Our club is offering a workshop this spring for building a gas forge. We only pay for materials and provide the vessel. The instructor is requesting that we email him with our plan so he can order the appropriate amount of materials and also so he can give feedback/revision suggestions if needed.

I've already reached out and asked him if I could make something like the NC Whisper Deluxe but with added end doors as well. He said yes. So now I'm looking at possible vessels and deciding if I need single (<=360cuft) or dual burners.

1. I'd love to be able to work on projects similar to the ABANA Curriculum Level II grill project using the gas forge. The problem I frequently run into is once I get a bar bent somewhere around 90-deg or a scroll larger than 3-4", it no longer fits into the gas forge and I have to switch over to using solid fuel. Thinking if I had a forge that could open on the side, I'd be able to continue working on those with gas.
2. I'd also love to be able to keep that side door closed and use it front-to-back like most standard gas forges operate. 

Knowing those two things - do you think I can get away with a single-burner or do I need larger than 360cuft and dual burner?

 

Vessel options I have on hand:

• 10" x 10" x 1/4" square tube (plenty of length)
• Kiln? gifted to me that I never got around to finishing (see pic)
• Scrap 30lb propane tank (approx 12.5" diameter x 20" tall)
• Balloon Time Helium tanks (approx 9.75" diameter x 15" tall)
• bed frames for angle iron if I were to make a vessel using framed up fire bricks with doors hinged directly to frame. Side-opening door would have to be the length of a brick for ease of converting... maybe?

 

My backup option if the above doesn't pan out financially is to make a much smaller forge for doing things like icicle ornaments, punches, small hooks, etc which would use minimal gas compared to the Mr Volcano I currently use (also not huge but bigger than necessary for those littler things).

 

I'll be happy to see what I can do for you Shaina, we have a quiet New Years eave planned. 

What do you mean by "dual-function" forge? A forge melter combination or similar, maybe horizontal / vertical chamber, etc.? For very different functions they do neither very well.

Or do you mean a dual access forge? Wide side door with smaller through doors lengthways through the chamber? This would be more like a Whisper Momma. The Deluxe only has the main full length door in the side.

I haven't looked at the specs on the NC whisper forges recently enough to remember how many cu/in their volumes are. They're pretty much all 2 burner forges and IIRC they're comparable to 3/4" NA burners. They are GOOD burners I've been seeing them around for a couple decades and they haven't changed much if any for good reason.

I assume when you say 10" x 10" x 1/4" you mean it's 10" square with 1/4" thick walls. When I was buying structural shapes I would've ordered 10" square 150lb.+/-. We're not worrying about that, but you might want to buy more someday. If you start fabricating ask for the current steel standards book at the yard. It saves sooooo much time if you speak the same jargon, saves a lot of explaining.

Let's say you go with the 10x10 square. You'll want to put 1 layers of 1" ceramic refractory blanket and rigidize it. This WILL reduce the inside cross section dimensions of the chamber to 6" x 6", the length will determine the volume but with this cross section you'll want at least 2 burners or the chamber won't come to an even temp. 

Don't forget 1' of that square pipe is going to weigh around 150lbs. before you put hinges, legs, burner mounts, etc. etc. on it. 

Sorry, that's a long way around to say I wouldn't recommend the square pipe, It'd be a real BEAST to move around.

If you already have it the 30lb. propane bottle will make a good forge. It'll be lighter and easier to line. Making a full length closable door will be no harder than in the square pipe. The steel is thinner so you can use a light duty wire feed, flux core or gmaw. EZ PZ.

Most people build these on their side with end access. Usually one large doorway on one end and a smaller passthrough to heat long stock in the middle. As you've said the problem with this is not being able to fit anything in that won't go through the opening. A full length side doorway will make a big difference and a more useful forge. 

Have you looked at the Forges 101 section of Iforge? I know we lost a lot of the pictures in an upgrade some years ago but there were step by step threads with pictures and such about exactly what I'm suggesting. 

I have to be careful not to go off on a long ramble describing the hows and whys of things but I'd use the propane tank, it'll be faster, easier and WAY lighter. There will be issues but not bad ones.

Frosty The Lucky. 

 

Sorry, yes, I meant dual access. 

You assumed correct on all counts. 

I did consider weight of the square tube but figured if it was what worked then it would just be a more fixed in position forge, lol. 30lb sounds like the winner vessel.

I started to look through Forges 101 and to be frank, it's overwhelming. For someone who struggles with retention, 99 pages is a lot to get through. That is where I got the 360cuft spec. I'm not worried about the actual build (burners, lining, etc) since it's a workshop led by someone I trust with decades of experience.

I'll work out any other details with the instructor. Thank you Frosty for your helpful response!

It's my pleasure, I hope I didn't make it more confusing than necessary. 

One last bit of advice do your best to resist using a firebrick for the floor, they are more harm than good. Un fortunately it's the way it was done before modern liner materials were available and many old timers will only do it "how it's always been done."

On the upside it's easy to make it right once you get it home and we'll help. 

Enjoy the workshop and remember to pump the instructor for all it's worth. It's not often you have one on one help.

Frosty The Lucky. 

On 12/31/2025 at 11:56 AM, Shainarue said:

Our club is offering a workshop this spring for building a gas forge. We only pay for materials and provide the vessel. The instructor is requesting that we email him with our plan so he can order the appropriate amount of materials and also so he can give feedback/revision suggestions if needed.

So, how did the workshop go?

We built the burners at the March meeting. He had a funeral to attend the same weekend as the April meeting so we'll do the burner placement and insulation and stuff at the May meeting. 

Here's my vessel so far: 

https://youtube.com/shorts/mxdjxerRxjU?si=kTL5HU6ZfGmQMY8d

The photo appears--based on size comparison with your hand--to be made from a two-gallon cylinder with its ends removed. What you replaced them with would be of interest to others.

  The square opening in its side looks like you intend to install a ribbon burner?

It was a really old forklift propane tank. Cut off the ends and replaced with sheet metal ... Maybe 14 or 16 gauge. 

The square opening is actually on the top, and will serve as an additional use option. So it can be used traditionally from the ends. Or I can close both ends and open the top, for using similarly to how you would use a coal forge. Would come in handy when working on things like square corners for a grill or spot heating on a large scroll. I plan to add way to hold bricks on the top which I can arrange to control the opening size.

I'll definitely continue to update here as it develops.

Interesting.  It sounds like you may be planning this already, but it might be a good idea to set up the end doors so they can be closed completely (rather than leaving a port/vent that's always open).  That should help limit convection when you have the top port open.

Yes, both ends well have latches that can secure the doors closed

A lot of forges have openings in the doors so you can put the end (or even the middle) of a bar in without opening the door itself.  If you add those -- and I find them quite useful -- you should think about also adding a way to block them off.

I suppose I could change up the design to have a "plug" style door rather than a hinge. Or maybe just an easy drop in hinge style so the door is easily removed if desired. Hmmm

Also, just for transparency, this concept was inspired by this video. I liked the idea of using it like you would a coal forge, but I wanted to also be able to use it as a typical gas forge rather than have a single purpose forge.

https://www.facebook.com/reel/905941445287433/

There are lots of options.  You could leave a port in one or both doors and cut a piece of firebrick to plug it up when you use the top port.  Or just build and see what happens.  In theory you could have cold air entering through the ends and coming out the top with the exhaust.  But that might never happen in practice

Yes, their are lots of options; while deciding which one will work best for you, a simple brick stack in front of the forge opening can serve very well. It isn't as though the bricks will be wasted once you decide what kind of door system to install. Firebricks are endlessly useful. 

Curious if anyone can tell me if one configuration is better than the other - or suggest a different configuration. I assume I'll need to come up with some kind of brace to support all this?

Since I will sometimes have the top port open, I wanted to use copper tubing until it is well out of danger of a rubber gas hose being at risk. For ease of reference, let's label them "with loops" and "without loops" - even though there are other differences.

Assuming you'll be attaching a rubber hose to the shut-off valve at the bottom, I'd say the most important thing is to support the valve somehow, so the hose isn't hanging off the copper tubes. Apart from that, I like the "loops" version better, because there are two less sets of threads, and the loops will help relieve stress on the fittings if there's some flex in the system. But the other version should work fine too.

Thanks Mike! Cost was less than $10 difference so it really didn't matter cost-wise which configuration I used. I'll go with your recommendation

And yes, the gas hose will connect to the shut-off valve at the bottom.