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I just finished putting together my new forge and was wondering if the burner flames looked neutral to you guys. The only reason is because if I was wondering is because I have to let almost double the amount of air to the back burner as the front burner to achieve a neutral flame on the back burner.

Was just looking for some someones elses opion if it looks ok.


attached is a short clip of the forge with burners running 

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Welcome aboard Rory, glad to have you.

Both burners appear to be running a little rich to me but I like them running a little rich, prevents scale forming IN the forge. They're both getting lots of burning fuel in the forge which is good.

With large openings in both ends the only reason for one to be burning differently than the other must be a construction detail. The front burner is doing a better job of drawing combustion air so I'd be trying to make the rear one as close to exactly the same as I could. I haven't messed with linear type burners in a long time but the principles are the same regardless of type.

Needing to run the choke wide open on one means it's gas jet isn't as efficient. Several things could be the problem with the jet:

1, the jet (orifice) may have a bur or some debris partially blocking it. Did you use thread tape or paste? It's REALLY easy to have a little shred of teflon tape happen screwing the fittings together and it WILL find the gas orifice or worst possible place to block. It's why I use paste thread dope. You really need to use thread tape/paste, hose, etc. rated for propane it's some sneaky tricky stuff.

2, The jet may have gotten moved out of alignment so the gas stream isn't aimed straight down the center of the mixing tube. It might have gotten turned when tightening the plumbing or bumped sideways. 3, The gas supply may be uneven but I don't see any visible signs in the construction so I doubt that.

Those are my thoughts, the jet is partially blocked OR it got bumped or twisted out of alignment.

One last little bit of advice. Next time you shoot video CLOSE THAT DOOR! Back lighting makes photos, videos etc. really hard to see. No camera has the human brain filtering images so what you see in person is almost never what the camera catches. Other than back lit, good job with the video shows what we need to see and hear.

Frosty The Lucky.

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awesome! Frosty  Thanks so much for the input. This is my first forge and as much as I read and watch videos for information its still nice to have a someone with some experience look at it and say it looks alright/normal. Thanks again. Ill try to get another video without back lighting if I get the chance. 

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You're welcome Rory. I highly recommend you spend some time reading the gas forge and burner sections of Iforge. Almost anything you need to know has been asked and answered many times. Glenn and crew have been archiving posts for 16 years and I don't know how many posts are organized by subject.

When you're trouble shooting only change one thing at a time, test observe and write down the results, it's a LOT faster than just trying stuff till it works or you get tired and give up. 

Well, wouldn't you know it, you posted while I was eating dinner. They're running rich, more than I like. Think CO generators. I'd like a better look at the fuel supply set up on the burners. Close ups of the gauge doesn't help, you can just tell us what psi you're running. 

What's the diameter and length of the mixing tubes? What's the drill size you used for the jets?

Hopefully someone with more experience with this type burner will speak up, it won't take as long to figure yours out.

Frosty The Lucky.

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I would suggest you change out your gas jets for something with smaller orifices, so that you can raise the gas pressure. And check for a burr or inclusion in the jet on the rear burner while doing the switch.

Could you tell me what brand that propane cylinder you used for a forge shell is?

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Frosty and I both think that there is a burr or partial obstruction in the gas jet of your rear burner; that is easily rectified.

Bringing both burners up to snuff is a different matter. Your flames are reducing, and too long; even while still reducing they will shower your work with super heated oxygen, creating scale. Presuming that those are 3/4" size burners, a .023" MIG tip would normally be just a touch small, while an .030" tip would be just a touch large. BUT, you stated that they are only 1" long!!! The tips should have been 1-1/2" long. It would be quite a hassle for you place the side holes in your reducer fittings where they would need to go, to properly mount the longer MIG tips now. So, the smaller tip is the logical move at this point. BTW. if you should decide to move the cross pipes for longer tips, use a 2" to 3/4" reducer fitting next time.

I take it back. I took another look at your burners, and your cross pipes are placed in the right area to mount the longer MIG tips, so that should be your first move. Also, I would still recommend the smaller tip, to induce more air, because your reducers aren't the best size to do so. Also, either chose Tweco tapered MIG tips, or spin the tips in a drill, and file them down to a blunted taper, similar to the Tweco tips.

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