Hi yall, I'm in the process of building a gas forge, it's from an old air tank, I'm kinda stuck on the burner design, I'd like to make my own or possibly buy some, I've been in contact with Larry zoeller about his z burners, but he's hard to get ahold of. I'm wanting a general purpose forge, but at the same time, I'd like to be able to forge weld in the future, so I think I would need 2 burners, any advice on construction would be greatly appreciated. Thanks

Have you read through the other posts in the gas forge section? There's plenty of good info in there including discussions about burners. Do a search for the 't burner', it's about as simple as you can get and works like a charm. As far as how many you need, you won't know that until you have your forge insulated and then you have to figure out your volume. 

The overall dimensions are 18"long x 10", I know I'll have to line the inside with 2" of ceramic blanket, would it be easier to do with 2 layers of 1"?

I'd definitely do it in 1in layers cut to fit snug that way it'll minimize wrinkles and it'll end better hold itself while waiting on its coating. What are you planning on makin? Dependin on what you're makin you might wanna consider 3 layers just to bring the volume down a little more which will sve on gas since you're not heating wasted space. I'm far from an expert on gas but I'm sure some of our old gassers will be on later and can give you much more help than I. 

BTW if you add your general location to your profile you might find someone here lives within visitin distance. As it stands right now I'll assume you live in the US but several of our guys are from many other corners of the world and they might assume you're in their back yard.

Thanks! I updated my info. Do u think   I should shorten it? 

Making it fit a common dimension of kaowool is a good idea, makes it easier to line and replace lining.  I've been using a shorter one for about 15 years now and pretty much never needed a longer heat.  Mine has a back door so I can heat stuff in the middle of a long piece; but *my* general smithing may not be *your* general smithing...

Thanks! I updated my info. Do u think   I should shorten it? 

That's why I asked what you're plannin on makin. Sayin you're makin a general purpose forge only says so much. As Thomas just said what you need and what I need for general purpose forgin may be entirely different.

If you do some reading in the gas forge section most of your questions are covered. The number of burners is determined by forge volume and burner size. The outside dimensions have nothing to do with much of anything but bench or stand space.

How to line, with what, kiln washes, floors, pass throughs, general shapes, etc. have been discussed at length. I'm in the process of editing a new set of T burner construction directions and am not going to write it a couple more times in advance. If you find the old drawings NO do NOT use lamp rod! That was a first time expedient cludge that worked, NOT a good jet mount.

Frosty The Lucky.

I guess what I meant by general is that I want a forge that I can forge and heat treat knives but at the same time if I wanted to forge weld, I'd be able to, I'd rather have more than I need. What are common dimensions of kaowool? Frosty, I looked for your t burner, I found the post, I wasn't able to open the pics. Thanks for the replies, this is all new to me

I guess what I meant by general is that I want a forge that I can forge and heat treat knives but at the same time if I wanted to forge weld, I'd be able to, I'd rather have more than I need. What are common dimensions of kaowool? Frosty, I looked for your t burner, I found the post, I wasn't able to open the pics. Thanks for the replies, this is all new to me

I may be pessimistic,  but I don't think you will be able to accomplish all three things in the same box.   Heat treat suggests careful control.   Welding is a another operation which requires a very different level of heat creation.    General forging is another classification and suggests that you have sufficient volume to permit the introduction of odd shapes in three dimensions.   A solid fuel forge does welding and general forging well.   Heat treating in a well controlled gas forge is often fairly even. You would be well advised to work on one aspect at a time.

Check out the attachments at the Forge Supplies page at www.WayneCoeArtistBlacksmith.com.

you can check the burner kits at www.hitemptools.com.

Do yall think it'll be ok to leave it the length that it is, once I put the 2" of ceramic blanket I'm gonna lose 4" in length. Should I cut a hole in the back as well?

you could put the back wall in the middle of the forge with a door in it

Do you know how to calculate the VOLUME of the forge chamber? volume and shape (to a lesser degree) are the things that dictate your burner requirements.

You need to do some of this stuff yourself you know.

Frosty The Lucky.

 

The way it sits now with no insulating material the volume is 1414 cubic inches(10x18") , if I account for the 2" of blanket it puts it at 6x14, with the radius of 3" and length of 14, it puts the volume at 396, doesn't sound right, so I would need 2 burners spaced about 6" apart

I'm thinking it's much smaller, around 260. But math has never been my strongest area and I get my formulas confused regularly. I think this one is 6*pi*14. But like I said I might be confused again.

  No, his math sounds about right, as long as he's going round.  Even a flat floor doesn't throw the numbers off by a whole lot.  I did a good bit of math for a twelve inch air tank similar to this one. For those in doubt the formula for area is r²pi (3²pi). Multiply by length for volume.  pi6(pi2r) is for circumference.  Multiply by length for surface area.

 The calculations for volume with a floor are obnoxious, involve some basic trig (which I hadn't used since high school), and might shave at most a third of the volume, unless almost half of the thing is floor, in which case you've pretty well nullified the purpose of a round forge body.

Ok, thanks for setting me straight, QuarryDog. I guess next time math is involved I'm gonna double check I'm usin the right formula before I say anythin.

I figured once I add the 2" of blanket material and the firebrick for the floor it should bring the volume way down, I've seen a forge similar to mine with the burners spaced out 5 3/8" apart. I've decided on 2 3/4 burners, built right they should cover 300-350 cu inches. Should I open up the back for a passthru?

A well tuned 3/4" burner is enough to bring 300-350 cu/in to welding heat. At 395 cu/in it's close enough with a single burner you can probably do it by turning the gas psi up. Put a split fire brick or kiln shelf in the bottom for a floor and you should be in range.

However it's pretty long so the heat will be uneven. Use two, 1/2" T burners spaced about like you figure would even the temp up nicely. Three 1/2" burners wouldn't be an unreasonable level of overkill at all.

Frosty The Lucky.

Thanks Frosty! On your t burners do u have choke plates on either side of the T

Is the construction the same for the 1/2 as it is for the 3/4, same mig tips?

Just throwin' my 2 cents in.  Wasn't aimin' fer toes.  I've been looking at building a gasser for a little while now,  I just can't seem to find a local pottery/ceramic/kiln/HVAC supply that I have easy access to and can/will help me, and I've even been being nice.  Even firebrick seems hard to come by.

  I'm a pretty firm believer in doing business locally, but I'm seriously thinking about going online.

 

I've never seen a t burner built like frostys that had any kind of choke. 

Pas far as the jet nozzle, they are different sizes I just can't recall and cannot find the topic it was just discussed a couple months ago if that helps any.  

I've been trying to find instructions on building one