Flame Check and Advice Please

[evildeadash]

 

So i built a pair of 3/4 sidearm burners for my propane tank forge. I calculate the volume to be around 460 cu in. I know two 3/4 is a bit over kill but two 1/2 burners was going to be under sized so I plan to turn down the pressure or turn down one burner once I get the forge hot.

Anyway, I ran the forge a bit this weekend and the "dragons breath" seemed a little overwhelming. I pulled the burners out today and tuned them in a vice, then re-install and adjusted a little. The dragons breath still seems a bit much once the forge gets going. I'm attaching some pics of the forge running at 5 psi and 8 psi after just lighting it. Also a pic of both pressures when the forge is really going and what I think is a bit much dragons breath. 

Best I can tell it seems like the burners might be running a bit rich. I have a .025 mig tip installed in each. The forge is lined with two layers of 1" kaowool, kast-o-lite 30 over the kaowool, and layer of Plistix for efficiency. 

I shined up a piece of flat bar and put in forge to see how much it would scale. Once it got orange hot I pulled it and brushed it but no scale came off. Put it back in and pulled at orange hot again. Tapped a few times with hammer and got a little bit of scale to come off. This leads me to be believe that it might be too rich but I'm definitely not an expert. 

Any help you guys can offer would be much appreciated, thanks.

 

[Latticino]

Easier to tell in low light, but does seem to be either a little rich or possibly still the refractory outgassing as it cures at high temperature.  Have you baked it thoroughly at high temperature yet?

If too much reduction you will have to try to induce more air by shifting the orifice longitudinally near the burner port (listen to the roar, typically louder is more air induction).  Also check if it is centered in the mixing tube.

[evildeadash]

Yes I baked it after I built the forge a few weeks ago. Also ran a pair of T burners in the forge for a while before making these sidearm burners. From research I've done these sidearm burners are supposed to be easier to tune, that's why I switched. No offense to Frosty 

[Mikey98118]

Outgassing isn't the [problem this time. Those burner flames are green. Larry Zoeller choose to build side arm burners that have been changed and improved with a special "T" fitting; its shape causes incoming air to swirl. You can order the right pipe fittings from Zoeller Forge.

[evildeadash]

Picked up some .023 mig tips today, will try those out. If I end up being to lean I'll just have to add some chokes I guess. The "special" T fitting Zoeller uses on the newer style is a WYE Tee. They are a little pricey and not available locally. I'll post an update tomorrow.

[Mikey98118]

How pricey are the fittings for his "Z" burners? He recommends them over this earlier design anyway.

[evildeadash]

$40 - $50 most places. Not crazy but a bit much for 1 fitting. 

I tried the 023 tips and was still rich so I don't know. 

Started playing around with frosty T burners again out of frustration with the sidearm. I had to cut the 023 mig tip down all the way to about 1/8 left to get the flame more blueish. Stable flame I could turn up to 20 psi and down to 2 psi without it blowing out. I know I'm still rich with still burner setup as well. I can blow a little air into the T while running and get a great dark blue flame. It has to be this Louisiana air. I'm only at 56ft above sea level so it's heavy and sometimes very humid. Maybe a 1 1/4 x 3/4 Tee for more air? 

Thanks for your responses Mikey, I appreciate the help. 

[Mikey98118]

9 minutes ago, evildeadash said:

Maybe a 1 1/4 x 3/4 Tee for more air? 

This isn't my burner design, but it would be reasonable to expect this change to soup up burner performance. On the other hand, we don't seem to have much idea what is wrong with your present "T" burners. Personally, I would be pleased to see you experiment this way. Whether you actually need to do so...fairness dictates an answer of "probably not."

[Frosty]

For which burner are you contemplating a 1 1/4" x 3/4" T? It's getting silly for a T burner. I can't say about a Z burner though, what did Larry say? 

Frosty The Lucky.

[evildeadash]

For the "Frosty" T burners. I know it's unusual but don't know how else to get more air in the mix. Bigger mig tip couldn't be the answer, could it? Ran rich with 023 at pretty much all lengths. 

I already have 1 1/4 x 3/4 for the zoeller burners. Putting these to the side for now. Getting better results from the T burners now. 

[Buzzkill]

If it's running rich with a .023 mig tip and the correct T then you have an air induction problem or a fuel leak in the T.   The most likely scenario is that the fuel stream is not centered well in the mixing tube.  We've also sometimes seen fuel leaks where the mig tip screws into the tapped fitting.  When that happens additional fuel is pulled in with the air, resulting in a rich burn.  You should not be running rich with a .023 mig tip in a properly constucted 3/4" Frosty T burner.

[Frosty]

How far down the mixing tube do you have the mig tip poked? Is it aligned STRAIGHT down the tube?

Shouldn't be running rich Buzz? If he'd followed the directions it COULDN'T run rich. Done right you have to be careful tuning a 0.035 mig tip in a 3/4" T or it'll run lean. A friend of mine runs a 0.040 in his but it's way fast and makes a lot of dragon's breath.

Frosty The Lucky.

[Mikey98118]

4 hours ago, Buzzkill said:

f it's running rich with a .023 mig tip and the correct T then you have an air induction problem or a fuel leak in the T.   The most likely scenario is that the fuel stream is not centered well in the mixing tube.  We've also sometimes seen fuel leaks where the mig tip screws into the tapped fitting.  When that happens additional fuel is pulled in with the air, resulting in a rich burn.  You should not be running rich with a .023 mig tip in a properly constucted 3/4" Frosty T burner.

Wouldn't a list of symptoms for "T" burners go down very well? Perhaps it could be attached to the posted instructions?

[evildeadash]

Thanks for the replies guys. Buzz/Frosty I complete agree that it shouldn't/couldn't be running rich and I really wish it wasn't lol. I just want to get back to forging . Anyway the best I can tell the tip is centered. 

I made a 1 1/4 x 3/4 burner this evening and ran some test with different tips. Also ran more test with a 1 x 3/4 T and different tips. Hopefully the pics below will be helpful to you guys. Flames definitely look better, a lot more blue and minimal dragons breath. Also the unused burner port was plugged with scrap kaowool.

 I know I'm gonna get fussed at for using galvanized Tee's but that's all I could find locally. Nearest black iron supply is 45 mins away and I couldn't get there today. Rest of the fittings are black iron and brass. Thanks again guys.

[Irondragon Forge ClayWorks]

Any time you have to use galvanized, that may get heated, soak it in vinegar over night to remove the coating making it safe.

[Frosty]

Put tape or something over the pressure gauge it's doing NOTHING but confusing you! You're so preoccupied with different pressures you are ignoring the single most beneficial aspect of a naturally Aspirated burner. Once tuned the propane pressure doesn't matter the fuel air ratio remains the same. FORGET the gauge!

Yeah, it's best to keep galvy away from a forge but you should be okay where it is IF you plug the intake ports when you shut it off so chimney effect doesn't get it too hot. Two balls of aluminum foil will work.

The problem with the 1 1/4" T burner is the 1 1/4" x 3/4" bushing reducer and how short you've cut the jet. The propane stream will have expanded to the point it's impacting on the reducer and seriously reducing air induction. 

For now forget the 1 1/4" x 3/4" burner it's a non starter, for now anyway.

I've never had to cut a jet back much past center as seen through the intake ports, even before I started using 1" x 3/4" Ts. I had to shorten the jets almost 3/4 of the way back when I was using 3/4" x 3/4" Ts and a 0.035 jet but they were more susceptible to breezes and back pressure.

I also don't like how the copper tubing is bending off the top of the burners. There's a good chance it's knocking the jet out of alignment. If the propane stream isn't flowing straight down the tube it's easily probably the burner would run rich no matter how small the jet. It looks like you still have all that weight hanging off the burners too. If the jets move every time you jiggle the forge it will never burn well. Haven't I told you ALREADY to get all that heavy junk off the burners? It's like you don't want them to work.

Mike: I've thought about doing a pictorial tuning segment, which should cover the problems but I'm seeing so many mix and match online video burners I don't know how much good it would do. 

This one for example. Evil doesn't have a tuning problem, he has fundamental construction errors that need to be made right. Worse he's jumping between two very different burner builds and one T with problems and another T that probably can't be made to work. He's in too much of a hurry for a pictorial flame evaluation and tuning guide to do any good.

From the looks of it I don't know what I can do if he won't start addressing the problems I told him about earlier. There's all that weight hanging off the jet. Hanging directly off the JET! I've already told him to get it off there and why but it looks like he's decided to try other guesses instead.

It reminds me of the old joke, 'I've cut this board three times and it's still too short!'

Frosty The Lucky.

 

 

[evildeadash]

Frosty I've scanned every post in this thread and don't see where you talked about the tubing weight and pulling down. I definitely agree with you and will make those adjustments. The tubing was hooked up as so for temporary testing. I'm not ignoring any suggestions and welcome any constructive input.

I tried the 1 1/4 Tee for testing purposes and out of curiosity/suggestion from Mikey. I got data from the test either way. 

I wanted to try the sidearm burner because it seemed easier to tune but that doesn't seem to be the case for my setup. Like I said in an earlier post I've put it to the side for now and only working on a Frosty T burner.

I will secure the fittings and copper so it shouldn't be pulling down tomorrow and only work with the 1 x 3/4 T setup. What size mig tip do you suggest to start with for my conditions? Remember I'm not far above sea level, the air here is heavy and often humid. Thanks again for all you guys contributions to this community. 

[Buzzkill]

You can check the alignment of the jet with the mixing tube by hooking up a pressurized water source to the burner where you would normally hook up the propane.  If the water stream shoots down the center or really close to it then that's probably not your issue.  A plastic syringe and some tape might even suffice here.

It's a bit harder to check for gas leaking where you screw the mig tip in.   If you want to be sure it's not leaking you can solder the mig tip to that fitting. If your fuel stream is centered in the mixing tube, and all the other parts are as specified in the instructions, a fuel leak inside the T is about the only thing I can think of that would produce a rich burn with an undersized jet.  

The closer to sea level you are, the greater the concentration of oxygen in the air, so that should only work in your favor.  I doubt the humidity plays a significant role in the performance of your burner unless it's to the point where water mist is actually being drawn in.  It's fairly humid where I live a good amount of the time and I haven't noticed a significant change in flame behavior due to the relative humidity of the day.

Don't worry too much about the flame blowing out at moderate to high pressure before the forge is hot.  Once the forge interior surpasses the ignition temperature of the fuel/air mix you can turn the pressure up and it will not blow off the end of the burner.

You should be able to use a .035 mig tip for the burner if everything is constructed correctly and you don't have extra fuel being drawn in with the air.  Before you trim the tip it would be expected to run a little rich, but you should be able to trim it back a little at a time to get the desired result.  Don't forget to ream the mig tip orifice with a torch tip cleaner after shortening the mig tip.

I think Frosty was confusing you with another guy who had a lot of fittings and copper line hanging off his burners, but the principle is still the same regardless. The fuel stream needs to be as close to centered as we can reasonably get it, and we want it to stay that way in order to get good performance from the burner. If the jet can move even a little bit off center it can make tuning a nightmare.

[evildeadash]

Buzz, thanks for the info. Didn't get as much shop time after work today. The warden aka "wife" pulled me away then had to get kid from jujitsu. I did manage to get the valves/fittings secure so they and copper line shouldn't be pulling down anymore. Also drilled and tapped a new 1 x 3/4 T incase my old one is off any. Took extra special care make sure I was dead center as possible with drill press, used the floor flange method. 

Should be able to get the 035 trimmed and test it out tomorrow. I may also try to solder the tip to fitting to eliminate that possible variable. Thanks again. 

[Frosty]

On 3/17/2021 at 7:33 PM, evildeadash said:

Frosty I've scanned every post in this thread and don't see where you talked about the tubing weight and pulling down.

I was thinking of another fellow with a similar looking hook up. Worse than that, he may be trying a different set up and my irritation is completely undeserved as well as misplaced. I sincerely apologize, it's my bad. 

Have you ever found yourself in a conversation and thinking, "What a butt  head!," only to discover you're the butt head? That's the royal "you're," I'm not referring to You, the Evil.

Have you looked at the T burner illustrated directions pinned in the propane burner section? The part to connect the tip to the T fitting may not be what's listed in the PDF. Things have changed since I wrote them. How the fitting screws into the T isn't as important as the ID is small enough you can tap it to match the mig tip. 

Another detail that has changed is the tap. There are many threads and pitches used in modern mig welders so what I called for probably isn't going to work for the mig tips you have available. What works well is to buy from a welding supply, they will have the appropriate tap on the shelf. They'll match it by looking in the cross over book. The proper drill bit necessary to drill for THAT tap is printed on the tap itself and most cases the package it came in. The welding supply will have those as well.  Getting all three at one stop and knowing they match properly beats saving a couple dollars and taking chances.

Once you have THE drill bit you can use it as a go / no go gauge when you select the brass fitting to mount it to the T. You want one that the drill bit fits with no slop OR won't go in at all. Smaller is better, you're holding the fix in your hand. Yes? 

Another method of mounting the mig tip I'm beginning to like a lot is to use 1/8" scd 80 black, close nipple, the ID is almost perfect to thread for a mig tip. I recommend you chase the ID with THE drill bit so, mill scale, weld seam, minor imperfections won't mess up taping the threads. Use the same method I lay out in the plans to align everything but I enlarge the ID of the 1/8" nipple to the last 3/8" where the mig tip threads in. There's no reason to tap the entire length of the nipple when all that's in play is the bottom fraction of an inch. Make sense?

Once you have the T clamped to the drill press do NOT remove it until you've drilled and tapped everything involved with the jet. 

A street elbow screwed onto the T helps prevent having a lot of leverage against the jet so it'll stay aligned more reliably. Also if you can find a 1/8" male pipe (MPT) to 3/8" FPT elbow you can connect the propane hose directly. I like copper for the final supply to keep rubber hose away from forge heat. It isn't an issue if the burners and openings are in the right positions. 

One of the above methods for mounting the jet makes it unlikely they can be bumped out of alignment.

On a last note about connecting the propane supply. Put all the valves and stuff at the regulator end of the hose so there's no more hanging off the burner than necessary. Unless all you could find was a regulator with the hose permanently connected. Those are the BANE of keeping burner jets aligned. If you MUST have a gauge there should be a plug on the regulator, it's there for a pressure gauge. Right next to the pressure adjustment knob. Sensible eh?

It isn't as complicated as it sounds, with a LITTLE practice you'll be able to build and a T burner in 20 minutes give or take. 

Do NOT expect any two home built burners to be alike, certainly not close enough to be able to standardize how far to trim the jets. There is just too much variation in components but close is good enough when we're talking a T burner. 

Please don't let the frustrated, maybe low blood sugar, cranky Frosty make you hesitate to ask for my help. 

Frosty The Lucky.

 

[evildeadash]

No worries Frosty I can definitely understand your frustration at times. 

Yes I did review your T burner guide and found the correct brass 1/8 npt x 1/4 flare fittings. Local shops had some thick walled ones you could drill/tap and some thin wall ones that could not be used. I recommend anyone going shopping for these to bring a mig tip with them. I used Tweco style tips and a 7/32 drill bit combined with 1/4-28 tap worked fine. For drilling into the T for the 1/8 npt tap, an 11/32 drill bit works really well. My fuel cutoffs are on the tank side of the copper tubes not on top the T's. 

Anyway I left work early and spent the afternoon working on these burners. I am happy to say I think I got them running correct now and they are burning hot! Flame is a beautiful dark blue and very little dragons breath. See pic below and let me know what you think. I'll let you know what I had to do other than securing the fittings and copper tubes. 

 

 

[Mikey98118]

If anything, those flames may be more a touch lean. A little larger orifice size in the MIG tips will take care of that good and easy. If this amounts to a problem, you can make mine vanilla

[Buzzkill]

EDA, I'm curious about the changes you made.  It also may be of some use to others in the future, so take a minute to share the info if you don't mind.

[evildeadash]

Maybe Mikey but I'm afraid to touch them lol. Don't know why but it's finicky. Any change and they want to get rich again. 

No worries Buzz I was going to share what I had to do. No matter what I did with 035 tips it would run rich. Ended up having to use a 030 tip trimmed down halfway on the closest burner. Tried same thing on the back burner and it would run rich. The back one took a full length 025 tip to get right. I don't understand why, it's gotta be something about the volume of air or whatever around here. Thought maybe the burners might be starving each other but I get the same results when running them individually. 

 

[Frosty]

To eliminate position on the forge or in the shop or whatever being the reason swap burner positions and see how they burn. I'm betting it's the burners but I'm surprised you got that good a burn with a 0.025 mig tip. They both look a little lean but the back is lean. An easy to see is to put a piece of clean steel in the forge. If it scales up the burners are lean if not until you remove it from the forge they're probably good. 

I can't find a pic in through the intake ports of  one of my burners I may have to go get a couple tomorrow when it warms up a little. I think mine are all within 1/16" of each other for where they're in tune but I could be wrong, I haven't compared them in a long time. 

As it sits all your forge needs are some baffles so it's not blowing all that heat out those doorways. 

Frosty The Lucky.