Another forge question

[weo]

Hello all. I hope the start of winter (summer for those of you down South) is treating y'all well.

While I'm tickled to have access to forge and anvil after 9+ months, I'm frustrated with my landlord's forge. It doesn't seem to get or stay hot enough. I'm not used to these venturi forges, so am inquiring from those of you with more experience. My forge for the past 7+ years has a ribbon burner/blower and has no problems getting to a welding (what I'll refer to as a bright yellow) heat and then holding that heat for at least an hour or more. After an hour or so of running this forge, it got to a bright orange at best, with some bright yellow right at the burners but the periphery stayed orange (see pics):

Here's the forge:

After about 30 minutes:

After an hour:

Not an empty or frozen tank...

While these heats are adequate for forging mild steel bottle openers, animal heads, etc, it's nowhere close enough for me to attempt any pattern welding.

Any suggestions on what to adjust? Or, based on the burner design that y'all see, should I focus my efforts on getting my ribbon burner forge set up?

Thanks

 

[Stacy E. Apelt - Bladesmith]

Are you running it all closed up like the first photo?

If so, there is no exhaust ... and thus the flame is choked. You need a open the port in the front or back up at least 1n inch or two to let the hot exhaust gasses out.

 

[weo]

Are you running it all closed up like the first photo?

I've tried playing with as many variables as I can think of. I did notice that it ran differently with both openings shut up like in the picture. I was trying that to keep as much heat in the forge as possible to try to heat the interior bricks up to see if that would help. But that's impractical when actually forging, so they weren't closed up for long. But that could be why it seemed to take so long to heat up.

I have an extra square yard of Kaowool. Is there a quick fix to this box design or should I devote my efforts to getting some 8-10" pipe and make a new pipe forge with the burner lined up to be tangent to the interior diameter of the forge?

 

[Ken H>]

While a venturi burner will get to welding heat, a blower type burner just seems so much better, and easier to adjust. I'd just make a new forge with a blower burner. I am in the process of finishing up a forge with lots of GREAT advice and guidance from Stacy and others. I picked up a 30 lb propane gas tank from the local propane supply place that has plenty of bad tanks laying around as freebies to come and pick up.

 

[Stacy E. Apelt - Bladesmith]

I agree, convert those venturi to blown and it will get really hot.

Out of curiosity, what size orifice are you using on the burners?