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school me on burner angle please

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1st forge 20lb?(12inx12 roughly) propane tank....lots of arguments for every angle of burner. 2 layers wool, kast-o-lite 3000, metrikote...should finish out at cutout holes. Is this angle good? It won't quite hit the ceiling but looks like it will roll along nicely. Thoughts please...thank you.20180328_174942.thumb.jpg.083bfc8727775202138f52c94197096f.jpg

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For my burners, I put them in vertically. After using them, I will eventually move them to an angle like you are using. The biggest reason is that heat rises after shutting off the burners where the flow is not forcing the heat down. So from my experience, I would recommend using an angle like you show in the pics to avoid overheating the burners when I turn off the gas. There may be other factors that the experts can advise on ( @Mikey98118 is one of the best and @Frosty knows a thing or two as well). 

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I think you'll have better conditions in the forge if your burners are aimed at that angle short of the center of the floor rather than the far wall. 

On the other hand I've been seeing propane forges with the burners aimed horizontally across the top so how you have them aimed now may be THE way. If you decide to use this alignment please keep us in the loop, I'm always ready to learn something new.

Frosty The Lucky.

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This is my first my forge so it's all new to me lol, I'm game to try it and let you all know if it sucks. Am I over thinking the heat circulation then by having the angle so high?

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I've been putting propane forges together and using the for a good 30 years and every one is an experiment. If you wanted to change that one to a little more conventional you could just roll it over till the flame was hitting the floor at an angle. 

I'm pretty sure you're going to want to adjust the angle some so I wouldn't weld them in solid till I got it how I like. 

And we want PICTURES! If we don't see pics we won't believe you. It's an Iforge tradition you know. :P

Frosty The Lucky.

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 Awesome thank you! I will be changing it tonight after work as well as setting all my refractory.(hopefully)  I will post many pictures, no pics never happened lol

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You asked for schooling on the subject, so here goes.

The first question asked about burner positioning should be why; not where; their positions are always derivative.  NOT primarily for best circulation of hot gases; that is a secondary concern. Impingement comes first. Where a burner's flame strikes, must be physically tough and thermally up to wear and tear. If your forge insulation is only protected by by rigidizer and a thin seal coat, the flame needs to impinge on a high alumina kiln shelf or an exceptionally tough cast refractory floor, like Kast-O-lite 30. On the other hand, if the forge's hot-face is a 1/2" or thicker layer of Kast-O-lite, wall impingement is no longer a big issue.

Secondarily, comes circulation; fortunately, this takes nowhere near as much encouragement as commonly supposed. It is a strong natural tendency for the fame to circulate within most forge shapes, including box forges. In fact, the only burner position that would effectively interfere with the circulation of hot gases within a forge would be to aim the flame directly toward the exhaust opening!

Note: Positioning burners near the front of a forge makes a close second to the previous example of bad planning.

So, we see that circulation is a weak secondary concern, which should be balanced against other factors, such as how far the flame can go before impinging on them. With a hot-face wall that is only a thin coating, you must aim the flame to impinge on the cast refractory or kiln shelve floor. You would still want to avoid your workpieces, but would also want it to strike as far from the wall it will bounce toward at possible. In that case, I prefer to aim the flame at the near edge of the floor, with only enough angle to assure that it will bounce toward the far edge of the floor, and continue up the wall.

With this in mind you tell me; how should you position and aim your burner?

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I will aim it where you and frosty suggest hahaha... I need to read that a few more times to get it to sink in. Am i following you that you aim in front of your workpiece and let the flame roll over it? Im really trying to learn the rules not just follow others, got a thick skull though.

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So.....i just read forged 101 newest post...it mentioned frosts flange mount for his burners. I had thought about welding  a couple to the inside of my tank and threading the burner directly....not sure how bad an idea that is....thoughts?

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Floor flanges are excellent for mounting burners onto brick or cast refractory surfaces; to use one to mount a burner on a cylinder shape would be doing things the hard way, to the max!

You want your flame to impinge either before or after your workpiece when possible. Keep mulling over what I wrote. Don't bolt your food :D

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However smart you are the more improvements your brain will come up with, right after they are too late to act on; that's what happens to all us other smart guys :P

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Lol! My problem is I'm a terrible troubleshooter....great at fixing and making things though. I need thorough instructions or I overcomplicate things. Doesn't help that everyone has an opinion and Google throws at you. Thank God there's sites like this with people who know how and why things work to steer us along.

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S0 then, you won't mind my suggesting that you continue cutting out your shell, so that to can rotate it to bring your burner up to two inches down from top dead center. Then, use wood or angle iron to trap it there. Mount the burner in position, and check to be sure the flame will impinge near tor the near end of the shelve, but clear of the wall. Now employ a level to mark both ends of the shell for floor hight. Check to be sure the projected flame path will  intersect the floor where you want it, Rotate the shell until it does

You next have the choice of kiln shelve or refractory for a floor. If you go with a high alumina kiln shelve, buy it one inch wider than the opening's width where your planned floor would intersect the hole. Obtain the shelf first, and then cut out recesses on both sides of both openings, for the shelve to slide into. Be sure that the four recesses are 1/8" higher and wider than the shelve.

Wrap your two 1" layers of ceramic blanket around the forge, and then rigidize and fire them. Next, fold a large enough pillow of ceramic blanket between the rigidized layers and the shelve recesses so that it needs to be compressed in order for you to slip the shelve into the forge (don't rigidize this pillow). The shelve should now spring up against the top of the recesses. The pillow will lose its springiness after a few heats, but will still help secure the shelve in place. 

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On ‎4‎/‎10‎/‎2018 at 4:33 PM, Mikey98118 said:

S0 then, you won't mind my suggesting that you continue cutting out your shell, so that to can rotate it to bring your burner up to two inches down from top dead center. Then, use wood or angle iron to trap it there. Mount the burner in position, and check to be sure the flame will impinge near tor the near end of the shelve, but clear of the wall. Now employ a level to mark both ends of the shell for floor hight. Check to be sure the projected flame path will  intersect the floor where you want it, Rotate the shell until it does

You next have the choice of kiln shelve or refractory for a floor. If you go with a high alumina kiln shelve, buy it one inch wider than the opening's width where your planned floor would intersect the hole. Obtain the shelf first, and then cut out recesses on both sides of both openings, for the shelve to slide into. Be sure that the four recesses are 1/8" higher and wider than the shelve.

Wrap your two 1" layers of ceramic blanket around the forge, and then rigidize and fire them. Next, fold a large enough pillow of ceramic blanket between the rigidized layers and the shelve recesses so that it needs to be compressed in order for you to slip the shelve into the forge (don't rigidize this pillow). The shelve should now spring up against the top of the recesses. The pillow will lose its springiness after a few heats, but will still help secure the shelve in place. 

You wouldn't happen to have an image of that example of burner tube placement, looks like, do you?  I think I understand, but I am at the point of cutting my hole and all research comes up with a lot of conflicting ideas.  I have already gotten the stuff for my lining.  Kaowool, 2 layers of 1", Satanite for the lining and mizzou to cast the floor.

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I did, but it was part of an out of print book. The instructions that went along with it called for placing the burner hole(s) two inches down from top-dead-center on a five gallon propane cylinder. Less straight forward is power sanding/grinding the holes into a slightly elliptical shape, so that the burner port(s) would allow the burner(s) to be aimed on a tangent, rather than being aimed straight into the forge interior. All this was recommended so that the point of flame impingement could be close to the near side edge of a floor made from a high alumina kiln shelf.

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