Levi Prince Posted July 8, 2020 Share Posted July 8, 2020 Hi, I'm new to forging and just building my first propane forge. It's a big one- about 2500 cubic inches. I made venturi style burners (3 of them), figuring that would work. Problem is, outide the forge they work pretty great, but once installed the flame is very weak and often just oxidizing, even though I can control the amount of air going in. I'll post videos, but here is the info anyways. The burner construction is as follows. Straight from the tank there is a high pressure regulator with a hose that leads into 2 tees in order to split the assembly into 3 branches. At this point the pipes are 3/8, but they lead through 90 degree elbows and reduce into 1/4 to go into the burners themselves. There are ball valves on all three. I threaded the pipe nipples and put it through a bracket which is welded to the reducer on the top of the burner. A disc is threaded onto the pipe so that it can move up and down on top of the reducer in order to control the amount of air going in. At the end of the pipe there is a cap with a 0.035 MIG tip for a jet nozzle. The reducers themselves are 1-1/4 to 3/4, the burner shafts are 3/4 by 8. Currently they are just being held in the forge by 3 pipes welded to the body that the burners just sit in, I'm wondering if I need to make the pipes bigger and just use retention screws so that there is extra space around the burner for air getting into the forge. Here are the videos of the burners outside of the forge, as well as inside. In the videos of the burners installed in the forge, I am using a hair dryer to blow more air into the forge and you can see the flames immediately get better. Any help would be appreciated. Do I need to change to forced air? https://drive.google.com/file/d/19G5r9ooaupDswwOTEb7V86BOxJCLwvaf/view?usp=sharing https://drive.google.com/file/d/1I3u6BKHZkke4ReYdSmcobE7I1L23mcue/view?usp=sharing https://drive.google.com/file/d/1_NdbDASkVa0yWP81iZXV_j_EZYY8fb-W/view?usp=sharing https://drive.google.com/file/d/1d_ENhJzxfnhyX8lo3VjfN7li14zRJ0JR/view?usp=sharing Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 8, 2020 Share Posted July 8, 2020 Welcome aboard Levi, glad to have you. If you'll put your general location in the header you might discover how many members live within visiting distance. Your description is not clear enough to be of much help and the videos are nearly useless. Have you asked the person who's plans you followed for help? Didn't follow plans did you? A couple minor points, the length of a 3/4" naturally aspirated burner mixing tube is NOT 8". The 8:1 ratio that so many MANY people don't understand does not mean 8". It means you multiply 3/4" x 8. I don't know of anybody using a 0.035 mig tip in a 3/4" linear burner. I strongly suggest you pick ONE proven set of plans and FOLLOW them without trying to improve them. I'd like to help. If you post some STILL PICS, videos aren't much use, we'll see what we can do. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Levi Prince Posted July 8, 2020 Author Share Posted July 8, 2020 Thanks for the info! Ill try to get pics tomorrow. Do you think there's any way I could fix this, or do I have to start over? Also, is there a specific design you think I should follow? It's a much bigger forge than any I've seen on other people's plans, so It would need to be a design that would work with multiple burners. Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 8, 2020 Share Posted July 8, 2020 You're welcome Levi, it's my pleasure. I can't tell if your burners can be salvaged without some pics. Why in the world do you want such a huge forge? Are you building it for a commercial operation to keep 4-6 blacksmiths in hot steel? If you built properly tuned 3/4" linear burners you'll need probably 7 or 8 to heat that large a volume. I'll bet that much propane draw will freeze a 20 lb tank in under half an hour, 45 minutes max. The few times I've had all four 3/4" T burners going on my over sized shop forge the 100lb. tank started freezing the condensation on the outside in about an hour. We didn't keep it going long enough to start freezing the propane but we could've powered a heck of a beer cooler with it. What would I recommend for burner plans? Do you have a drill press? How good are your shop skills? Be honest now I've had glimpses of your work. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Levi Prince Posted July 8, 2020 Author Share Posted July 8, 2020 I do have a drill press but it tends to wander quite a bit so some of my holes end up crooked. I also have a mig welder as well as most conventional tools. The forge is pretty big, 9” diameter by 35 and I’m running it off a 100lb tank. The forge is actually made out of a 100lb tank too. but if you want to show me some plans I could tell you whether it would work for me or not. Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 8, 2020 Share Posted July 8, 2020 Wander, does the spindle have lateral lash? Can you move the chuck sideways? Lash is sideways movement in a shaft that should only turn. If there is no lash it's either drill bit that need sharpening or you need to work on your technique. Again, what do you think you're going to need to heat? You aren't going to forge 200lb. anchors or similar are you? Seriously you can only forge about 6" of steel at a time, heating more only damages the steel. It decarburizes the surface and causes large crystal growth, commonly called Grain Growth. Those are BAD things. You're just starting out, how about making something you can afford to make and use? You can always make a larger forge if you need one down the road. Have you priced materials to build your proposed forge? A couple quick calcs on the trusty old calculator says you're looking at buying about 15 sq' of 1" 8lb. Kaowool or equivalent ceramic wool refractory blanket and maybe 20lbs. or more of Kastolite 30 or equivalent water setting hard refractory. Oh heck just buy a sack of Kastolite 30! Plus whatever kiln wash you wish to apply if any. I don't know about prices where you live but I'm thinking $200 +/- to line the forge at my prices and I get a heck of a deal. I don't even know what a good kiln wash would cost, probably another $50 or more. Now lets think about building a burner. I can build a 3/4" T burner for about $12. not counting the tubing and fittings to connect to a manifold. From the manifold to the tank costs the same, 1 burner or more up to the carrying capacity of the regulator. Mc Master Carr says a 3/4" x 2" bell reducer is $16 and change. I don't buy that price but maybe the rice has gone way up I haven't checked recently. Your design has two bell reducers per burner but lets say one on the T as add another $10 to my guesstimate making a $22. Burner and you will need seven or eight to bring that monster to a high working temp, low welding temp. So, what $160 - $175 for burners. We can figure there is another $10+ per burner for brass fittings to make up to copper tubing. You do NOT even want to think about what it'd cost for rubber propane hose! Do you see where I'm going here? Can you afford to spend maybe a thousand bucks on a forge that'll go through $100 worth of propane in an 8 hr day? Can you afford that? How about this instead? This is a no weld, clamp together 180 cu" forge, one of many we built in a club forge build workshop. Total cost to the guys was $90 with $20 going to the club. I took this pic about 5 minutes after lighting the forge. That 1/2" T burner will run at this temp for at least 20 hrs on a 20 lb. tank of propane. The chamber is 4.5" x 4.5" x 9" and club members are making knives, hammers, tongs, etc. A horse show will fit if you lean it up against the side. There is a pass through door on the far side so you can heat long stock in the middle or heat long sections by passing the stock back and forth through the forge. Weld in one of these? Oh baby you sure can! Hmmm? Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Levi Prince Posted July 8, 2020 Author Share Posted July 8, 2020 Well I don't need to price up the forge, Already built it haha. It's a 100lb propane tank lined with 2" of kaowool and half an inch of 2800 castable refractory (I can't buy kastolite or any of the good ones where I live, and the shipping is nuts). I would like to not have to start over from scratch, seeing as how I've spent a few hundred bucks on this forge already. I was looking at making swords and large axes so that was the reason for the size of the forge, but If I really don't need to make it that big, could I just make a refractory plug to put in the middle to "shorten the forge" when I don't need the full length? Also, I suppose I could cut it in half and just have two 18" long forges so I have a backup Also, when you say 3/4" burner are you meaning a true 3/4 of an inch because I'm using "3/4" inch pipe but it's actually a lot bigger than that. When I was blowing air through the forge with a hairdryer and only running one burner, it got a 5 inch section of flat stock up to a dull orange in about 3 minutes from cold. But if I do need to make new burners, could you supply a parts list for those brass fittings and whatever size Tee I need? Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 8, 2020 Share Posted July 8, 2020 I'm sorry that this is going to seem like dogpiling; but how do you use that forge to only heat 6" of sword blade? You only want to heat as much as you can effectively work before it cools as heating more DEGRADES the metal. Building a forge that ruins a sword is not a suggested sword forging method! The Vikings and Franks forged pattern welded swords in forges with about a 6" hot spot in them and did so for centuries. It would have been trivial to make longer forges back then as they were basically "hole in the ground" type forges. Yet they didn't---good archaeological evidence to that effect. The only time you need to heat the whole length at once is for hardening. Which can be done in a smaller forge by passing the blade back and forth through the hot spot---or I have been known to build a trench forge just for that step. No need to buy a dump truck and use it as your daily driver just because a couple of times a year you need to buy a load of gravel! The cost of running that size of forge when you don't need it would pay for a bunch of more forges of differing sizes. I'd save that forge for heat treating and build a working forge that is MUCH smaller and efficient to use! I must admit to being perplexed about what I saw as "I don't know what I'm doing; so send me the plans and I'll tell you if they will work". When the ask was "Tell us what you want to do so people with experience doing it can tell you what you need to do it." And yes a number of people on here have made swords before; you may have read some of their published books on blade smithing! Note that once you get good at sword forging you may want to tool up: a powerhammer allows you to work longer sections at a time---especially one that's hitting over 200 blows a minute! So storing that large forge for heat treat and power forging is an option. Hopefully your throughput will ramp up to where the cost of running it is paid for. I guess I really lucked out; I had been forging with solid fuel around 2 decades before I built my first gasser. I also did it as part of a gas forge building workshop put on by an ABANA affiliate and so designed by folks with experience using them. I really switched to propane as my primary fuel when I moved 1500 miles from my *good* smithing coal source; but only 6 miles from a good propane source...(Also fire regs get really tight around here when the winds are 25-50 mph and the temps over 105 degF and the humidity is in single digits! Propane forges will be allowed at times when "open fires" are strictly banned.) Quote Link to comment Share on other sites More sharing options...
Levi Prince Posted July 8, 2020 Author Share Posted July 8, 2020 Thanks a lot for the info, I didn't know you could only heat so small an area. I really do want this to work without having to make an entirely new forge, so would it work better just to cut it in half? And here are pictures of my burners, so if they are salvageable please let me know, if not I'll make those tee burners if those will work a lot better. Im sorry if I sound like I'm ignoring your guys advice, it's just that I've spent a bit of money on this so far and I don't want that to be wasted, so if i can make my existing forge smaller and just remake the burners that would be best. Believe it or not, where I live in canada, I can't get any of the popular castable refractories unless I pay a small fortune on shipping, and the best I can get here is 2800 degree stuff from a pottery place that's 80 bucks for a 50 pound bag! So that's why I want to salvage this forge. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 8, 2020 Share Posted July 8, 2020 First of all the money is not wasted as you learned an important part of life: Research BEFORE you Build! If you didn't know about heating only as much as you could work; you didn't know enough about sword forging to be building a forge for swords! Even cut in half the volume on that forge will cost a lot to heat. Does spending $400 extra in fuel to save $200 in forge building supplies actually save you money? Now what I advise people is to start by forging knives; this will teach you about handling blade worthy alloys: forging temps, hammer control, how different alloys work under the hammer, etc. And since the turn around time on a knifeblade can be weeks shorter than a sword blade you can make your learning mistakes faster and cheaper and learn from them. In particular I start students off by taking a coil spring, (the fewer miles the better!) and cutting it on a diameter to get a dozen to a score of "(" pieces all of the same alloy to practice on. (Some people like to practice on mild---but you need to practice how High C is worked and heat treated!---Expect to break most of the blades you forge from the leaf spring to learn how forging temps and heat treating affect the steel.) As an added bonus coil springs are often close if not the same alloy as leaf springs and that makes a decent sword alloy! Once you get good at forging and grinding knives; go on to large knives. When you get good at them think about doing swords and remember that swords are NOT just large knives. Their size means that you need to start factoring in things like weight and harmonic nodes. (Note that for about 1000 years in Western Europe a battle sword was about 2.5 pounds; just over a kilo; strange but that is a good weight for a Japanese Katana too!) If you want to win car races would you want to learn to drive in a race car in formula 1 races? Or would you learn the basics first and progress to racing? And; Welcome to the Madness! Quote Link to comment Share on other sites More sharing options...
Levi Prince Posted July 8, 2020 Author Share Posted July 8, 2020 Ok....would it work to make a new forge out of a 20 pound propane tank? Line it with kaowool and refractory. I don't know if that would be closer to the right volume. I saw a video of a guy making one like that and it looked quite good, except he just had exposed kaowool, if I made that design obviously I would cover that with castable. If that would be the right volume, what should I do for burners, the design this guy uses in the video, or would a tee burner work better. The only problem with the tee burner is that you can't regulate the air, but maybe that doesn't matter as much as I think it does. Also, if you had a 500$, 200 pound cylinder of concrete and wool and steel, what would you do with it? It seems a shame to throw it out, especially when it's such a good insulator. Any uses I could have for it? Here is the link to the video: Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 8, 2020 Share Posted July 8, 2020 Have you seen the plans for a 20# propane tank forge on Wayne Coe's site? Place in a corner until needed? Quote Link to comment Share on other sites More sharing options...
Levi Prince Posted July 8, 2020 Author Share Posted July 8, 2020 Yeah I guess...Anyhow if the 20lb will work, which burners should I make? I'd prefer to make them because they are quite expensive to buy, and I know plenty of people make great burners on their own. Wayne doesn't make the burners on his site, they are bought from companies. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 8, 2020 Share Posted July 8, 2020 I'll leave that up to the Burner gurus; I can say I just installed a set of T burners into my 20 year old forge. (Shell is 20 year old the liner gets redone as needed). Still tuning them but currently they are running rich and HOT! Had to turn down my regulator till almost zilch to keep the forge at a reasonable temp... I'm a scrounger and so stockpile useful stuff as I find it; so my propane hose was from a blisterpack one made to run a heater, Cut it off their end and put the end I needed. Bought it at a garage sale, never used, for US$5. Got a high pressure regulator once from a turkey fryer for $2 or $3, fellow bringing it to the fleamarket had accidentally let it drag over the edge of the trailer and wore the brass fitting down. I replaced it with an identical fitting from a propane grill someone had tossed in the alleyway. Shoot I even once was given kaowool from laboratory furnaces that went through my local scrapyard. I did buy the small amounts of kastolite I needed from Wayne at Quad-State; but I have found a refractory source just an hour and a half north of me now. Cost is always a balance between Money and time and ingenuity! I find He Party Balloon tanks at the scrapyard and have a handful at my smithy to give away to people who talk about *BUYING* a propane tank to make a forge out of. It's a different mindset to me. My grandfather, in his mid 90's, tells folks I'm the only grandkid he thinks could weather another great depression. Quote Link to comment Share on other sites More sharing options...
Levi Prince Posted July 8, 2020 Author Share Posted July 8, 2020 Well I do love to scavenge! I already have some 20lb tanks, and the 100lb tanks I got full for free from a guy on kijiji (like craigslist but in canada). Currently all my high carbon steel is scavenged from car parts like bearings, leaf springs and coil springs. I guess I'll give the tee burners a go, my pressure regulator is good from 0-60 psi so I do have alot to work with there and I could probably use a ball valve for the gas volume to just adjust that to the set amount of air going in. Are there any actual plans for the frosty tee burner? because I'd hate to mess this up again. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 8, 2020 Share Posted July 8, 2020 What did you find when you did a browser search of: Frosty T burner plans site:iforgeiron.com ? I get 1400+ hits and good ones from the very start! Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 8, 2020 Share Posted July 8, 2020 Levi, forget about PSI it doesn't matter that much. I've emailed you the plans. It should NOT be necessary to do a web search to find the T burner plans and have to wade through 1,400+ posts to find ONE post with the PDF file with the plans and tuning instructions! They should at least be linked in a sticky. Anybody know where the stickies are or do we have to search for them too? Sorry guys but I'm STEAMED! We've been telling new guys to do some research BEFORE asking asking questions and this morning I discovered researching almost anything in the Iforge subjects is like finding something in an encyclopedia that's a box of mixed single pages. No wonder new guys are asking questions we've answered hundreds of times. Iforge just tosses our answers in a folder and forgets about them! There aren't even gas forge subfora beyond: insulation&refractories, ribbon burners, and ONE instructional video! If you're looking for something sort of specific you'll have to dig through 87 PAGES and read the posts. It's small wonder I get sometimes half a dozen guys a week asking me how to make a T burner, the plans were tossed in a box by IFI. Frosty Quote Link to comment Share on other sites More sharing options...
Irondragon Forge ClayWorks Posted July 9, 2020 Share Posted July 9, 2020 Your T Burner instructions is a sticky, right under Burners 101. Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 10, 2020 Share Posted July 10, 2020 Yes it is. I want to offer the IFI membership my apologies for going off the rails. Sometimes things get to me WAY out of proportion to reality. My bad,, no excuse. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 10, 2020 Share Posted July 10, 2020 Probably the heat; you need to keep your cool! I hope to get a little time in the smithy between 5 am and 9 am this weekend and then go estivate! Quote Link to comment Share on other sites More sharing options...
Levi Prince Posted July 13, 2020 Author Share Posted July 13, 2020 Ok so I’ve made a small forge now, with Frosty’s t burners, an they work great outside the forge, but inside they sputter a lot and are very weak. Again, if I blow into the forge it gets much hotter, which leads me to believe it’s the same problem as before. This is really frustrating so if anybody has a straightforward answer I would appreciate it. I am just about out of money so I can’t build a whole new system. Would it fix the problem if I plugged one end of the t and attached a small blower at the other to increase the air getting in? Quote Link to comment Share on other sites More sharing options...
Latticino Posted July 13, 2020 Share Posted July 13, 2020 Did you follow his design exactly, or did you just use whatever length 3/4" pipe nipple you had around with a 3/4" x 3/4" x 3/4" TEE fitting (because it was difficult to find the correct reducing fitting), and put a pipe reducer on the other end as a flare like so many folks do? Frosty's burners are pretty easy to construct (by design), but they do need to have the mig tip orifice correctly positioned. Part of that positioning is drilling and tapping the back of the TEE as accurately as possible so the tip is centered and inline with the center pipe of the TEE. The other part is locating it in the correct place in line with the mixing tube so it induces the correct amount of air. This latter is the fine tuning that needs to be done for these homebuilt burners, and one of the key challenges for the design. Frosty can likely help you here better than any of the rest of us. Blown burners are much easier to tune, IMHO, and what I use myself. You likely could do what you described to make your burner into a blown one, but you might not get adequate mixing with that configuration. Just remember that if you start experimenting with a blown burner you need to be very cautious with your lighting and shutting off routines. Quote Link to comment Share on other sites More sharing options...
Levi Prince Posted July 13, 2020 Author Share Posted July 13, 2020 I followed his plan and used a 1” to 3/4” reducing tee, with a 6” pipe nipple and a merchants coupling nozzle. I honestly don’t know what to do. Quote Link to comment Share on other sites More sharing options...
Latticino Posted July 13, 2020 Share Posted July 13, 2020 Take a photo of the flame both inside and outside the forge as well as the . If you ask very nicely Frosty will most likely help you with tuning properly. Also shots of the entire gas train will help, to be sure you are using the right regulator setup. Good luck. Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 13, 2020 Share Posted July 13, 2020 Levi: Tune your burners IN THE FORGE. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
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