Hunter Ray Posted October 9, 2015 Share Posted October 9, 2015 Hi my name is Hunter and I'm 15. I recently built a new L.P. gas forge and bought some ceramic fiber insulation. While I was reading some other post on this site and other site I got the impression that I would also need to buy some cast refractory cement. So basically what I'm asking is do I have to cove the ceramic fiber with refractory cement or not. Thanks for the help on advance. Quote Link to comment Share on other sites More sharing options...
NickOHH Posted October 9, 2015 Share Posted October 9, 2015 I'm not expert in this area as I'm building my gasser now, but you are insulating it to keep heat in so the more(to an extent) insulation the better. I am just planing on using kaowool, and coating it with a kiln lining hardener such as itc100. Some people just throw the fiber blanket in there and light it up. I'm not sure about refactory but it would do the same as the itc100 in a way, reflect heat back away from the blanket towards the center. Quote Link to comment Share on other sites More sharing options...
jcornell Posted October 9, 2015 Share Posted October 9, 2015 If you bought Kaowool, you'll definitely want to cover it with something to insure that you're not breathing ceramic fiber shreds as you stand in front of the propane forge. If you bought Superwool (water soluble) it's not as critical.I've always covered the fiber with something. I use a home brew mix of zircopax and kaolin which is a nice reflective coating that provides a bit of protection. Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted October 9, 2015 Share Posted October 9, 2015 Not only are you protecting yourself from stray fibers you are also protecting the insulation from damage. The addition of an IR reflectibe kiln wash also ads to your fuel effecency. So long turm peraonal safty, durability and effency. Quote Link to comment Share on other sites More sharing options...
Hunter Ray Posted October 10, 2015 Author Share Posted October 10, 2015 Ok so I guess I should start saving then thx for the help Quote Link to comment Share on other sites More sharing options...
natenaaron Posted October 10, 2015 Share Posted October 10, 2015 I hope hunter does not mind if I piggy back on his thread. Would a person put rigidizer on the insulation before the ITC 100 or is it fine to just use the ITC 100? I am about to order one or both but if it is not necessary have the rigidizer then I will just order the itc-100. Quote Link to comment Share on other sites More sharing options...
Frosty Posted October 10, 2015 Share Posted October 10, 2015 Welcome aboard Hunter, glad to have you. If you'll put your general location in the header you might be surprised how many of the IFI gang live within visiting distance.Don't get carried away with washing the ceramic blanket, a good kiln wash is plenty. Use a piece of kiln shelving or split fire brick for the floor to limit damage from hard, pointy steel poking into the forge.Ceramic blanket is a wear item, it WILL wear out and you WILL need to replace it after time. If you use 2 layers of 1" 8lb. blanket it will give the forge a smoother contact surface with fewer heat shadows and easy things to snag. It also makes it a LOT easier and cheaper to replace, the contact layer being just the inside 1", it'll peal right out ad you can press the new one in. Wash and go to work.Keeping vitrified ceramic fibers OUT OF YOUR LUNGS is important. VERY. Kiln wash it.Yes Nate, use rigidizer first. It reinforces the ceramic blanket. ITC-100 is very resistant to fluxes and is a strong IR reflector but not physically tough or stiff.Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted November 20, 2015 Share Posted November 20, 2015 Ceramic fiber wears out because of linear shrinkage from heat cycles, and from a serious tendency for the layers to delaminate from each other. But the worst wear factor is the tendency of the fibers to form crystabolite particles at 1600 F. All these problems are seriously reduced by using rigidizer, which works by coating the fibers all over; this locks the fibers in position where the cross each other. the major content in Rigidizer is water, which steams away during heat curing, leaving a pretty thin layer of silica. So, loss of insulating qualities is minor while strengthening is major. A rigidized layer also makes good support for a thin refractory layer (1/4" is good). In turn, the nice smooth hard refractory layer becomes a perfect support for an infrared "reflective" layer, such as ITC 100, and also allows that layer to be thinner ($$$$ saved). Quote Link to comment Share on other sites More sharing options...
WayneCoeArtistBlacksmith Posted November 20, 2015 Share Posted November 20, 2015 Hunter, check out the attachments at www.WayneCoeArtistBlacksmith.com at the Forge Supplies page. This is the way that I like to build a good, strong, long lasting, efficient forge. Let me know if I can help you. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted December 5, 2015 Share Posted December 5, 2015 jcornell jcornell, I like your idea of a "home brew mix of zircopax and kaolin for a tough hard high IR "reflector" coating better than anything else I've heard. Zircopax is basically zirconium silicate (probably with a temporary binder ingredient added). The point of zirconium silicate instead of zirconium oxide is that it amounts to a form of stabilized zirconium (which is otherwise expensive) silicon is a common ingredient used to help bind (and vitrify) refractory mixtures together, and is fairly tough and heat resistant. Kaolin clay is another inexpensive tough heat resistant binder ingredient in refractory mixtures; together they should produce an ideal high emissivity coating and fiber sealant. What proportions do you use? Quote Link to comment Share on other sites More sharing options...
jcornell Posted January 15, 2016 Share Posted January 15, 2016 Approximately 4:1 Zircopax to Kaolin - four measures of zircopax to one measure of Kaolin. It seems to work. Quote Link to comment Share on other sites More sharing options...
Frosty Posted January 15, 2016 Share Posted January 15, 2016 ITC-100 is 70% kaolin 30% zirconium silicate. I"m not the person who did a hydrometer fraction to determine the ratio but believe the fellow who did was accurate enough to use his numbers as a good close approximation. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted January 16, 2016 Share Posted January 16, 2016 Frosty, What you brought up here is interesting. I've had strong hints from others local to my area (Puget Sound) that among other dissatisfaction with ITC-100, at least some local dealers were "cutting" the formula with their own additives. That isn't something that is easy to control, and I don't wish to waste personal time playing policeman, but it's something to keep in mind... Quote Link to comment Share on other sites More sharing options...
ianinsa Posted January 16, 2016 Share Posted January 16, 2016 1 hour ago, Mikey98118 said: Frosty, What you brought up here is interesting. I've had strong hints from others local to my area (Puget Sound) that among other dissatisfaction with ITC-100, at least some local dealers were "cutting" the formula with their own additives. That isn't something that is easy to control, and I don't wish to waste personal time playing policeman, but it's something to keep in mind... We have plenty of shenanigans down here in Africa but thankfully 'They' haven't started cutting the kiln wash. Quote Link to comment Share on other sites More sharing options...
Frosty Posted January 16, 2016 Share Posted January 16, 2016 ITC products priced themselves off my radar a few years ago so I've been playing with my own mixes. Happily you're input about needing to stabilize it and phosphate being a good stabilizer means my next experiment will be with a 3,000+f. phosphate bonded castable refractory. I can get those locally and I have good scales. I may take my oxy propane torch to test coupons and see how it reacts to 4,700+f. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Ironhawk Posted January 17, 2016 Share Posted January 17, 2016 Mikey98118 I'm also in the puget sound area just fyi. Don't mean to jack this thread but it looks like a good one as I am also currently building a propane forge. I plan on using refractory cement for my lining and dual homemade venturi burners. Is the refractory cement a good go to or should I just stick with koalwool? I plan on forge welding Damascus so I figured the cement would last longer. I am basically following another puget sound smith's design for my forge. Quote Link to comment Share on other sites More sharing options...
jcornell Posted January 17, 2016 Share Posted January 17, 2016 I don't know what type of refractory cement you have, but mine was terrible. It cracked and peeled like a bad sunburn. Look at Wayne Coe's website for a decent cookbook - I have a way smaller forge, so I don't go for such a level of refractory - I have zircopax/kaolin on top of superwool with rigidizer. Quote Link to comment Share on other sites More sharing options...
Ironhawk Posted January 17, 2016 Share Posted January 17, 2016 What did you use? I plan on using kast-o-lite 30. Supposed to have a good alumina mix and has a 3000deg. Rating. Quote Link to comment Share on other sites More sharing options...
Frosty Posted January 19, 2016 Share Posted January 19, 2016 Kastolite is a good choice but cast it, don't smear it on with a putty knife. I used sonotube one with an outside diameter that was what I wanted the ID of my forge to be. I placed it in a sonotube with an ID 3/4" larger than the other tube. This gave me an annulus (space) of 3/4" which I rammed up with my hard refractory liner. Once set I pealed the outer sonotube off and dropped a couple burning charcoal briquettes inside to burn the inner sonotube out. Once it'd cured up well I wrapped it in Kaowool and slipped it into the shell. It's easier than it sounds, really. Not that it matters but I was born in Everett and have or had relatives living all over the Pacific NW. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Ironhawk Posted January 19, 2016 Share Posted January 19, 2016 Frosty- Thanks for the info. Yeah I will definitely be casting it. My plan however was to cast it directly into my forge body using sonotube for the ID and casting it 2"thick and forgoing any koawool. Not sure if that's a good way to do it or not, that was the way I saw it done recently. Cool deal. I'm fairly new to the area. Been living up here for close to 4 yrs now. It's real pretty but there is a few too many people. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted January 19, 2016 Share Posted January 19, 2016 /A hot-face layer 2" thick?!? You might as well use hard firebrick; it's going to end up as a heat sink! Quote Link to comment Share on other sites More sharing options...
Ironhawk Posted January 19, 2016 Share Posted January 19, 2016 that's why I was asking. I wasn't sure about the use of refractory like that and had seen it done but was unsure of its efficiency in that use. So I would be better off using kaowool wrapped around a thinner shell of refractory or just using kaowool with a stiffner. Thanks for the info. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted January 19, 2016 Share Posted January 19, 2016 Okay, once we avoid the extremes, "better off" starts becoming a very flexible concept. Generally (if you know what You're doing) a thicker hot-face is stronger and therefore better lasting than a thinner one, but at the cost of fuel efficiency. Thinner hot-face layers transfer more heat to the secondary layer of insulation, and if that secondary layer isn't capable of handling the higher heat transfer, it won't last long. BUT: How much heat the tot-face receives at a time is up to the operator. Let me make this very clear; how much heat that each and every layer your forge has to manage depends on how far you turn up the f-l-a-m-e in your equipment; obvious isn't it? Or, is it? How many times have I seen overlarge heating chambers putting out white heat, while someone pounds on a small part? Nobody works steel at white heat so what is the point of all this...waste. Maybe the guy isn't aware of it, but waste is what he is producing. Wasted fuel, along with wasted wear and tear on the equipment. When I started designing burners the "more is better" debate was going on; then it was in the form of naturally aspirated versus fan-blown burners: "which is hotter, which is hotter?" We hardly ever heard anyone asking which can waste more fuel, did we? As I worked to build ever hotter burners, I also worked to build them ever smaller. Way back when, hotter burners mattered hugely, because most of the designs around were marginal; they had to struggle to do the job, right? WRONG; burners then only had to struggle if they or the equipment they powered weren't built right, and tuned right. So, what all this means to you is, you want to consider how hot and how often you're going to work steel. Maybe a thin coat of zirconium rich refractory over ceramic fiber makes great sense for what you want to accomplish, and maybe a 1" thick kast-O-lite 3000 hot-face layer over a secondary layer of 2600 simi-insulting castable is the ticket for you. Or one of may options somewhere in between. What then is the biggest difference between these two extremes? Aboout ten extra minutes heating time... Quote Link to comment Share on other sites More sharing options...
Ironhawk Posted January 21, 2016 Share Posted January 21, 2016 Thanks for all the info! This gives me a better understanding of the direction I want to take. I wasn't sure about the use of refractory like that and had seen it done but was unsure of its efficiency in that use. I will price some different ways to go in my area and see what will be readily available and go from there. Definitely think I will rethink my layout though. Quote Link to comment Share on other sites More sharing options...
Frosty Posted January 21, 2016 Share Posted January 21, 2016 Thanks Mike, I lost track of the 2" hard inner liner. Back in the days when folk were trying to come up with a home made gas burner that was adequate but didn't cost like a commercial one, enough was the goal. Unfortunately a human trait is to invest themselves in "the quest". Most people didn't grow up with parents that pounded their own version of "more is better" into them. In our family it was, "More MIGHT be better but probably isn't." It's okay to push the envelope but expect it NOT to work and test test test. A 2" hard inner liner is probably exactly what you need if you are working billets weighing hundreds of lbs. and it needs to take serious physical abuse at temperature and have a fast recovery time for returned billets. My first successful pipe forge has a 3/4" high phosphate hard refractory inner, "flame contact" liner surrounded by 1" of 8lb. Kaowool. It's a good 25yrs. old and still competent I just don't use it. My shop forge suits my needs better. Do NOT fall into the trap of trying to make the PERFECT forge or heck ANYTHING first off. Us old timers have old forges of all kinds tucked into corners, back sheds or where ever because we tried to make the perfect forge or whatever. Build something that will work for what you want to do to LEARN the craft. Once you develop your skills you'll develop a product line and personal methods and only then will you be getting to a point you can make a forge that'll last you years. No it still won't be perfect but it'll be much better maybe even close. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
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