Broomhead Posted January 4, 2014 Share Posted January 4, 2014 I have successfully built one of Frosty's 'T' burners going by the plans in >this thread. I used a 3/4" tee, 3/4"x6" nipple and everything else that the poster used on his. The only deviation I made was that I used a 3/4"x1" bell reducer as a flare. This is my regulator, I have yet to get a gauge so I can't really tell you what pressure it's running at. The burner will chuff a little at lower pressures, but runs like a jet engine when turned up to where its smooth. I used a piece of 6" diameter stove pipe as a buffer to cut down on the burner's sensitivity to wind. All-in-all I spent about 50 bucks, including the regulator, since I had to buy new parts. I already had a few of the tools, like the 1/4-28 tap and #3 bit, but I had to hunt down the 1/8" NPT pipe tap. Here are a few pics, minus the wind buffer. Click this one for a short dragon's breath video. Now for a quick question, I made one a bit bigger, using 1" diameter parts instead of 3/4" ones, with a 1"x1 1/4" bell reducer flare. The only problem is that the flame burns inside of the tube, starting at the mig tip instead of starting in the flare. What do I need to do differently for this larger burner to run right? What things need to be tuned differently? Does the mig tip need to be longer? Should I cover or partially cover one of the tee openings on the side? Should I use a shorter nipple? The OAL of the big burner is only 1/2" longer than the smaller one. Thank in advance for all the wisdom. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted January 4, 2014 Share Posted January 4, 2014 Remember that the differences are based on the area and volume so your tube area is now .785 vs .442 Big difference! the jet is not pushing the gas down the tube fast enough to exceed the flame propagation speed and so it burns back until the two speeds match. A narrower tube or higher pressures *may* help but what you probably need to do it to build one to the specs that work! If you were working on your car engine would you use a piston 1/4" wider than the old one and expect it to work; or would you expect to have to redo the entire engine and fuel supply to get it working again? Quote Link to comment Share on other sites More sharing options...
Broomhead Posted January 4, 2014 Author Share Posted January 4, 2014 Thank you Mr Powers. I thought I had read where people had had success with slightly larger dimensions using the same general setup by simply tweaking the various tunable aspects of the burner. Perhaps I'm mistaken. I did build a successful one using a 3/4"x6" pipe nipple, a 3/4" tee, and a 3/4"x1" bell reducer. It doesn't burn back in the tube at lower pressures, so I was unsure what was happening when I tried the larger tube. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted January 5, 2014 Share Posted January 5, 2014 the area is 78% larger not quite slightly You might look at larger burner designs and see what they change from your 3/4" one. For my forge I just made 2 3/4" burners, makes for a more even heat in the forge, parts are cheaper/easier to find, etc. Quote Link to comment Share on other sites More sharing options...
Broomhead Posted February 9, 2014 Author Share Posted February 9, 2014 I need some help tuning this baby, if y'all wouldn't mind. I keep getting what I guess you'd call flame-outs. It's not so much chuffing as it is the flame goes completely out and then the residual heat of the forge reignites the propane. Changing the pressure has no effect on the flame-outs, they happen from 5-25psi. Here's a video of what I'm talking about. In it you can see the shape of the flame and there is a shot of the dragon's breath at the very end. I edited out the longer periods when it was running normally, but it is from one continuous recording. During the first roughly half of the video the pressure is at 15psi, the second half (with the RR spike in the forge) I dropped it down to 8psi. What do I need to do to prevent these flame-outs? What should I change to tune this for best results/efficiency? Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 9, 2014 Share Posted February 9, 2014 I usually recommend against using a bell reducer for the flare but your 3/4" has a nice flame. No sense fixing it if it ain't broke. The 1" needs a 0.045" mig tip for the jet and the tube length should be 8-9 x the diameter. Everything else sounds within tuning range. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Broomhead Posted February 9, 2014 Author Share Posted February 9, 2014 Gotcha. Buuuut...What about the flame-outs? I forgot to mention that the ambient temp was about 28*. Could that contribute to the flame-outs? I know the cold temps have an effect on how long the tank can maintain it's pressure. However, the flame-outs happen regardless of the pressure. Quote Link to comment Share on other sites More sharing options...
Dodge Posted February 9, 2014 Share Posted February 9, 2014 I am running a 1" T burner. My tube is 9" IIRC (could be 8") But anyway, It runs great. I don't use a flare but rather the inlet port in the forge shell is (theoretically) a 12:1 taper that is molded in the wool and refractory. I didn't use a .045" as Frosty suggests above but rather a .035" tip drilled to #59 or #60 (.041" or .040") I also cut flares in the openings of the T; 1/4" or 3/8" X 45(ish)º, but I don't know how much this adds or subtracts from performance as I usually choke the burner quite a bit closing a large amount of the opening. Bottom line is, Broomhead, all other things being equal (loose term), I believe most of your issues would be resolved by a longer burner tube. Might not even need the wind shield. I have only worked with 3/4" and 1" but these T-burners of Frosty's seem to be very forgiving as long as the basic dimension ratio is maintained. Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 10, 2014 Share Posted February 10, 2014 A longer tube in the 8-9" range and the 0.045" mig tip will make it run better. The one thing I did see in the video when you were shooting from the side. The dragon's breath showed yellow flames just before it chuffed out and the cause looked to be a breeze blowing the exhaust gasses back over the forge to the burner intake choking it out of oxygen. Something to break the breeze or turn the forge so it can't blow the exhaust into the intake. A longer tube and bigger jet will let you run low psi with better stability. The flame will be tighter and a little more robust without the bell reducer. Try a thread protector or spend the extra and buy a coupler. The induction will be stronger so the flame will be a little leaner and cleaner. The dragon's breath won't be quite so orange and the forge should get hotter. Dodge: You chased a mig tip to 0.040" or so and you're having to choke the intakes. Try a 0.045" mig tip, it'll put more gas into the stream and you won't need to choke it. That will put more gas and air in the fire at the same time and that means more BTUs per second. Hotter is better, you can always turn it down if it's too hot you know. <wink> Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Broomhead Posted February 10, 2014 Author Share Posted February 10, 2014 Thanks for the info Frosty. I picked up a 3/4"x8" nipple and I'm trying to hunt down a .045" mig tip. There's a wielding supply place about 15mins away that I'll call up. I already have a coupler that I tried before the bell reducer that didn't stay lit, I'm guessing it just needs the bigger mig tip to work. As soon as I track down that mig tip I'll let you know how things workout. Quote Link to comment Share on other sites More sharing options...
WayneCoeArtistBlacksmith Posted February 11, 2014 Share Posted February 11, 2014 When you get the mig tip be sure and get a Tapered tip. I have had students come to me with a burner that they had built and that would not burn well. All we did was replace a standard tip with a T tip and it worked perfectly. Quote Link to comment Share on other sites More sharing options...
Broomhead Posted February 12, 2014 Author Share Posted February 12, 2014 Ok, just to be clear, I'm talking about the 3/4" burner in all of this, the flame-outs, etc. I haven't rebuilt the 1" one yet. I found .045 tapered mig tips (15 xxxxxxxx bucks for a 10 pack). I plugged in the .045 mig tip, attached the 3/4x8" nipple with a 3/4" coupler. It wouldn't stay lit at any pressure. I couldn't get the bell reducer off of the 6" nipple to try it on the 8" nipple. I put the 6" nipple with bell reducer back on with the .045 mig tip and had a huge flame, over a foot long. Stuck it in the forge and had a huge dragon's breath. At 8psi, The forge heated up faster than I could pull my phone out to take a picture/video of the flame, but I did record the dragon's breath. I'll post it as soon as I get it edited. I think Frosty is right in that I'm getting exhaust gasses sucked back into the burner, I'll turn the forge tomorrow and try that. I had a couple flame-outs when there was a breeze. I stuck the stovepipe over the burner and it smoothed out. Quote Link to comment Share on other sites More sharing options...
Dodge Posted February 12, 2014 Share Posted February 12, 2014 Thanks Frosty. Might give it a try. I just used the drilled .035s as that's what I had on hand. Guess I could drill it out more. After all, it came from the same source as the tip I use in my gun burner. I just drilled the .035" tip to .052" or #55. :) Quote Link to comment Share on other sites More sharing options...
Broomhead Posted February 12, 2014 Author Share Posted February 12, 2014 Here is the video of the dragon's breath with the 6" nipple with bell reducer and a .045" tapered mig tip. Much larger and much bluer. I tried getting a shot of the flame but it was just too hot already. Quote Link to comment Share on other sites More sharing options...
Dodge Posted February 12, 2014 Share Posted February 12, 2014 This is what I love about this place. After all these years, I learn something new with each visit. I forge outside and often suffer from the inherent issues with wind and atmospheric burners. After seeing it in operation, I think that stove pipe idea would be great to try in my forge area!! Scott Quote Link to comment Share on other sites More sharing options...
Broomhead Posted February 12, 2014 Author Share Posted February 12, 2014 Ok, so the 8" nipple (I love typing nipple) works with a bell reducer attached, but not with a straight coupler. I have a nice big flame, but it's difficult to see the shape of it in the daylight, along with the dragon's breath. I'll have to check it out and record it tonight. So, the 8" nipple and the 6" nipple both work with a bell reducer and the .045" mig tip. The 6" nipple heated up the forge really fast at ~8psi, but it was sucking in the exhaust gasses. Tonight, I'll also try turning the forge to see if I can get the gasses to blow a different direction. The 8" nipple also heated it up quickly. However, there wasn't a breeze to tell if it was sucking up the gasses, though the T is higher up so it may not just for that reason. I'm worried that using the stovepipe will trap too much heat and burn up my pressure gauge, which stays cool to the touch without the stovepipe. I think, if I end up using it, I'll shorten it just enough to keep the gauge in the open air. I'll be able to see it then also, lol. I'm torn now, I don't know whether to go with the 6" nipple or the 8" nipple. The 6" nipple would be cheaper as I can still return the 8" nipple, coupler, and bell reducer. I'm leaning towards the 6" nipple, but I'll wait and see what happens tonight when I try to turn the forge and record the 8" nipple's (can you tell I like that word?) flame and dragon's breath. Quote Link to comment Share on other sites More sharing options...
WayneCoeArtistBlacksmith Posted February 13, 2014 Share Posted February 13, 2014 I have my pressure gage on the regulator which is on the propane tank several feet away from the burners and forge. The Frosty T burners that I have seen always seem to have the T sitting horizontally. I wonder if turning the burner so that the T is vertical would have an effect on the breeze problem. Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 13, 2014 Share Posted February 13, 2014 Broomhead: I put 0.035" mig tips in 3/4" burners and 0.045" mig tips in 1" burners. However one of the guys here is getting good results with 0.045" mig tips in his 3/4" burners so use what works. There IS a lot of dragons breath coming out of your forge but it's blue and she looks hot. I'm not sure what to say about that. 8" nipples are about right for 1" burners and a bit much for 3/4" burners. EG. 8 - 9 x 3/4" = 6" - 6.75". You're a whole lot closer to right on the money with a 6" nipple. I can see I made the basic ratio rules of thumb too confusing, a little arithmetic and you can make any size burner following them. Put your gauge at the tank, it'll live a LOT longer. they have rubber diaphrams in them that don't like heat. I'll be giving your stove pipe breeze shield a try, it's so much better than the lash up I did. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 13, 2014 Share Posted February 13, 2014 I have my pressure gage on the regulator which is on the propane tank several feet away from the burners and forge. The Frosty T burners that I have seen always seem to have the T sitting horizontally. I wonder if turning the burner so that the T is vertical would have an effect on the breeze problem. I'm not clear on the idea Wayne. Do you mean have the burner mounted on the forge horizontally or put the "T" on the tube by one leg? As in a "Sidearm"? I've thought about mounting my burners horizontally but just haven't tried it. We did mount a 1" "T" in a Whisper Momma through the end and it worked really well it didn't have end doors. I think a horizontal mount may be a good way to avoid the exhaust plume and sure worth giving it a try. I just don't see it doing much for breezes though. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
WayneCoeArtistBlacksmith Posted February 13, 2014 Share Posted February 13, 2014 Sorry Frosty, I meant if the burner was mounted tangently (more or less level with the flame coming in across the top of the forge and swirling around the inside of the forge for more even heating and less hot spot) rotating the burner 90 degrees so that the two legs are up and down so that a breeze coming across the burner would not be directed directly into the burner. I had no intent of modifying your burner. Also, with a burner mounted tangently there is less problem with the chimney effect of heat "chimneying" up the burner and deteriorating the burner. I also always close the baffles on my burners when I turn the forge off to further limit this chimneying or drafting of heat into the burner. Quote Link to comment Share on other sites More sharing options...
Broomhead Posted February 13, 2014 Author Share Posted February 13, 2014 Well, turning the forge didn't help the burner with the 6" nipple, it was still sucking exhaust gasses causing it to flame-out, even with the stovepipe. I guess it's just too short/close to the mouth of the forge for my setup. The 8" nipple ran like a champ though, a nice rich blue dragon's breath, a strong, steady flame, and the forge heated up amazingly fast at just 8psi. Again, it heated faster than I could get the flame recorded. The 6" nipple's dragon's breath was much more yellow as well, so it was running too lean, even when I covered one of the T's openings. I kept the .045" mig tip on for both runs. The 8" nipple's dragon's breath is in the video clip below. I am working on moving my gauge away from the burner, but it's the best I can do right now. I'll have to wait on some money to pay for the parts to move it, my blacksmithing funds are tapped out right now. Fwiw, it stays cool to the touch where it's at, as does everything between the burner tube and the hose. I am in the planning/acquiring stages of building a new, round forge body. I plan on mounting the burner(s) tangentially as I have heard/read that the heat is more even and without hotspots. Now...I just need to exchange tanks and get back to beating some hot metal. Thank you everyone for your help. If you have any further tips/suggestions, please post them and thanks in advance. Quote Link to comment Share on other sites More sharing options...
EricJergensen Posted February 13, 2014 Share Posted February 13, 2014 Consider using the stove pipe to get the exhaust gases away instead. Quote Link to comment Share on other sites More sharing options...
Frosty Posted February 14, 2014 Share Posted February 14, 2014 Eric has a good point, using the stove pipe or similar to direct the dragon's breath and exhaust gasses away from the burner works well. It's how I do it on my forge, I only have two pieces of split brick sticking out over the opening to deflect the flame from going straight up. It works well in most situations, Ionly dig out the wind screen when it's breezy. Yellow flame means rich and blue means anything from neutral (stoichiometric) to lean. It takes time and experience to tell what a blue flame is telling you. Just remember orange and yellow are rich, not enough oxy. to consume all the fuel. A LITTLE rich is better than a little lean, a lean fire will oxidize the steel in the fire. Hot steel will always oxidize in open air. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Broomhead Posted February 14, 2014 Author Share Posted February 14, 2014 A longer tube and bigger jet will let you run low psi with better stability. The flame will be tighter and a little more robust without the bell reducer. Try a thread protector or spend the extra and buy a coupler. The induction will be stronger so the flame will be a little leaner and cleaner. The dragon's breath won't be quite so orange and the forge should get hotter. Yellow flame means rich and blue means anything from neutral (stoichiometric) to lean. It takes time and experience to tell what a blue flame is telling you. Just remember orange and yellow are rich, not enough oxy. to consume all the fuel. A LITTLE rich is better than a little lean, a lean fire will oxidize the steel in the fire. Hot steel will always oxidize in open air. So...Which is better? I'm confused. Quote Link to comment Share on other sites More sharing options...
EricJergensen Posted February 14, 2014 Share Posted February 14, 2014 A little rich (i.e. yellow/orange), but only a little. So, the comment in the first paragraph is not saying to go all the way to a lean mixture. It's too rich, so make it a little leaner and it will only be a little rich. Quote Link to comment Share on other sites More sharing options...
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