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I Forge Iron

Problems with natural gas forge.

Jim Erickson

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The first pic is of the cool spot I have encountered in my new set up.  It gets plenty hot all around it, but right below the nozzle seems to be cooler.  I just fired it up tonight, but I was wondering if anyone had any suggestions or improvements I could make to make it better.  I can post more pics if anyone needs to see more. 


The gas comes in through 12 pipe, then the hair dryer is 1 in, they combine and my nozzle down into the firebox is 3/4.  I used a dimmer switch to control the speed of the blower.


I'm thinking I just have the blower running to hard?  It is not igniting until after it deflects off the firebrick?  More testing is required, but I was hoping to have some suggestions before I start fiddling with it tomorrow.


Thanks in advance for the help!





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The nozzle is too close to the work. If you look at an oxy acet torch flame you'll see the flame is in three parts. The primary cone is the  well defined blue flame at the center. Right at the very point is the hottest part of the torch flame. The secondary flame is the larger more transparent flame surrounding the primary and is hot but more suited for preheating, it's hot but softer. Lastly the tertiary flame is the looser outer flame it's very soft, sometimes feathery and is the preferred zone for soft heat such as needed for annealing non-ferrous metals. As I recall the three parts of the torch flame have proper names but they're gone from my much dented up old brain.


What's happening in your forge is the flame is extended into the firebox till the floor is inside the primary flame. The fire isn't even burning where the fuel air flow is hitting your work. Just move the torch up till the work is beyond the tip of the primary flame and it'll work a treat. It should be screaming hot.


Easy fix. Nice looking forge.


Frosty The Lucky.

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Thanks Frosty, moving it up worked great, the only thing I had to do was put an additional layer of insulation on the top to keep the flame inside the box. 


The steel I ordered should be here this week sometime, and the temps might actually be above zero for the first time this winter, the stars are aligning to get some time hammering!

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  • 2 weeks later...

Frosty you are a wizard! I was thinking similar but when you mentioned the parts of the flame the bells started ringing :D Yeah I don't remember all of the flame parts either. Had to know them for final test in welding school but that was nearly 40 years ago. Its gone!

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  • 3 weeks later...

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