I live in Southeast Alabama near the Florida Line. I started forging about 5 years ago and need to upgrade my forge. I am hoping to get some sage advice from folks who know much more than I do about this topic. In essence, what I am wondering is should I simply upgrade my venturi burners to forced air and move them to the side of the forge body rather than on the top. If I should go this route I can save a moderate amount of cash, but will I get nearly as much bang for the buck? I will be building a manifold toe distribe the air/gas mix to two burners. The air source will be about 4 feewr away on the floor, blowing directly into 1 1/2 inch pipe. I want to place a 1/2 inch black iron pipe sleeve about 4 - 6 inches above the blower, place a 3/8 inch x 6 inch sleeve into the pipe with a cap on that drilled out to 1/16 inch for the gas to pass in for mixing and distribution. There will be 2 elbows on the main piping then into the manifold where it will be distributed to the inlet to the forge.

My other question is will this setup quickly and easily get above welding temperature in a 20 in x 9 in x 8 inch forge, lined with 2 inches rigidized Kaowool covered with 1/2 inch of Kastolite 30, then a thin coat of Plastix 900f ceramic coating.

Any answers, advice or suggestions will be greatly appreciated.

Thank you, Milton

Welcome aboard Milton. Glad to have you here. I don't know much about blown burners so I won't attempt to answer that question, but the description of your forge body seems good. I'd expect to get to welding temps with a pair of good burners.

This is a worldwide forum and we won't remember that you're in Alabama outside this post. We recommend that you edit your header and put your location there. Also, if you haven't already, please read the pinned "Read This First" topic for tips on getting the most out of this forum.

Brian

Good Morning Milton,

There is no best design for a Forge, there always are compromises. The best Forge design depends on what you are using it for. I have over 14 Forges and they all are good for what I want each one to do.

My 'Go To', is an Induction Forge. Very quick Heat, almost no Scale. When you figure in Fuel costs, the cost of operating an Induction is least expense over a short period of time.

Neil

Forge lining sounds good, but how hot things will get all depends on a lot of variables that you don't give us:

1. Blower size and configuration (ideally you want a blower that is pressure dominant rather than volume flow - radial fins, not squirrel cage). You need to know the fan curve (flow and associated pressure for a couple of points) to properly evaluate. If you figure out the planned BTUH per burner head connected, you can calculate the gas and associated air needed. For a forge like you describe I would expect you to need at least 150 MBH., but hard to tell.

2. Burner piping configuration, in particular the specific location of the planned reducers and the location and orientation of the elbows. Personally I would not reduce the mixing chamber until after the manifold (where you connect the burner outlets) unless you have a particularly high pressure blower.

3. Type and pressure for your fuel gas (some like myself, admittedly very few, run residential pressure natural gas - very big difference from commercial pressure or propane).

4. Regulation methods for both the air and gas

5. Doors!!!

6. Is 20 in x 9 in x 8 inch the inside dimension or the shell? Kind of a large forge, why do you need one that big? Planning on architectural work? Do you already have a power hammer and/or striker?

Brian, Thnk you for your suggestion, I had not considered this being a world wide forum. I will attempt to put my location in the header while on here tonight.

Thanks again. Milton

Thank You Neil, I use my for primarily for knife making. Some of them are kind of large like machettes for choping brush, small limbs, and other similar purposes. I will eventually get into making swords or some type, but my skill level is not there yet. Soon I hope. I am hoping to build a second forge sometime over the next year, but not right now. I am building inventory at this time.

Thanks for your reply,

Milton

Latticino, Thanks for your reply. I am planning to use 1 1/2 in pipe from the blower to the manifold, with the forced air coming from a squirril cage blower, somewhere between 200 and 300 CFM's. I will reduce down to 1 inch after or at the manifold with each burner having a dedicated flow control ball type valve. I am hoping to take it down to 2 burners with the forced air. The inside of my forge winds up being 20 x 5 x 4 inches after all the refractory and other insulation. I am planning to round off the top corners to allow for a circular effect on the flames once they come in from the side. I do not know, but am hoping to be able to get the needed 75,000 BTU from each burner once blown. I have a temporary door on the rear of the forge with fire brick and am considering adding a hinged metal door with Kaowool, refractory and ceramic to help hold and reflect more heat, On the front I have a fire brick that serves as a door I can slide open and closed as necessary. Today I took my compressor and the blow gun, placed the tip of the blow gun in the air opening at the burner input of one burner and for the first time I was able to get a very small dragon's breath that was light blue with only yellow tips. This told me that forced air was very important for my situation. I have a 250 gallon dedicated propane tank that has a regulator that the propane company and I have turned to to about 20 lbs pressure. I have that piped into my forge through 3/4 inch black iron pipe, although now I wish I had gone with 1 1/4 to 1 1/2 inch pipe instead. However, I am able to get greater than 10 lbs pressure at the regulator for the forge with the burners turned off. Do you think I am going to be able to get the needed BTU's with this setup as I have described?

Thank you for your input.

Miltonj

Lattico,

I missed responding to one of your questions. Yes I have a tire hammer with a 40 lb hammer and 1 1/2 hp motor. I also have a Coal Ironworks 16 ton hydraulic press that comes om very handy as well. I am not sure how regulate the air, I presume it will be with a reostat to slow or speed up the fan as needed. Inside the forge I have the second regulator 0 to 30 lb to control the main gas input at the wall. The reducer will be at the manifold going from 1 1/2 down to 1 inch. WIth only 2 burners I think this will work, but not positive. You thoughts on the matter would be appreciated. I am not familiar with the radial fin blower. Can you enlighten me on those. If that is what I need, I will certainly try to put it in my budget. Things and problems you have mentioned is exactly why I posted on here. I do not know how to calculate the anticipated BTU value nor the necessary BTU's to obtain the level of heat I need. Currently my forge is woefully inadequate for what I now need, which is why I am upgrading. I just do want to find I screwed up and did not accomplish my goal of rapid preheat, timely material heating to forging temperature and forge welding temperature as needed.

Once again, thank you for your input.

Milton

13 minutes ago, mwyatt1955 said:

Latticino, Thanks for your reply. I am planning to use 1 1/2 in pipe from the blower to the manifold, with the forced air coming from a squirril cage blower, somewhere between 200 and 300 CFM's. I will reduce down to 1 inch after or at the manifold with each burner having a dedicated flow control ball type valve. I am hoping to take it down to 2 burners with the forced air. The inside of my forge winds up being 20 x 5 x 4 inches after all the refractory and other insulation. I am planning to round off the top corners to allow for a circular effect on the flames once they come in from the side. I do not know, but am hoping to be able to get the needed 75,000 BTU from each burner once blown. I have a temporary door on the rear of the forge with fire brick and am considering adding a hinged metal door with Kaowool, refractory and ceramic to help hold and reflect more heat, On the front I have a fire brick that serves as a door I can slide open and closed as necessary. Today I took my compressor and the blow gun, placed the tip of the blow gun in the air opening at the burner input of one burner and for the first time I was able to get a very small dragon's breath that was light blue with only yellow tips. This told me that forced air was very important for my situation. I have a 250 gallon dedicated propane tank that has a regulator that the propane company and I have turned to to about 20 lbs pressure. I have that piped into my forge through 3/4 inch black iron pipe, although now I wish I had gone with 1 1/4 to 1 1/2 inch pipe instead. However, I am able to get greater than 10 lbs pressure at the regulator for the forge with the burners turned off. Do you think I am going to be able to get the needed BTU's with this setup as I have described?

Thank you for your input.

Miltonj

Latticino,

I missed responding to one of your questions. Yes I have a tire hammer with a 40 lb hammer and 1 1/2 hp motor. I also have a Coal Ironworks 16 ton hydraulic press that comes om very handy as well. I am not sure how regulate the air, I presume it will be with a reostat to slow or speed up the fan as needed. Inside the forge I have the second regulator 0 to 30 lb to control the main gas input at the wall. The reducer will be at the manifold going from 1 1/2 down to 1 inch. WIth only 2 burners I think this will work, but not positive. You thoughts on the matter would be appreciated. I am not familiar with the radial fin blower. Can you enlighten me on those. If that is what I need, I will certainly try to put it in my budget. Things and problems you have mentioned is exactly why I posted on here. I do not know how to calculate the anticipated BTU value nor the necessary BTU's to obtain the level of heat I need. Currently my forge is woefully inadequate for what I now need, which is why I am upgrading. I just do want to find I screwed up and did not accomplish my goal of rapid preheat, timely material heating to forging temperature and forge welding temperature as needed.

Once again, thank you for your input.

Milton

On 5/29/2026 at 10:14 PM, mwyatt1955 said:

I live in Southeast Alabama near the Florida Line. I started forging about 5 years ago and need to upgrade my forge. I am hoping to get some sage advice from folks who know much more than I do about this topic. In essence, what I am wondering is should I simply upgrade my venturi burners to forced air and move them to the side of the forge body rather than on the top. If I should go this route I can save a moderate amount of cash, but will I get nearly as much bang for the buck? I will be building a manifold toe distribe the air/gas mix to two burners. The air source will be about 4 feewr away on the floor, blowing directly into 1 1/2 inch pipe. I want to place a 1/2 inch black iron pipe sleeve about 4 - 6 inches above the blower, place a 3/8 inch x 6 inch sleeve into the pipe with a cap on that drilled out to 1/16 inch for the gas to pass in for mixing and distribution. There will be 2 elbows on the main piping then into the manifold where it will be distributed to the inlet to the forge.

My other question is will this setup quickly and easily get above welding temperature in a 20 in x 9 in x 8 inch forge, lined with 2 inches rigidized Kaowool covered with 1/2 inch of Kastolite 30, then a thin coat of Plastix 900f ceramic coating.

Any answers, advice or suggestions will be greatly appreciated.

Thank you, Milton