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Making a 55 gallon drum forge


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#1 Todd Gdula

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Posted 12 May 2012 - 06:31 AM

I recently acquired a 55 G drum in good condition and will be making a HT forge. The lid is a "closed head" (attached by a folded over lip, not a closing ring) with two openings.

I have a couple ideas how to cut the lid off so I can re-secure it after lining the drum, but before I start making cuts I can't take back - any input on the best way to cut it so it can be efficiently and securely reassembled? Any thoughts on how you would reassemble also appreciated.

It's an old Texaco drum and appears completely dry, but I'll cut with a recip saw and with the plugs out, not a torch.

Thanks for any input!
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#2 Alan Longmire

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Posted 12 May 2012 - 06:43 AM

You and me both, Todd! My drum has no holes, and the lid has been cut so it won't reseal. I was going to use some kind of clamps or weld on some bolt flanges or something. You do need to remove the lid sometimes, after all. Mine also doesn't have a hole in the lid, but I was gonna bolt a floor flange on for that part.

It will be festive-looking though. It's bright yellow and was used to hold pear juice concentrate from Chile, so it's got Spanish writing in cheerful red letters. :lol:

I'd also like advice: How much Kaowool, what to coat with, baffles/hangers/interior furniture, burner, and so on. I'm leaning towards using a large pipe as a muffle, but then I'd need an extra exhaust hole somewhere...Wouldn't I?

#3 Todd Gdula

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Posted 12 May 2012 - 06:53 AM

Alan and I await the sage advice of our fellow forumites... :rolleyes:
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#4 J. Helmes

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Posted 12 May 2012 - 07:15 AM

oooo I am looking forward to watching this progress. A drum forge might be on my list of thinhs to build .

#5 Jesus Hernandez

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Posted 12 May 2012 - 07:43 AM

I will contribute what I know from using water heater tanks. These tanks are made of thicker sheet metal. I cut around both ends with a angle grinder cutoff wheel and invariably this releases the stress in the metal which will no longer be round but can be coerced later into a round form again. If I was smart and a good welder, I would cross brace a length of steel bar across to try to keep the shape. After cutting off both ends, I put down one layer of 1 inch refractory blanket. That is more than sufficient for this purpose. I forgot, I hang "V" shaped 1/4" wire from the top to serve as supports for the blades. I also have pieces of re-bar coming from the sides where I have cut notches in the re-bar to hold the blades as well. I use a 3/4" T-rex burner for it but I am seriously thinking (when I find the time to do so) to switch to a pipe burner. A baffle built like a tent over the burner entering at the bottom could help with unevenness but I have found that I don't need a baffle in mine. Although I need to play with the gas needle valve a bit to get it right. One lid is welded back on (tack weld if sufficient) but before doing that I cover the inside of the lid with the blanket. The blanket stays in place by friction and pressure, it does not need any attachment. The main entry lid get a hinge at the 3 o'clock position and a simple latch at the 9 o'clock position in case I need to open it as a door. The only times I needed to do so was when I HT a blade that was too curved for my 4 inch opening (a falcata) and when I accidentally dropped a blade inside and fell to the bottom. Oops.

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#6 Todd Gdula

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Posted 12 May 2012 - 08:43 AM

Thanks, Jesus. Huge help - the wheels are turning.

Right now I'm thinking I'll cut off the bottom, modify/make cuts in the top as needed, install the hangers/furniture, line it, and tack weld the bottom back on. I think I'll live dangerously and not make an access door - I think a dropped blade can be retrieved with a magnet.

It's gonna be fired outside, so I may not coat the wool (wear a mask), or, if I can find a good way to spray satanite I may do that.

All just thoughts for now, pending more input.

When I have a plan in place I'm happy with I'll start a new thread and post progress pics.
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#7 J.S. Hill

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Posted 12 May 2012 - 08:57 AM

Todd and Alan--here is my experience, hopefully some helpful insight on things I would change or do to begin with, and a warning to keep you alert using one of these wonderful cannons:

I made a new horizontal HT forge just a few months ago to deal with some larger swords I have on commission. It was based on the Fogg model on his website. I wanted to make sure I could exploit W2 to its maximum potential, so I needed something fairly consistent and controllable. The only advice I can give you will be my opinion and based on my experience with just this ONE HT forge--previously I ran the blade through the fire until I got it as even as possible, then quenched. So, your mileage may vary.

I began with a 60 gallon open-head drum (one opening w/ a flanged lid and ring), which would eventually be set on its side. I cut two openings in the door, one for a flanged-nipple to insert my burner and one port to put in the blade. My work-space kinda dictated my port and burner be on the same side. I made a very small hole on the bottom of the drum to insert the tip of my swords for them to "hang"--please note I ONLY do Japanese-style blades, so sagging was/is not an issue. I lined the drum with whatever (it was 1" thick 8# density fiber). I say "whatever" because it could be any "minimum", or just what you have available, and work fine for the temps. we're talking about here. I lined the bottom, sides, and lid and coated it all with a medium-thick coating of satanite (best use for this material). With the construction of the drum, I lined the bottom and lid, then lined the circumference of the walls of the drum--the fiber lining the walls mechanically supported the fiber on the bottom and lid. I cut the holes in the fiber for the lid before putting it into place. Keep in mind everything needs to be supportive when it is turned horizontally.

With this arrangement, the forge was difficult to light (powered/blown burner), stalled until it came to heat, and was sluggish. Nothing I did with the burner made it work better. The back wall opposite the burner(keep in mind the burner port was beneath the tang of the sword) was MUCH hotter and the smaller-density of the tip-end of the sword made that part of the sword come to temp FAR before the denser machi-area. I was stumped, but continued to play with the forge to attempt to work things out. I tried baffles, bag-walls, etc. to no avail. I decided it was not getting better, so I figured the only way to get the machi-area up to temp. was to cut a hole in the back (bottom) of the forge so I could extend part of the sword (the tip) out and heat the machi-area more effectively. What happened should have happened at the beginning: the extra draft/oxygen/exhaust of the new/additional hole made the biggest difference in the performance of the forge. It would now run more consistently, run at a lower setting (not burning full-blast), and was MUCH more even in temperature. Not to mention MUCH quieter because the bottom of the drum was not whole and couldn't vibrate and pulse like before from the draft of the burner.

So, to summarize my rambling on what I settled that worked--two ports for exhaust purposes, large interior space, no baffles, etc.

The way I use the forge now does not require a hanger. The kissaki of Japanese-style swords is much less dense than the rest of the monouchi. So I suspend the sword between the two ports with JUST the kissaki out the back port and about 2"-3" past the machi of the nakago inside the forge. When all this comes to critical, I pull in the kissaki except for the very tip (3/4"). In just a minute the temps even out and the kissaki comes to temp--the very tip from radiant heat. I then pull the rest of the sword into the forge for the last bit of soak (W2 needs a little soak, but not much), then pull for the quench. I set the forge to burn at 1 1/2 PSI, let the interior get even in temp, put in the sword, watch for non-magnetic/recalescence, allow for a small soak, then quench. I rarely have to adjust the forge during the process, but DO adjust for weather, etc. I have had good results twice from this forge on VERY large, VERY massive swords (3/8" thick at the shinogi-ji). It is actually really easy to use and has removed a lot of variables for me with my previous process. IF you can be responsible and safe, I recommend this style forge HIGHLY vs. running through the fire. Salts would, of course, be superior, if you can afford the start-up costs and maintenance. But for the investment cost, this is a very effective means to an end.

What would I do differently? MAYBE put the burner opposite the nakago-end (the wall opposite the burner STILL seems a bit hotter), definitely build a smaller burner (I honestly think a small venturi burner would be perfectly adequate), and a nice spark-ignition/pilot-light would definitely be safer for a forge like this. I drilled holes to put in a 1/4" iron rod half-way down the forge, but didn't work out how far to hang it, since with Japanese-swords sometimes have a pre-curve, but are always different. So, I don't know if a "hanger" would really be of help or get in the way with the variety of curvatures of different swords. I have left it alone, since the way it is now is working fine. Certainly with European-style blades, some sort of support would be necessary.

NOW, please keep in mind that what you have actually built is a giant cannon: Large gas-inlet. Small exit, even if there is one on each side. 60 gallons of vaporized propane. The blast from one of these can shoot a fire-ball about 9-12 feet, maybe more. Nice 2-3 feet in diameter. Would be cool effect on July 4th. I didn't keep my eyes open the entire time--I was busy ducking and burning, so excuse me if I didn't get an exact number. I did remember to roll. And crawl 30 yards to the water-hose to douse myself. I even turned the darn gas off before crawling away. My advice is to take a flashlight and small iron rod and check for blockages on all the inlets/outlets.

What lead to the incident: After I thought I had the bugs worked out and successfully HT'd a sword, I came back a month later to HT another sword. I looked in all the ports and thought it was safe to light. I turned on the air and lit the burner. It sounded normal for a cold-start--not burning really well, which is usual for a forge with an over-powered burner or one with too-small of a retainer nozzle--they don't burn well until combustion temp. inside the forge. What I didn't know is that, in the interim of forging cycles, something built a nest in my burner-nozzle. I am guessing dirt-dabbers, but can't be sure. The burner was struggling to burn INSIDE the nozzle tube, but much of the gas was leaking into the forge and getting past the combustion. After 4-5 min. of the forge filling with propane at 3 PSI, the fire in the nozzle tube finally burned through whatever was blocking it, igniting all that propane at once. Of course, it couldn't burn without air, so the ignition pushed most of the gas out the ports on either side, where it could ignite in a dramatic fireball. I was staring at the forge, thankfully about 10 feet away, but directly in the line-of-site of one of the ports. My injuries were strange. The burns were only mild, like a sunburn. But there was bruising from the concussion of the blast. Thankfully I was left with only minor injuries that healed. But I will never trust the Cannon, again. I now check EVERYTHING--every port, every nozzle, every orifice--both visually and with a small rod I poke all-the-way through to be sure. When I light it, I drop a lit-rag into the port--if ignition is not immediate, I stop, turn everything off, wait for the gas to clear, then try again. I am OVERLY cautious and will be from now on.

As far as using a closed-top drum, I would definitely TRY to find an open-top drum to ease construction. I work in the chemical industry. However, ANYONE could call around to the local chemical-supply houses and ask for an open-top metal drum. They will usually GIVE you one. 60 gallons is better because there is more room for complete combustion and evening-out of temperatures, IMHO. Cleaning them is the least of your worries, because they are so much easier to deal with than a closed-top drum, especially with the construction of ports, etc. If all you can get is a closed-top I would recommend cutting it on the barrel-wall about 3-4 inches from each end, cut your ports, lay your fiber in the ends and then rolling into the barrel-circumference, then welding the ends back on. Tack-welds would do. I would test-fire it before welding back together, since you need to get in there for adjustments, sometimes. For a way to slide it on and off without welds, you could roll up a section of expanded steel just the right ID inside the barrel portion to give you a flange to push the ends back onto. Then you wouldn't have to weld AND you could remove them when you want to make adjustments (which you will). You don't need much support/structural strength for the fiber--you could use expanded metal for the shell of these, as long as it is out of the elements and you coat the fiber to protect your lungs. As a matter of fact, I WOULD use expanded-metal before I dealt with a closed-top drum. But that is just me and my lack of time and patience with a reciprocating saw.

And Alan, with European blades (or anything straight), I think a baffle would be great. I thought about building essentially the Fogg HT drum forge with the addition of a thick-walled 4"-5" diameter pipe the full-length of the forge. You would DEFINITELY have to have an exhaust port or two above or possibly below the pipe. The idea would be to have the pipe come to temperature, which would even out the temp and the sword to be HT'd would come to heat via contact with the pipe and/or radiant heat. But this won't work with Japanese swords unless they are always made the contour of the pipe, or you have a huge pipe to account for any pre-curve and "holders" to suspend the blade so it comes to heat evenly, so I abandoned the idea for now. A really small burner would be best for these type forges, regardless the method of heating.

Hope that helps and was worth reading! Sorry it was so long. Some of it was before my first cup of coffee, so let me know if I didn't make sense or if you have questions / need clarification. I struggled for a while with this, so I am just hoping to help save someone some of the headaches and troubles I had. Maybe if they build on this experience, they will share so others can improve what they already do.

Thanks,

Shannon

#8 J.S. Hill

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Posted 12 May 2012 - 09:32 AM

Everybody likes photos. Here's a photo of my latest WIP done in my new HT forge:

DSC00508-1.JPG

Bizen-style Juka-Choji in nioi-deki w/ some nie on W2 from aldo. Temporary, polished-in "window", so you can't really see anything but the "hints" at what all depth is there.

Shannon

#9 Todd Gdula

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Posted 12 May 2012 - 10:36 AM

I didn't keep my eyes open the entire time--I was busy ducking and burning,


Hehe...

I have some 5" thick walled pipe - I may brain storm for a bit before I pull the trigger.

Shannon, thanks for taking the time for that detailed response!

Edited by Todd Gdula, 12 May 2012 - 10:36 AM.

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#10 Alan Longmire

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Posted 12 May 2012 - 04:25 PM

Yes indeed, thanks, guys!

I have used a 30 gallon drum forge, and it did not need baffles or hangers for the Maldon Foe seaxes. It is not, however, mine. :lol:

I did a langsax and a sabre/hangar blade in the old charcoal trench Wednesday night, in the rain and wind, running low on charcoal, and trying to keep the rain out of my oil-filled tube. Imagine pulling a 22" lansax blade (monosteel) out of a fire with the wind blowing the smoke and ash into your eyes, the rain getting your glasses all spotty, and knocking the tin lid off the quench tube with one hand while plunging the blade in with the other, all the while hoping that the drizzle was not enough to warp or crack the 9260 blade...

It was at that moment I determined I would do no more swords until I got off my rear and built the drum forge I've been meaning to make for the last eight or ten years. :rolleyes:

#11 Todd Gdula

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Posted 12 May 2012 - 04:58 PM

Some musings;

If one were to run a 4-5" diameter steel pipe through the forge, would that not obviate the need to have access to the inside of the forge, ever? (you'd need to be able to light the burner, but the burner could be removable, or otherwise ignitable from the outside)

Wouldn't the atmosphere (ambient oxygen, no flame) in the pipe cause a lot of scaling?

If the pipe had holes in it exposing it to the forge atmosphere would that not reduce the scaling?
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#12 J.S. Hill

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Posted 12 May 2012 - 07:00 PM

Some musings;

If one were to run a 4-5" diameter steel pipe through the forge, would that not obviate the need to have access to the inside of the forge, ever? (you'd need to be able to light the burner, but the burner could be removable, or otherwise ignitable from the outside)

Wouldn't the atmosphere (ambient oxygen, no flame) in the pipe cause a lot of scaling?

If the pipe had holes in it exposing it to the forge atmosphere would that not reduce the scaling?


You could always seal one end of the pipe and throw a handful of charcoal into the pipe to smoulder to reduce scaling. In the case of having a separate chamber for the sword, the only reason you might need to get in is to change or repair the lining. Holes in the pipe would negate some of the effect of it evening out the ambient heat. However, it could also allow you to control hot-spots, etc. I have thought about all these different variables. I even have a huge piece of thick-walled iron pipe. In the end, I went with a design that was easy and simple. And it works, so I don't plan to fix what ain't broken. At least not in the middle of production-cycles. However, it never hurts to attempt to innovate. I just wish I had more time and money to experiment. Let us know if you try any of these and how they work out. Good Luck!

Shannon

#13 Todd Gdula

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Posted 12 May 2012 - 07:16 PM

You could always seal one end of the pipe and throw a handful of charcoal into the pipe to smoulder to reduce scaling. In the case of having a separate chamber for the sword, the only reason you might need to get in is to change or repair the lining. Holes in the pipe would negate some of the effect of it evening out the ambient heat. However, it could also allow you to control hot-spots, etc. I have thought about all these different variables. I even have a huge piece of thick-walled iron pipe. In the end, I went with a design that was easy and simple. And it works, so I don't plan to fix what ain't broken. At least not in the middle of production-cycles. However, it never hurts to attempt to innovate. I just wish I had more time and money to experiment. Let us know if you try any of these and how they work out. Good Luck!

Shannon


Yep, as soon as I have time, I'll build it, document the build, and do a test run.
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#14 Alan W.

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Posted 23 June 2012 - 09:44 AM

Jesus:

Is the pipe in your forge (used to hold the blade) closed on the far end?


Everyone:

Is Rutland castable as good as Satanite for lining the forge?


Thanks!
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#15 Kevin (The Professor)

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Posted 24 June 2012 - 10:14 PM

Alan - last time I used my trench forge it was in January in CT. I had to dig it out of 3 ft of snow. It was snowing, and I felt like Conan. The oil had to be heated because it looked like vaseline.

I bought the digital, vertical kiln because of this. Holds temp within 5degF with the cast iron pipe for extra mass.

I didn't have room for one of these drums. I would have likely gone that route, instead. But, honestly, if you have the money, call Tim Zowada and get set up with one of the kilns. If not, build away. I am seriously limited to one bay of a garage, so a large oil drum was more space than I could spare.

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#16 Alan W.

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Posted 27 June 2012 - 12:35 PM

Do you think a 3/4" burner is enough for a 55 gallon HT forge?

I am looking at the Zoeller burner...
Henry Fonda was still throwing up before each stage performance when he was seventy-five. Fear of failure doesn't go away.

The warrior and the artist live by the same code of necessity, which dictates that the battle must be fought anew every day.

- STEVEN PRESSFELD
The War of Art

#17 timgunn

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Posted 27 June 2012 - 02:19 PM

I've only seen 2 of the 55-gallon drum HT forges. Both worked very well.

The first one was all-manual and had a surprisingly small burner; about 1/2" from memory.

The other used two cheap Chinese propane torches and a PID controller; the (very) small torch was the continuous pilot, with the larger torch switched on and off by the controller. I'm pretty sure the gas jet in the big torch was 0.35mm/.014", which should give a fair idea of the heat input needed; I normally fit a 0.6mm (0.024") MIG tip, which actually measures about 0.7mm (.028"), in a 1" burner. Half the gas jet diameter should mean half the burner diameter, so a 1/2" burner would seem about right.

I'd expect a 3/4" burner to work OK. It'll probably be running at quite a low pressure.

#18 Tyler Miller

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Posted 02 September 2012 - 02:06 AM

I'd like to offer my experience with getting things hot in a 55 gallon drum. I own this updraft raku kiln made of most of a 55-gallon drum (design details here ) that I fire with a 500K BTU hardware store weed-burner torch mounted in/on some firebrick(always light before putting the burner in place or you're making a bomb for yourself!!), the final shot shows the kiln without furniture:
IMG_0143.JPG
IMG_0145.JPG
IMG_0146.jpg

I got the drum brand new from a local shipping supply company--no mystery chemicals!. I used uncoated, 2-inch inswool HTZ held in place with ceramic buttons make of stoneware and nichrome wire(the same as kiln elements). If you can't make the buttons, just cut slices of soft firebrick and drill holes for the wire. I used the uncoated fibre because I've never seen a potter not use it. Everyone wears a respirator when cutting and installing the material, and you're supposed to be wearing a respirator when firing anyway because of metal fumes if indoors, but everyone just fires outside in a well ventilated area without a mask. I used the HTZ, because it better withstands the shock of me taking the lid off the kiln to pull pots for reduction and crackle effects.

I can fire to cone 05(1870 @ 27 F/hr, 1888 @ 108 F/hr, 1911 @ 270 F/hr) in under an hour and a half with pottery and I'd imagine I could get it to heat in under 20 minutes if I really pushed it--the opposite of desirable in pottery. I've never heat-treated in it, but I want to.

If you wanted perfectly even heat (and a pretty killer gas pottery kiln if you made the liner a bit thicker), I would use a dual burner setup with a downdraft exhaust in a full, intact barrel. To do so, I would make a central channel of brick to support a kiln shelf with four notches cut into it, two cut on either side of the channel to allow the burner gases into the kiln--the burners of course mounted on either side of the channel. I would cut the other two notches on either end of the central channel--one to let the hot gases in, the other to let them out into an interior chimney(soft firebrick and refractory mortar) along the interior wall that continues up and out of the barrel. A small hinged and fibre lined door in the roof or top/side would allow access for heat treat.

I dunno, just my thoughts...

Edited by Tyler Miller, 02 September 2012 - 02:20 AM.


#19 Todd Gdula

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Posted 07 September 2012 - 06:50 PM

I'd like to offer my experience with getting things hot in a 55 gallon drum. I own this updraft raku kiln made of most of a 55-gallon drum (design details here ) that I fire with a 500K BTU hardware store weed-burner torch mounted in/on some firebrick(always light before putting the burner in place or you're making a bomb for yourself!!), the final shot shows the kiln without furniture:
IMG_0143.JPG
IMG_0145.JPG
IMG_0146.jpg

I got the drum brand new from a local shipping supply company--no mystery chemicals!. I used uncoated, 2-inch inswool HTZ held in place with ceramic buttons make of stoneware and nichrome wire(the same as kiln elements). If you can't make the buttons, just cut slices of soft firebrick and drill holes for the wire. I used the uncoated fibre because I've never seen a potter not use it. Everyone wears a respirator when cutting and installing the material, and you're supposed to be wearing a respirator when firing anyway because of metal fumes if indoors, but everyone just fires outside in a well ventilated area without a mask. I used the HTZ, because it better withstands the shock of me taking the lid off the kiln to pull pots for reduction and crackle effects.

I can fire to cone 05(1870 @ 27 F/hr, 1888 @ 108 F/hr, 1911 @ 270 F/hr) in under an hour and a half with pottery and I'd imagine I could get it to heat in under 20 minutes if I really pushed it--the opposite of desirable in pottery. I've never heat-treated in it, but I want to.

If you wanted perfectly even heat (and a pretty killer gas pottery kiln if you made the liner a bit thicker), I would use a dual burner setup with a downdraft exhaust in a full, intact barrel. To do so, I would make a central channel of brick to support a kiln shelf with four notches cut into it, two cut on either side of the channel to allow the burner gases into the kiln--the burners of course mounted on either side of the channel. I would cut the other two notches on either end of the central channel--one to let the hot gases in, the other to let them out into an interior chimney(soft firebrick and refractory mortar) along the interior wall that continues up and out of the barrel. A small hinged and fibre lined door in the roof or top/side would allow access for heat treat.

I dunno, just my thoughts...


Thanks Tyler, great input. I'm going to get this done either just before or just after Ashokan.
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#20 Brian Madigan

Brian Madigan
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Posted 20 September 2012 - 02:31 PM

Do you think a 3/4" burner is enough for a 55 gallon HT forge?

I am looking at the Zoeller burner...


Hell yes. I have a 1", 3/4" and 1/2" side draft atmospheric burners. The 1/2" is sufficient for 1500 degrees.

I have been using my 55 gal. ht furnace for a few years. It's never needed more than a few modifications.
I cut the top lid off so I could get in and clean out any remaining motor oil. It's lined with 1" superwool (http://www.sheffield...p/tcsw607ht.htm)
Superwool is supposed to be safe without coating, but seriously who wants anything foreign in the air?
Kaowool __does__ need a coating, either thin satanite or some fine castable refractory cement.
Rutland's is not a good refractory cement, as it doesn't reflect much heat. It will bubble up and turn whitish, but its not a good reflector.
Mine is vertical with a 4" access hole/exhaust at the top and a big enough hole in the bottom for the burner.
I have movable bridge across the top with different length hooks for hanging blades. I either drill the tang or bend the tang into a hook so I can hang it from one of the hooks.
The lid is sealed by the wool on the lid forming a gasket with the liner wool on the side.
The wool is kept in place with stainless wire refractory anchors. These are similar to what you see here:
http://www.rai-1.com...px?CategoryID=4
But I just twisted my own wire and punched them through the drum in a few places. It doesn't need much, but it keeps the wool from slumping and moving around. If you use the forge horizontally, which I did for a while, I find the wool wants to slump off the top. So the anchors can be helpful.




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