Archie Otteson Posted August 2 Share Posted August 2 I've put less than 10 hours fire time on this Forge. IFB2800° with 3000° refractory mortar between the bricks. Dual frosty-T's indexed straight down with 1/4" burner tip exposed inside the forge chamber. The roof is crumbling and caving in. It's primarily around the burner holes inside the roof. Other roof bricks are cracking through. Can the bricks be repaired with mortar or be replaced? What is going on here? I feel like there is a design flaw. Quote Link to comment Share on other sites More sharing options...
Archie Otteson Posted August 2 Author Share Posted August 2 I suppose reading ahead might have helped with my question. Yes, I'm stubborn and easily distracted. Soft IFB in gas forge being a consumable and seemingly fragile why is it so popular? What is a good method for extending IFB's life span? Is hard fire brick a better choice? Does the wool blanket material have a longer life span? What is the most durable insulation for a gas forge? Quote Link to comment Share on other sites More sharing options...
swedefiddle Posted August 2 Share Posted August 2 Good Morning, You are learning the reason why most of us have more than one Forge. Most of us have gone through the brick Forge phase. To answer your question, there is not 'one' simple answer. Yes, I went through the soft brick phase, multiple times. I used hard brick for my Forge, for about 10 years. I never used mortar to hold the bricks together, they sit nicely all by themselves. No, I was never trying to weld, I was Forging. It took about 15 minutes for the hard brick to come up to temperature and the temperature stayed steady. We tied 2 -100lbs tanks together and it took about 6 hours before we had to stop work with frozen tanks. That never bothered me, by then It was time for a Break!! The last time I counted, I think there are 15 Forges in my Shop. My favorite is the Induction. It is expensive to start, but by far it is the least expensive to operate and maintain. It can be asked to do many different configurations. It is quite peculiar, it doesn't heat the Shop, like all the Coal/Coke/Propane Forges. There is no such thing as Perfect!! Perfect for what????? Use whatever it takes to get the job done, forget about asking for permission, JUST DO IT!!! Neil Quote Link to comment Share on other sites More sharing options...
Latticino Posted August 2 Share Posted August 2 The main problem is that you have tried to use an insulating material for construction and support. Your "roof" wasn't even fully supported by a full width of block. Also, as you found out, these insulating bricks are quite fragile, particularly after firing up to temperature and repeated thermal cycling. It is possible to build a forge using light weight bricks, but the forge frame needs to be designed to keep the bricks under light compression and fully supported by a full width of brick. Note that direct flame impact will also melt the surface of an insulating firebrick and refractory mortar may not save that. Here is a sample, tested brick forge design from Giberson's site (note the compression on the lid): Personally I've had the best success lining my forge with 2" of 2,600 deg. ceramic fiber blanket and an inner 3/4" liner of Kastolite 30. Also, the ends of your burners are exposed to the heat and too far inside the forge. The flare needs to be protected from radiant heat or a ceramic burner head used. Quote Link to comment Share on other sites More sharing options...
Frosty Posted August 2 Share Posted August 2 From the look those aren't Morgan Ceramics, K-26 IFBs so I'm frankly surprised they've lasted this long. Even K-26 don't like being directly exposed to propane flames from well tuned burners. Our club held a burner / forge clinic some time ago and made something like 35 each. 4.5" x 4.5" x 9" chamber, 185 cu/in no weld burners driven by single 1/2" T burner. The flame face was kiln washed with Plistex/ zirconium silicate mix. Each one cost about $100 including regulator, and hose. Bear in mind the club bought the materials enjoying discounts for quantity and being a not for profit organization. I'd add at least 50% as an individual, probably more considering inflation. They are holding up very well, nobody on the club FB group has said anything about needing to rebuild one and several of the users are professional bladesmiths who make pattern welded billets and folded blades. Pic below. The forge shown was finished maybe half an hour earlier and this is less than 5 minutes after lighting. That said my own experience shows IFB forges work nicely. K-26 are rated for sustained max working temp of 2,600f and have a safety margin the company won't tell you but melting steel in them is easy. The reason the old type IFBs break up is because they can't take the rapid expansion and contraction of our forges. NO MORTAR, EVER! Mortars have a different COE than whatever fire brick you use, especially IFB and enhance IFB's tendency to break up with the rapid thermal cycling of these propane burning machines. They really need some room to move against each other, the blow forges are loosely bolted together, they rattle until hot. The T burners driving the below forges are only about 1/4" into the IFB and as far out of the forge as possible and maintain effectiveness. Pulling them farther back causes flame to escape around them. In general we used 1/2" pipe thread protectors for a "flare". I dip or paint the internal threads of mine with plistex to help preserve them from the extreme heat and corrosive nature of propane flame. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Archie Otteson Posted August 2 Author Share Posted August 2 Thanks for the advice. There is a source for any forge material needed about 30 minutes away from my house. I will keep this one working with new brick and start planning the wool lined forge. Quote Link to comment Share on other sites More sharing options...
Archie Otteson Posted August 2 Author Share Posted August 2 Frosty, that forge design looks even better. Thanks for the help. Quote Link to comment Share on other sites More sharing options...
Frosty Posted August 3 Share Posted August 3 You're welcome, it's my pleasure. Originally I wanted to make them so a person could put them end to end for long stock, say twisting fence pickets but I wasn't the only one designing them. They did turn out really nice. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Archie Otteson Posted August 3 Author Share Posted August 3 Another question..... There's a U-tube video where a guy put moveable plates on the sides of the pipe T intake. He claims it's an improvement to restrict/regulate air supply drawn into the forge. I've only seen one application of this on a T-burner. Useful or hype? Quote Link to comment Share on other sites More sharing options...
Frosty Posted August 3 Share Posted August 3 Lots of guys put choke plates on T burners. What it indicates is someone who doesn't know how they work and can't follow directions. I spent quite a bit of time trying to make my T burner plans as simple as possible, even had help from an editor. If you built it correctly it has a VERY FLAT induction curve so you tune it by adjusting the jet length, the closer to the mixing tube throat the richer the flame from minimum to maximum stable psi. The farther back from the mixing tube throat the jet is the more combustion air is induced from min to max psi. Too many people who don't actually know how induction machines work use too small a jet diameter, the propane jet being a mig contact tip, and put it too deep in the T so it can't possibly induce enough combustion air for the propane injected. It MUST inject at a way too high pressure to supply enough and induction rates are geometric, not linear. Meaning 2x the pressure results in 4x the propane injected AND 4x the air induced, which means there is NO change in the fuel air ratio so the burner is too lean no matter the psi. Unfortunately it is a high psi high velocity machine and blows what flame it makes right through the forge into your breathable atmosphere in the shop. If you have to put a choke of any kind on a T burner you screwed up the build. PERIOD DOT. Most can be corrected but NOT by hanging more . . . stuff on it. Forget Youtube the vast majority of people posting have no clue how virtually anything they're showing works. Worse way too many show downright dangerous devices, practices, methods, etc. Sorry to get off on a rant but I hate seeing such a simple, easy to build burner presented as a how to video. Frankly I'd like to be able to past labels on some of them ranging from, 'How NOT to build x", to "DANGEROUSLY BAD HOW NOT TO!." Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Archie Otteson Posted August 3 Author Share Posted August 3 You guys are great. Thank you all! Quote Link to comment Share on other sites More sharing options...
jcornell Posted August 18 Share Posted August 18 Frosty, Do you perchance have a blueprint for this no-weld IFB forge? Quote Link to comment Share on other sites More sharing options...
Frosty Posted August 22 Share Posted August 22 Blue print? We don't use no steengkeeng blue prints! I didn't design the things, the club got together and a number of guys started stacking and imagining things and DANG if it didn't work this time. You should be able to count bricks and see how they're arrange in the pics and that's about all there is to them. I don't have one or I'd make a dimensioned sketch and post it but they all went to club members at the end of the build day. If you have questions or problems, give me a shout. I'll be more than happy to help. These are all made from Morgan Ceramics, K-26 insulating fire bricks. That's about the most critical thing about them old IFBs tend to crumble where K-26 work a treat. Morgan makes a higher rated IFB but they're more $. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
BsnNFrnt Posted August 29 Share Posted August 29 Based on what I am seeing from your forge build you have the patience to reinforce your forge with coated ceramic wool and/or castable refractory. For instance, I had the same problem with my first forge. Prior to my exposure to the teachings on this site - I modified my forge: step 1 - disassemble and score interior fire brick with circular saw and masonry blade step 2- re assemble with the same style of mortar in the same shape step 3- turn forge on side and pour in 1” layer of castable refractory on each wall allowing gravity to help adhere refeactory to brick. repeat 4 times I lost substantial internal capacity but it held heat way better step 4 - even though it was not sealed or treated properly it lasted 6 months after this debacle I started reading this site and have only built 1 forge since. step 5 - Build a ribbon burner with 3” thick refractory walls and run it hot as you want for years Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.