T Burner Illustrated Directions

[Mikey98118]

I would prefer to keep my feet out pf this bear trap, but you have serious need of help. Your photos show steady flame improvement, BUT the forge shell is getting way too hot around the burner portals. Try changing how far inside the refractory your burners sit. If you don't get relief from that, try to find a blacksmith group in your area to show the forge too them, and GET HELP SUPER FAST!!!

[Goods]

Those jets of blue flame coming up around the mixing tubes are pretty scary! Must be a lot of back pressure to get jets like that. (Sorry, I’m not a gas forge guy yet, so I can’t offer much help, but keeping working on it. I plan on building one at some point, and you never know, I could run into the same problem.)

David

[Jasent]

Is that forge not sealed? This pic makes it look like it’s just wool and no refactory?

[Baconchsbrgr]

Big thanks to Frosty and the group around here for the insight and guiding new people through the process. I've been reading through these forums for a while now; finally signed up to get the T-burner designs and started a basic forge for a proof-of-concept. Built a down-sized T-burner (used the ratios in the blueprints to go down to 1/2" instead of 3/4") but am a little lacking in infrastructure here - I don't have a drill press and am using a smaller, handheld drill and a vise attached to a stump. Drilled and tapped holes, but am off about 10 degrees on the MIG tip. Fired up the forge anyway, did a leak test and operated fine at about 15PSI. Heated metal well and got a good air-gas ratio with a little adjustment. No dragon's breath and no issues with the burner found.

My question for you is whether or not this misalignment will slow me down or seriously damage anything or is it serviceable to run until I build a more long-lasting forge down the road? Is there anything I can do other than getting a new T-fitting and re-drilling it?

Side note, yes, I know I'm using a bunch of fittings there; I had access to them and a propane regulator on a hose and it seemed to work instead of getting the tubing. Will probably go that route instead with the next forge build, just wanted to get something working for now so I could get a feel for this craft and learn. 

Appreciate any feedback or recommendations. I've already learned a ton just reading everyone else's questions.

 

[Buzzkill]

The misalignment of the mig tip in relation to your mixing tube will most definitely affect the performance of the burner.  There's no getting around that.  However, you asked if it will slow you down or seriously damage anything.  You will most likely burn more fuel than you would with a well tuned and properly aligned burner, and it's not likely that you'll be able to reach forge welding temperatures.   On the other hand there's little danger of it blowing up in your face or anything approaching that level of danger.  You may be able to get steel up to forging temperatures and make some items with what  you have built.   Also, you are probably not inducing enough air due to the misalignment and the depth of the mig tip orifice in the T, so you'll probably be generating a fair amount of CO.  You need a detector and adequate ventilation if indoors or you'd need to operate that outdoors to avoid inhaling too much of that stuff.

There's probably not much you can do for the alignment without starting with a new T.  If you were really close you could try gently bending the mig tip towards center, but by my eye you are too far out of alignment for that.

Side note:  The thread tape is not needed or even desirable where the mixing tube threads into the T or the reducer fitting at the other end.  In that portion of the burner even if you do have tiny leaks they will not be noticeable or cause any problems.   On the flame end you will cook the tape for sure if the burner is running anywhere near right.

[Baconchsbrgr]

Got it; I am only running this outdoors already due to a healthy fear/respect for propane, high heat, and toxic gasses. Will probably continue that way unless I open up my garage to work. If it's not going to hurt anything and just give me a less-than-ideal mixture I'll keep using it for now until I get a new one made up. Just wanted to check here and make sure.

 

Thanks for the note on the thread tape- that's easy to fix and I'll remove it. Tape was cheap and I got a little tape-happy, ya know?

[Irondragon Forge ClayWorks]

Welcome aboard Baconchsbrgr... Have you read this yet?  READ THIS FIRST  It will help in getting the best out of the forum with tips like editing your profile to show your location and may help in staying off the moderators radar.

[bertie_bassett]

a little tip for helping with aligning your tap.

tap from the inside out, as long as your drilled hole is centered then you simply have to keep the rear of the tap centered with the fitting. 

only works for parallel threads but should get you close enough.

[Frosty]

If you use the floor flange and close nipple for the jig. Do NOT remove the T until you're done. I only change out taps for the drill bits, drill, tap, install next fitting, drill & tap. This keeps everything as perfectly aligned as is reasonable without high end equipment. If you leave the floor flange clamped down you can make T burners in batches. 

A drill press is second only to a lathe.

Frosty The Lucky.

[Keeley S.]

Hey all,

Long time lurker, first time poster.  I have a freon bottle forge w/ 2" ceramic blanket that's rigidized, coated with HW Kalakast AR adtech high alumina refractory with a removable "shelf" casted from the same refractory.  I haven't coated with an IR wash yet but that's in the plan. 

Anyways, I am running a 3/4" T-burner as spec'd in Frosty's directions.  I am getting a good flame (I think), I can get a pic tonight if needed.  I am running it outdoors about 30 metres (98') above sea level.  When I first fire it up, the flame seems quite unstable and sputters and occasionally goes out until the forge is up to temp.  Also, it's happy place seems to be around 12psi.  

Could this be a sign of poor air induction and just needs the mig tip (0.035) trimmed, or am I way off base?

Thanks for any assistance, and sorry if I am rambling

Edit: just went and checked, my burner was about 3/8" from the inner wall, so I put it about 1" into the insulation, it must've slipped at some point.  I didn't test yet to see if it helped.  

Cheers,

Keeley or Sully, whatever's easiest

Edited July 11, 2020 by K. Sullivan
Missed some info

[Frosty]

Welcome aboard Keeley, glad to have you. Some still pics in dim light will help us evaluate what's going on. One in the door when you first light it so we can see the flame as it enters the forge and another from the side so we can see the exhaust coming out the doorway. 

Then another couple pics from the same angles after it's heated up. 

T burners are susceptible to breezes outdoors, especially before the forge comes to working heat to keep them lit. If it smooths out after it warms up it's probably not a big issue.

Pull the burner back out of the liner, you only want it just into the ceramic blanket, 1/2" is usually more than deep enough. It's not an exact thing but don't go very deep or the burner will tend to get a lot hotter than is good. A hot burner tends to pre-ignite and burn in the burner instead of in the forge. 

Frosty The Lucky.

[Keeley S.]

Hi Frosty,

Thank you so much for your reply, it was a big help.  I moved the burner outlet as recommended, it's about 1/2"-ish into the blanket.  I don't know if it was due to that adjustment or if it was because today was relatively breeze free at my place for a change but it started up with only a small sputter that lasted 3-4 seconds then no issues after that.  I took a short video of the flame just after flashup https://youtu.be/pwdgGqOQlo4 .  Also, here are some pictures of my setup(1st pic), flame on startup(2nd & 3rd), flame after heat up(4th & 5th), and as best a picture that I can get at present of the dragon's breath(6th):

 

[Keeley S.]

So after running it this evening I discovered that I rushed by taking them earlier in the day(even though it was dark-ish), way more detail in the dark.  Video:  https://youtu.be/A1ufvkVw070

after startup

exhaust after start

After heat up

Exhaust after heat up

[Frosty]

Looks pretty good from here. A sill will help  contain the fire in the chamber longer. By sill I mean a low barrier across the opening, say 1" - 1 1/2" high. As is the flame impinges the floor and a good portion flows straight out the opening at floor level. A sill deflects part upwards into the swirl the burner angle initiates.  The opening can be much smaller, until it begins to effect the burner flame.

Nice cart, it's a lot like mine. Have you used it, how does it heat steel for you?

Frosty The Lucky.

[Keeley S.]

I can always cast a sill to both ends of the removable floor.  I was actually thinking today that I should figure out some sort of door for the front and back outside of a brick propped up against the opening, the ground isn't the most level so the brick can get a bit tippy. 

     The forge works great, I have gotten my wrought iron to forging temp, I could probably get it to welding heat, just haven't had anything to weld yet.  I took a chance on the Kalakast for the castable and it seems to do pretty good so far, it gets to forging heat in about 5 minutes.  I also put some borax on the floor to test and it didn't touch the castable. 

     The cart has worked really well so far,  I have my piping run through it, and gauge/ball valve mounted to the opposite side of the forge so I can get to the valve quick if needed.  The burner runs great, and easy to build.  Thanks for the detailed instructions, it made life so much easier.  I come from a technical background but my brain isn't what it once was, and I can't wrap my head around some directions that are out there, so something clear and concise is a life saver.

Cheers

[Frosty]

5 mins to working temp sounds good to me. You don't need a "reason" to weld beyond giving it a try. Make a fireplace poker with a welded point maybe, they make nice gifts. 

I wouldn't bond the sill to the floor until you know if it improves performance enough to be worth it. I just cut a K-26 Insulating Fire Brick. (IFB)

What I like for a forge porch is a simple bracket that supports a split 3,000f hard fire brick level with the opening. The porch doesn't care how hot or what gets put on it and provides a good place for door baffles. My current NARB forge works nicely with a couple hard fire bricks laid in front of the opening with a split brick laid in the integral porch (that turned out badly). the split brick on the porch increases the height of the sill and makes the stand for the baffles. 

That forge is a prototype and needs to be rebuilt but it proved the NARB and works okay. I'm afraid I've never built a forge I was actually HAPPY with, every darn one has flaws. <sigh>

Frosty The Lucky.

[Tradguy]

Frosty help please! I built a forge by your plans (i think) but im having a hard time getting good welding temps. It seems to peak in temp then starts dropping. I have a pyrometer on it. I feel like its starving for air after it peaks. Ive trimmed the .035 tips 3 times. 
I have 3/4 tubes 6 in long with a coupler on the flame end.  The only thing i think i did different was used 1x1 t and reduced it to get to the 3/4  My firebox is 8x8 , 18 in long with about 1 in kaelwool lining. I blocked off about 4 in of the length for normal work so im probably heating about 14 in. 
What am i doing wrong? 
Thank you in advance. 

[Frosty]

Welcome aboard Tradguy, glad to have you. If you put your general location in the header it'll make it much easier to network with folks within visiting distance a lot of information is location sensitive.

The 1 x 3/4" bushing reducer can screw up the flow and hinder combustion air induction. I need a look straight through the intake ports of the Ts to get an idea of the jet position and alignment.

You mounted your burners awfully close together so the back pressure they're generating is probably interfering with induction.

Last you have one end of your forge blocked causing more back pressure. 

1" of ceramic blanket isn't really enough, better than nothing but not much. It also doesn't look like there is a hard refractory inner liner. bare ceramic blanket refractory is very delicate especially at forge temperatures. Worse the vitrified fibers that break off float in your breathable and they bad news for your lungs. Think mesotheleoma or silicosis. 

There are a number of forge building threads in the "Forges 101" subsection with plans and links to proven forge plans. The "Burners 101" subsection contains the most current discussions about burners and has plans or links to plans to build proven burners. 

As built your forge isn't likely to reach welding temps and if it does isn't likely to hold temp. Worse it looks from here your liner is actually dangerous.

Stick with us, we'll be more than happy to help you make your forge as screaming hot as it should be.

Frosty The Lucky.

[Tradguy]

Thank you much! I will make some changes and get a pic of the jets. 
I didn’t think about back pressure. I was trying to keep heat in but that makes sense. 
i moved the burners closer together as I thought that was part of my problem. I have a hole to move them back to 5 1/2” apart. 
i will be adding refractory!

[Tradguy]

Frosty, im ready to order some refractory. Ive read some recommendations here and im thinking 2” kaelwool with kastolite refractory coated with itc 100. Ive also heard some talk about alumina bubble on the floor. Thoughts or changes? I wanna do this right this time. 
I experimented with opening the back end of forge but got the same results. Temp peaked then started falling. Maybe I didn’t have it open enough and maybe my liner isn’t helping. I do have my kaelwool liner coated with rigidizer. Thanks for the help!

[Buzzkill]

What are you using for a propane supply?   If you are using a single BBQ size tank then 2 of the 3/4" burners trying to achieve welding heat may be cooling the tank enough to drop the pressure a bit before you reach your desired temps.  Does the roaring sound diminish at all about the time you see the temperature drop?

[Tradguy]

Im hooked up to a 250 gal tank. I dont notice it diminishing. I keep an eye on my rugulator for frost. Haven’t had any problems with that. 

[Buzzkill]

Just to be clear here.  You actually see a drop in temperature rather than just a leveling off, is that right?

You may want to try to run just a single burner to do a test run.   You can't expect it to get a forge of that size to welding heat with one burner, but you should be able to see if the pattern of peak temp then dropoff repeats.  If it still happens the problem isn't the 2 burners fighting each other.  If the problem goes away, then the second burner is at least part of the issue.

8x8x14 inches is still a bit large for 2 of the 3/4" burners, but if you put in another inch of ceramic fiber blanket all of the way around that will bring it comfortably within the range of 2 burners.

[Tradguy]

Yes sir it’s dropping. I have a pyrometer on it. Frosty suggested i have too much back pressure as well as not enough or the right liner. It seems like its starving for air when it starts dropping. Im getting a lot of big orange flame coming out. It will maintain forging heat when i have the pressure lower but when i turn it up for welding it just won’t maintain good welding temps. I have welded but i have to do it before the drops. I ran it yesterday without taking stock in or out and same results. 

[Buzzkill]

In my mind at least neither of those things explains the symptoms you have.  I would expect 2 burners that can't play nice together to reach an equilibrium of subpar performance and the temperature to level off there rather than peak and drop.  Likewise with less than ideal insulation I'd expect the forge to dump heat faster than preferred and hit an equilibrium of heat in/heat out at a point below where you want to be rather than a peak and a drop.

If your burners were pulling in exhaust from the openings that could affect performance, but again it seems strange to me that there would be a drop in temp after the peak.  I keep coming back to the fuel side of things.   Do you have a needle valve you could use to temporarily eliminate the regulator or a different regulator you could try?

In the vein of trying the easy things first I'd recommend running a single burner to check for the peak and drop phenomenon before making any other changes though.

Frosty has far more experience than I do in this area, so you should definitely take his advice over mine if he has other ideas.