DavidTodtman Posted May 13, 2014 Share Posted May 13, 2014 I am ready to line my forge with insulation. After a bunch of calling, I found a local supplier for Kaowool (Ceramics Canada, Calgary). They currently have Kaowool rated for 2300F in stock. They have 2600F Kaowool on order and expect it to arrive in about 2 weeks. Can I use the 2300F or must I wait for the 2600F to arrive? David Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 13, 2014 Share Posted May 13, 2014 You can use the 2,300f Kaowool but you'll be replacing it a lot sooner. The 8lb. 2,600f Kaowool is denser and a little tougher under physical assault. That just means it takes a beating better. <grin> However, if you're going to use a hard inner (flame contact) liner and Kaowool as an insulating backer the lower rated blanket is perfectly fine. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
DavidTodtman Posted May 13, 2014 Author Share Posted May 13, 2014 Oh, thanks Frosty! I can wait because I am a grown-up. But, I really don't want to wait for the 2600 stuff. I will certainly use a 'kiln wash'--the place that has the kaowool also sells ITC-100. David Oh boy! I am getting close to getting my forge running! Oh boy! Quote Link to comment Share on other sites More sharing options...
BCROB Posted May 14, 2014 Share Posted May 14, 2014 Oh, thanks Frosty! I can wait because I am a grown-up. But, I really don't want to wait for the 2600 stuff. I will certainly use a 'kiln wash'--the place that has the kaowool also sells ITC-100. David Oh boy! I am getting close to getting my forge running! Oh boy! Hi Dave where in Calgary is the ITC 100 Thanks Rob in Kelowna BC Quote Link to comment Share on other sites More sharing options...
DavidTodtman Posted May 14, 2014 Author Share Posted May 14, 2014 Rob, I spoke on the phone with Ceramics Canada: 403-255-1575. Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 15, 2014 Share Posted May 15, 2014 Rob, I spoke on the phone with Ceramics Canada: 403-255-1575. What's their asking price? Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
DavidTodtman Posted May 15, 2014 Author Share Posted May 15, 2014 What's their asking price? Frosty The Lucky. Hi Frosty, The asking price for the ITC-100 is........ $100.00 Canadian for a pint! At the current exchange rate that'd be about $115 or so USD. I did not get that. I got some kiln wash for $7.00 CDN. I don't really know what I am doing but it seems to have worked as a protective coating on the Kaowool. What do you think of refractory cement. I can get some from the hardware store that is rated for use in furnaces up to 2500F. It's only about $12.00 a pint. David David Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 16, 2014 Share Posted May 16, 2014 That sounds like a bargain price for ITC-100 especially if you add shipping to Alaska. We just bought some zirconium flour and kaolin clay to mix our own kiln wash. ITC-100 is or used to be zirconium sand (about 80) and kaolin clay @ 70:30. What is i the kiln wash you bought? Forge welding fluxes tend to be primarily borax which is caustic when molten so silicates are dissolved quickly. Molten borax eats kaowool like hot water through cotton candy. To protect the forge liner a high alumina refractory is good. High phosphate or phosphate bonded is ideal. Pick kiln washes accordingly, just ask the people at the ceramics/pottery supply. Kiln washes, as such, are used in pottery kilns to keep glazes from firing the pottery to the kiln shelving AND to prevent glaze discoloration in the fire. Pottery folk will usually understand protecting the refractory in the furnace from hot caustics and be able to advise you. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
DavidTodtman Posted May 17, 2014 Author Share Posted May 17, 2014 Thanks Frosty. I do not anticipate welding in my forge. (I have a very nice stick/tig electric welder.) I have said "never" too many times in my life to say I will never forge weld. LOL I will print off and keep your note for future reference (when something that I now cannot remotely imagine arrises and I decide I need to forge weld). The package of kiln wash is not clear as to its contents but states "contains silica" and wear a mask. I will call them and get some more information with the help of you post. Thank you again for your wisdome. BTW, today I ran the forge more than a test run. I forged a pair of tong blanks. The forge performed very well--a whole lot better than heating steel (for beating) with my oxy/propane torch! The tong blanks turned out. They are not elegant but with some grinding and filing, they will work like a hot darn. Not too shabby for a first project out of my forge. Fun! Ciao, David Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 17, 2014 Share Posted May 17, 2014 Sounds like you got hot property! the easiest way I know for finding out what's in a product is to run a MSDS search on the product name. You aren't going to get a formula, just list of ingredients. the idea of MSDS is to allow folk to take reasonable precautions and be able to perform 1sts aid, not give away proprietary recipes. Aw, if you lose your notes give me a shout, I forget notes all the time. I don't remember to take notes and if I do I forget to read them. <sigh> Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
yahoo2 Posted May 25, 2014 Share Posted May 25, 2014 Hi David, I wrote a long tedious boring post about kiln wash when the 4M was having a hissy fit and blocking posts, I thought it had disappeared completely, alas this morning I found a backup copy stuck to some quotes for solar panels and a recipe for chicken laksa. Removing any references to renewable energy and Malay cuisine in an effort to stay on topic, I will attempt it again. Potters have there own shorthand slang that is hard to understand if you are not in the know. I will try and explain the basic principals of Kiln wash for you. A typical shelf coating home recipe will be. 25 grams EPK 25 grams calcined EPK 50 grams Alumina Hydrate 1 grams of perhaps feldspar? If we break it down, EPK is Edgars Plastic Kaolin in other words a kaolin clay that is mined from silt around Edgar in Florida. This clay is basically 1 part aluminium hydroxide 2 parts silicon dioxide and 2 water molecules in the Al2OH3 crystal. The great thing about EPK is that it hold other materials in suspension well and clings to a surface if you dip something in it or paint it on a surface. The problem with EPK is that it shrinks a lot when it is heated to the point that aluminium oxide is formed and the water is released, so it cracks and flakes badly. What potters do to get around this problem, is place a dish of this powdered clay in the kiln when they bisc fire some pottery, this fired clay (calcined EPK) has converted the AL2OH3 to aluminium oxide and therefore does not shrink. Adding this calcined EPK to the mix reduces the shrinkage and eliminates the cracking and flaking. Both the silicon dioxide and the aluminium oxide are refractory materials but aluminium oxide handles higher temperature, so in theory, more is better. This is where the alumina hydrate comes in, it is bauxite, pure aluminium hydroxide (plus some bonded water molecules) So now, in theory if we wash the shelf surfaces and fire the kiln, we end up with a chalky coating that is roughly 70% aluminium oxide and 30% silicon dioxide. The problem now is the fired coating will be very powdery and just rub off as you handle it. The feldspar is added as a flux, so when the kiln wash is fired for the first time, the corners of the crystals that are touching each other will only just melt a tiny bit and fuse together. The end result is a coating that can "only just" be scratched off with you fingernail. This makes it easy to remove melted glaze from the shelves and repair and re-coat the surface but the coating is tough enough to handle daily use and light abuse. The silicates you mentioned are most likely Zirconium silicate (zirconium sand or Zircopax as Frosty has mentioned) added to the mix, obviously this crystal has vastly higher temperature refractory properties than Aluminium Oxide. You will find that most washes and coatings are just a variation on this basic technique. The ingredients may be different to combat oxidising gases, salt, wood gasses or alkaline glazes but what they are trying to achieve will be the same. Hope this is helpful. cheers Yahoo Quote Link to comment Share on other sites More sharing options...
Frosty Posted May 25, 2014 Share Posted May 25, 2014 Yes thank you Yahoo2. I think I'm not as confused now. It sure explains why my home brew kiln wash isn't "firing" to the forge. Do you know of a matrix ceramic that will fire into a more durable state? As a side note, Zircopax is a "brand name" and good search term, not a specific compound, mineral, etc. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
yahoo2 Posted May 26, 2014 Share Posted May 26, 2014 I guess that is why we pay big bucks to the commercial guys. There is a direct tradeoff between the solidness of the surface and the heat it can handle unless you use an expensive extra high heat product in the mix, at that point it is no longer a cheap wash. To put it in perspective a lot of potters refused to use this wash because bauxite has been expensive in the past compared to the price of kiln furniture and fuel. I used to run my mum's kiln for her and I think it took me 10-12 attempts (re-coating about 100 shelves all up) to get all the kinks out of this simple wash. It might be simple but still handles a lot of heat, direct flame not so much. Making a little batch and increasing the flux % will lower the initial melting point, that can be good for patching out the lower temp areas on the first layer (around doors and such) and getting a hard layer. Once that is down and stuck, a second layer of wash with less flux in it can be put over the top. And perhaps a band of the top shelf Zirconium stuff in the really high heat working area. That's just opinion, there is big difference between a gas forge and a kiln and I am no gas forge expert. Too much flux and the crystals stick as a clump then they adsorb heat instead of reflecting it. A flux that does not change state or burn away leaves a residue that keeps remelting the wash every time it is heated. (just like dropping some borax on the surface) Thinking about it, I am not even sure that Zirconium crystals would actually melt and bond to anything, they might just be locked in by the surrounding material. Zircopax is indeed a brand name, as is EPK (it is also the benchmark for refractory style clays), as are 95% of the ingredients in a potters recipe. That is the shorthand, it is easier for them to list a brand product and let the reader look it up in a reference and translate that into the specs needed to substitute another product. yahoo Quote Link to comment Share on other sites More sharing options...
yahoo2 Posted May 26, 2014 Share Posted May 26, 2014 On the subject of brand names, why do we still insist on the name Kaowool? Thermal Ceramics have not had a blanket product with a high temperature rating by that name for a long time. It is cerablanket now. I bet there are plenty of people getting caught with that confusion! Quote Link to comment Share on other sites More sharing options...
DavidTodtman Posted June 1, 2014 Author Share Posted June 1, 2014 Humm.... That is certainly an interesting question. I have been using the word "Kaowool" because that's the word most often used for refractory wool insulation here and at virtually all the websites I have visited to teach myself how to build a forge. It is interesting to note that it was only when I started to call around in Calgary, Alberta that I ran into "cerablanket." Nobody at the industrial shops--this is Alberta with plenty of very heavy industry dealing with high heat thermal processing in the oil sands business!--I communicated with so much as uttered a peep at the word "Kaowool." They did say, however, 'we have cerablanket.' But nobody corrected me for uttering "Kaowool." Conclusion: Kaowool is like "Kleenex" or "Xerox." A brand name that operates in general use. I got what I needed. Just like you would if you said "Please pass me a kneenex." David Quote Link to comment Share on other sites More sharing options...
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