if instructions are available, I can't find a word about the results in production. Do you think that the mortar will suffer in such way that I should not even try to use it over fibers without ITC-100? On the other hand, perhaps fire bricks will stand the high temperature, what do you think? Regards, --Ivan Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 20, 2009 Share Posted February 20, 2009 You should seal Kaowool to prevent potential health issues. We were simply pointing out that ITC-100 is different than a rigidizer or stabilizer. You can make a forge from fire brick but brick is a much better heat sink and worse insulator so it will take more time and fuel to bring your forge to a given temp and more fuel to keep it at temp. There is a need to balance efficiency and utility. For the most part, the more heat you can generate and contain for the less fuel the better. However the higher the insulation value of the liner the more fragile it is. Kaowool being very delicate at one end and hard firebrick being tough but a lousy insulator at the other end. There are any number of ways to reach the balance you need or want. For many guys a floor of kiln shelf with the remainder of the forge lined in Kaowool is perfect. Others have brick forges. Some have hybrid liners, a thin inner liner of hard durable refractory covering an outer liner of insulation like Kaowool. These will give you a pretty good compromise though not quite living up to the far end of either range. The hard liner will be far more durable than plain Kaowool though it will be more fragile than solidly backed hard brick. It will be far more insulated and efficient than a hard lined forge though not as efficient as a straight Kaowool liner. I can't answer your question about whether or not a painted on stabilizer will flake off or not, not for sure that is. I'd say yes, it will almost undoubtedly flake from time to time. Will it ruin a piece you're working on? Anything is possible but I seriously doubt it, guys routinely poke their work into burning coke and charcoal which is going to be hundreds or even thousands of times as hard on it as a little refractory flaking off the liner. Look around, make some calls and make a list of all the products and their specs you can find within a distance you are willing to do business over. Once you have the list you can compare them and make your best decision. I do this all the time be it buying a new house, vehicle or looking for spices. If you'd like you can post the list here and we'll look it over and make suggestions as well. Frosty Quote Link to comment Share on other sites More sharing options...
bellman1 Posted February 22, 2009 Share Posted February 22, 2009 Hello Ivan, Sorry to punch in on your thread. This is my first post and I'm not quite sure how to do it properly. So said, greetings to all! Please steer me properly through the fourm so that I don't look like an ass too frequently! Anyhoo, my question: What size oriface range should be used for a propane burner? I built a burner as/per "R Reil" specs. Great burner! I think I should be able to get more out of it. Is there an upper end size oriface, (what would be the max?). Also, what about the regulator? Do I need to get one that isn't just for a gas grill? Thanks in advance. Mark Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 22, 2009 Share Posted February 22, 2009 Welcome aboard Mark, glad to have you. Short answer is yes, get a 0-30psi regulator, a gas grill reg won't put out the psi you need. If that doesn't get it going for you, let me know and we'll talk burner tuning. If you'll click "User CP" at the top of the page and edit your profile to show your location it'll be easier to help you. Folk in your area will be able to tip you to good deals, get togethers and old farts like me wont have to remember who's in the area while traveling if we want a snack or place to nap. Frosty Quote Link to comment Share on other sites More sharing options...
Quenchcrack Posted February 22, 2009 Share Posted February 22, 2009 I have a jar of ITC100 and the instructions say to lightly spray water onto the refractory, fiber or brick, and then apply the ITC 100 by spraying or brushing. It does not indicate that anything other than the water be used to prep the refractory. I will be coating my WhisperBaby forge this weekend and posting the results of the rehab job across the street. Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 23, 2009 Share Posted February 23, 2009 Yep, that's how you do it. If you apply it to a dry surface it'll suck the water out of the ITC-100 and it'll flake off before it adheres. I don't know how it'll spray, it's kind of gritty but if you brush it dab it on or the brush will drag the zirconia flour to the end of the stroke. Let it air dry well before firing it the first time, then give it a good long hot one to cure it. Frosty Quote Link to comment Share on other sites More sharing options...
ChrisB Posted February 23, 2009 Share Posted February 23, 2009 If you look at the sprayers that pottery places sell for ITC you'll see that they are selling a bead blasting gun as a "sprayer". Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 23, 2009 Share Posted February 23, 2009 Ah haahh. The directions I have say to use a spray bottle. I used a bristle brush and daubed it on as evenly as possible but even my largish forge is pretty small. Frosty Quote Link to comment Share on other sites More sharing options...
fireblade Posted February 26, 2009 Author Share Posted February 26, 2009 Hi all! Thanks for your replies. I'm still coming back from my holidays (Carnival ehehehe) , so I'll post my comments today later. ;-) Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 26, 2009 Share Posted February 26, 2009 As soon as your head stops spinning how about clicking "User CP" at the top of the page and editing your profile to show your location, it makes it a lot easier to help folk if you have a general idea where they are. Frosty Quote Link to comment Share on other sites More sharing options...
fireblade Posted February 27, 2009 Author Share Posted February 27, 2009 Hi guys! Following Frosty Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 27, 2009 Share Posted February 27, 2009 Thanks Ivan. Living in Brazil makes a big difference. Outside of efficiency there are a lot of things to recommend a brick pile forge. (Pile of bricks with a burner(s) you can change at need. I keep a pile of fire brick handy for the times I can't get what I'm working on into my "regular" forge. I don't think insulating the outside of a brick pile forge will gain you much in terms of efficiency but it will expose you to airborne fibers unless you contain it. Can you get kaolin clay? If so you can mix it into a med, thin slip to stabilize Kaowool. You'll need to dry it and fire it but that is easy enough in a forge. Kaolin is typically a cone 12-14 porcelain clay that will take plenty of heat. In fact ITC-100 uses kaolin clay as the matrix to hold the zirconia. Then all you need is some light gauge sheet steel for a shell, enough fire brick for the floor and line it with whatever Kaowool you can get. It'll make a perfectly fine forge that will be far more efficient than trying to insulate fire brick from the outside. Frosty Quote Link to comment Share on other sites More sharing options...
fireblade Posted February 28, 2009 Author Share Posted February 28, 2009 Hi Frosty! Thanks for your advise. The idea about kaolin clay sounds good. I'll take a look around here to see where I can buy it. Is it a common thing to find at your location? Besides, when welding metal in the forge, what's the temperature the bricks and the wool will have to stand? Enjoy your weekend! Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 28, 2009 Share Posted February 28, 2009 It should be pretty common almost everywhere, try a pottery or ceramics supplier, that's where I found it. Welding depends on a number of variables. I've seen guys weld easily at low orange heat and other guys like myself at times not get a weld at near melting heat. However, I think most welding is done between 2,500 and 2,700f. (mild steel melts around 2,700f wrought a bit higher) Frosty Quote Link to comment Share on other sites More sharing options...
jimbob Posted February 28, 2009 Share Posted February 28, 2009 Hi Frosty! Thanks for your advise. The idea about kaolin clay sounds good. I'll take a look around here to see where I can buy it. Is it a common thing to find at your location? Besides, when welding metal in the forge, what's the temperature the bricks and the wool will have to stand? Enjoy your weekend! it is what Kitty litter is made from look in a pet store if you can't find it in a pottery store ...might have to put in in a bicket of water to soften it up . you can also put in in a concret mixer with several rocks rhe size of you fist to make into a powder (home made ball mill) Quote Link to comment Share on other sites More sharing options...
Frosty Posted March 2, 2009 Share Posted March 2, 2009 Kitty litter is Bentonite clay not Kaolin. Bentonite is hydrophillic in the extreme and is used extensively in the drilling industry for maintaining down hole pressure, cooling and lubricating bits and carrying cuttings to the surface. Guys are using bentonite in their forges, I think it's because it was used to patch the refractory in cupola melters in the old days, maybe they still do. It might even work for stabilizing ceramic blanket refractories. Kaolin is used for porcelain ceramics, stopping diarrhea and, high temp high precision applications. Different things entirely. Bentonite MIGHT work but Kaolin WILL work for stabilizing ceramic blanket refractories. Frosty Quote Link to comment Share on other sites More sharing options...
knots Posted December 7, 2010 Share Posted December 7, 2010 The Kaolin clay slip seems like a convenient coating supply solution. Since the commercial coating/sealer products usually come in quantities greater than are needed for most forge furnaces and have a short shelf life they are expensive and seem wasteful . Has kaolin slip been used and proven effective for coating ceramic fiber forge liners over time. What would the service temperature range be. I have something like 50 pounds of the stuff and know from experience that shelf life is not an issue if protected from contamination and kept dry. Quote Link to comment Share on other sites More sharing options...
maddog Posted December 8, 2010 Share Posted December 8, 2010 I would go with a porcelain slip or add extra alumina to the kaolin. You can get it cheaply from the pottery supply houses. I expect it will be very friable. Cracks in the coating expose the wool to hot gas which damages it quickly. The only coating that I know of that will hold together as a thin layer is Plistix 900. I like the refractory inner liner with 2" kaowool or some other high insulation value material for the outer layers. Its a little slower to heat up but much more durable. I also use scrap kaowool or soft firebrick rubble for the outer layers. All the forges I have built with wool as the inner liner needed constant maintenance. If you are just forging blades I guess it's ok but when you have bendy pieces going in and out, protecting the liner is difficult. Quote Link to comment Share on other sites More sharing options...
knots Posted December 8, 2010 Share Posted December 8, 2010 I would go with a porcelain slip or add extra alumina to the kaolin. You can get it cheaply from the pottery supply houses. I expect it will be very friable. Cracks in the coating expose the wool to hot gas which damages it quickly. The only coating that I know of that will hold together as a thin layer is Plistix 900. I like the refractory inner liner with 2" kaowool or some other high insulation value material for the outer layers. Its a little slower to heat up but much more durable. I also use scrap kaowool or soft firebrick rubble for the outer layers. All the forges I have built with wool as the inner liner needed constant maintenance. If you are just forging blades I guess it's ok but when you have bendy pieces going in and out, protecting the liner is difficult. Well I called the Plibrico Company, the manufacturer of PLISTIX 900, this morning. their telephone has been disconnected. It appears that another good company has gone belly up. My problem with most commercial products is that you have to purchase the products in quantities that grossly exceed my needs. The unused product has a short shelf life, consequently I usually throw away more than I use. This seems very wasteful. So I need to find or create a dry product . All that I need is to seal my forge furnace, so the Kaolin slip idea is still an attractive alternate. MD your recommendation of mixing alumina with kaolin is the basic formula for porcelain clay body or slip except that bone ash is some times also included as a flux . Bone ash is a source of phosphorus so it makes sense to consider adding it in some proportion to your proposed mix. Could be that the addition of bone ash would reduce the friability and tendency to crack. I think I will order some up and run a few tests. Quote Link to comment Share on other sites More sharing options...
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