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Rich A.

Brush burner forge?

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Ok, feed up with charcoal forge. to hard to get hot, messy, and the smoke is killing my eyes(and i work outside). Was wanting to know if i could use a 500,000btu brush burner to fuel forge? I plane to make a round tube forge to replace/complement my charcoal forge. Plan is to use a 14" section of hot water tank, 1" of Koa wool, some fire bricks for the bottom, and castable refractory cement with the burner coming in at a angle to swirl thru the chamber. What you think?

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I tried to fire a drum forge with my 500,000 Btu weedburner two weeks ago. Miserable failure. The crude "venturi" (I hesitate to call it that, it's more of a simple mixer system) of the torch tip will not allow the right mix in an enclosed space. I could get up to about 1100 degrees at best. Buy or build a real burner, you'll be much happier.

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Ok, were can i buy a burner for a tube forge? I dont want to invest to much more into this right now. Were could i get good plans? Anyone got a old one they want to get read of?

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Ok, were can i buy a burner for a tube forge? I dont want to invest to much more into this right now. Were could i get good plans? Anyone got a old one they want to get read of?

 

You can buy kits from Larry Zoeller (http://www.zoellerforge.com/) and Darren Ellis (http://www.elliscustomknifeworks.com/). You can also buy very nice burners from hybridburners.com (I have a T-Rex), but they're kind of pricey and you said you want to keep costs down.

 

Propane burners aren't difficult to build, and there are a ton of plans on the Internet. (You can start here: http://www.abana.org/ronreil/sitemap.html .) But it takes some time to sort through it all, and if what you want is a more or less plug-n-play solution, rather than the satisfaction of starting entirely from scratch (and learning some stuff in the process), I think you'll probably be pleased with a sidearm burner kit from Ellis or Zoeller. Your proposed forge sounds rather large for one burner, though. Try to keep it to 350 cubic inches or less.

Edited by Matt Bower

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should i look at side burners or tube burners? Like the Zoeller burners. Was looking at a Hybrid T-rex, man there nice, but they cost alot!

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There is a lot of traffic here on forge and burner design, a search will find a whole lot of info.

 

Are you planing a horizontal forge, or a vertical design?

 

The forge you have talked about is quite large, what are you forging?

 

Fire brick and castable give you durability, at the cost of burning more fuel. If you forge like me, 4-5 hours at a time, several days a month or less, you probably don't need the durability as much as fuel efficiency. If you are forging 8 hours a day, every day, a castable forge is probably what you are after.

 

Fan or venturi?

 

Here is a picture of the burner I use. It's all made from off-the-shelf black iron pieces, no fabrication is required (except for the fan mount, all fans are different, so the mounts are too) (BTW, fans don't need to be huge, I'm using a 100cfm fan and it has to choked down 80% or so, or it blows the burner out.)

 

The long tube is for the fan to mount to,

 

BrnrExp1.jpg

 

The short tube after the reducer goes into the forge,

 

BrnrExp2.jpg

 

Two different configuration using the same parts. Some people think the elbow contributes to swirl and gas/air mixing, I can't tell the difference.

 

BrnrT1.jpg

 

BrnrT2.jpg

 

SAFETY WARNING: Don't use galvanized pipe near the hot end of the burner, burning zinc is bad stuff, it will hurt you.

 

Here is my partly finished vertical forge from the last rebuild, about 2 years ago. I has two inches of Kaowool and about a 5 inch hot zone.

 

NF2.jpg

 

This forge is still in use, though I just got a better fan for it (it has a better mount, the fan is much the same). It has a thick layer of Satanite covered with ITC100. I have repaired the area around the door a couple of times, but other than that it hasn't needed much.

 

I hope this is useful to you,

 

Geoff

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should i look at side burners or tube burners? Like the Zoeller burners. Was looking at a Hybrid T-rex, man there nice, but they cost alot!

 

They all work. The parts for the tube burners are more expensive. There's also his Z-burner, which looks like it should work fine. And yeah, blown burners are dead simple to make with off-the-shelf parts. The blower is the hardest thing to find. (And that's not very hard.)

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Would a box forge be possible? I got fire brick arround, am now thinking a 9"x4 1/2"x4 1/2" chamber with the burner coming in the side. Probley going to buy a Z-burner and all the fittings. The burner cost just a little more than the parts, and less than the parts and tools to make it. Plus i get a known system(I usually make my own equipment). Is a ball valve and idler system needed?

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You really want a ball valve for safety; it's good to be able to shut off the gas quickly if something goes wrong. Idlers aren't necessary , but they do save fuel.

 

Of course a box forge is possible. Hard fire bricks are big heat sinks, though. They'll make your forge heat more slowly, and used alone they may limit your maximum temperature. If you do go with them, you'd still be best served by a layer of insulation outside.

 

I won't say that you can't bring the burner in the side on a box forge, but I don't recall ever seeing one like that.

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Geoff,

 

Thanks for posting your set up. What size is your internal chamber after the insulation and what size is your pipe into the forge?

 

I'm in the middle of building a Fogg style vertical forge with a blown burner and I'm trying to decide how big to make my burner inlet and how much insulation I need to get my forge body down to a reasonable volume. (The only pipe I could get my hands on is 10" diameter.) With 1" of wool and some satanite I'll end up with a 7.5" burn zone and with an 18" body I'll have about 680 cubic inches of chamber. Will a 1" burner tube work to get up to welding heat?

 

I've done a lot of searching and haven't found any rules of thumb for this.

 

We now return you to your regularly scheduled thread. :huh:

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with a blown burner it shouldn't be a problem i am using a 14" body with a 12" hotzone and was able to get it up to a welding heat with about 4psi of gas! next time however i am going to put an extra layer of wool in to take it down to a 10" hot zone.

 

~~DJ

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I have three forges. My "everyday" forge, the one I use for all of my knife forging is a vertical style, I think it started out as a 10 cylinder. I've got 2 layers of Kaowool and a burn zone about 5 inches. I don't do any welding in that forge, I could, but the short hot zone means that it's hard to get a long heat on a piece.

 

My welding forge has an 18 x 4 x 5 body, with a brick floor. I can get a nice solid heat on about 16 inches of steel. Since I use a power hammer to draw out a billet, that size works well for me. On the down side, it takes 20 minutes to get to heat, where my vertical forge is ready to go in 90 seconds. It's a tradeoff.

 

The third forge is my HT forge, built out of a 33 gallon barrel. It heats pretty fast, since it has no hard surface material in it, just Kaowool. But HT is all that it gets used for.

 

You should be able to get to a welding heat in what you describe, but it will have it's limits.

 

Would a box forge be possible? I got fire brick around, am now thinking a 9"x4 1/2"x4 1/2" chamber with the burner coming in the side. Probley going to buy a Z-burner and all the fittings. The burner cost just a little more than the parts, and less than the parts and tools to make it. Plus i get a known system(I usually make my own equipment). Is a ball valve and idler system needed?

 

A brick pile is the first kind of gas forge I ever saw. They are easy to build, and easy to configure for weird shapes, but they are not fuel efficient. Fire comes squirting out of every crack, and you have the usual problem with having to heat all that brick before you can do any work. A shutoff is a good safety, an idler can save you some gas, but I've never used one. I have quarter turn shutoffs on all of my forges.

 

Geoff

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thank you Geoff for showing your setup, i'm not ready to give up on charcoal yet ( i like playing with fire) but I think I'll build one like yours just so I have an option. What size propane tank are you using and how much time do you get out of a tank?

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I use a #100 lb tank. The BBQ tanks tend to freeze up before you get much more than about 3 gallons out of them, the big tank pulls right down to the bottom of the tank. It's hard to know how long a tank lasts. Measuring burn rate has been a subject of contention. My vertical forge runs at about 1 psi line pressure and then is regulated by the little brass needle valve from there. I hardly ever get above half open, so .5 psi to the burner. That is plenty to forge with. My welding forge needs 4-5 psi line pressure and then is dialed in by the valve from there.

 

I don't forge in long chunks very much (though that will change for a while when the press comes on line) but I figure a tank lasts 14-20 8 hour forging days.

 

Geoff

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that sounds pretty efficient

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Thanks for all the help. Geoff, i like your set up. I am going to look for some 8" black iron to use for my forge body, was just wanting to use stuff i got on hand, but if I'm going gas im going to do it right. Just to clearify, the Kaowool doesnt suck up heat that much, but firebrick does? I really want to get to welding heat. That is the goal of this forge. I could get a good working heat out of the charcoal forge, but the fumes and mess are limiting me(I live in a apartment and have to use a friends yard and garage). Plus i want to try some folded steel and damascus soon.

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All refractories, brick, castable, insulating wool, have a certain thermal mass. You have to overcome the thermal mass of the material (ie heat it up) before the interior of the forge is hot enough to heat the steel. Hard stuff like brick take a lot longer to come up to working temp, which means that you are burning fuel waiting for it to happen. In my welding forge, I try to have a couple of simple project waiting to go that I can work on while the forge heats up, which also slows the process some. You can really see this effect by letting your forge come up to your working heat and then stick a 5 lb stack of steel into the fire. The color will drop toward the red for a while as the forge tries to overcome the thermal mass of the steel.

 

The trade off in forge design comes when the durability of your forge becomes more important than efficiency. If you were forging 2 or 3 shifts 6 days a week, the startup cost of the forge hardly matters and you'd want a hard surface design. If you forge like me, a day here, three or four days in a row there, then the startup of the forge takes on more importance. You do want a hard floor in a welding forge. Molten borax eats through Kaowool really fast. For a long time I used a removable hard plate in the bottom of my forge, made out of a kiln shelf. When I wasn't welding, I would take it out, and the forge was much quicker.

 

Geoff

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Well, i conntacted Zoeller today to order a side burner for my forge. The price is hard to beat, but if i use it in a 4x4x10" chamber will it be to much? still looking for a nice section of 8" or or 10" tubing to use. Just use the bricks i got for know(there is even a link on his page to make one with brick), but its just temporary.

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It's amazing how hard it is to get that first enclosure for a forge built. I spent months looking for a pipe of just the right size to replace my brick stack forge. Never did find it. I eventually took a hobby welding class up at the local community college.. They pointed me in the direction of a local steel forming company who sold me a sheet of steel and were kind enough to roll it into a tube for free.

 

Once you get over that first hurdle, though, forge bodies seem to just appear from the world around.. I've got a pair of fork lift propane tanks that might some day become vertical forges (very carefully, of course), a couple of smaller helium tanks (the party size, about the shape of a bbq propane tank), 2 25 gallon steel drums (small heat treating forges?), a couple few 55 gallon steel drums (dunno, full sized heat treating forge, or maybe a burnout oven for casting bronze)..

 

I wonder if that happens with power hammers.

 

I think that (1) 3/4" burner will heat 4"x4"x10" very well. Watch out in the wind, though, venturi burners are a little tweaky since they pull air in from the surroundings.. the air intakes on mine are exposed to the wind and a good gust can take the atmosphere in the forge from rich to lean and back very quickly.

 

Well, i conntacted Zoeller today to order a side burner for my forge. The price is hard to beat, but if i use it in a 4x4x10" chamber will it be to much? still looking for a nice section of 8" or or 10" tubing to use. Just use the bricks i got for know(there is even a link on his page to make one with brick), but its just temporary.

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So, I havent heard back from Mr. Zoeller in reply to my wanting to order... Going to give it a couple more days cause I know how it can get. If i have to order from someone else, my question is are the hybrid T-rex worth it? Or should i get a ellis? Any other burners out there?

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