thought on charcoal forges

Hello all,
Long time lurker, first time poster....oh that's so lame I just had to say it though.
So I made a small drop point utility knife that I need to heat treat(1095).
First I was going to use charcoal...then I played around with fire and an old file....then I started thinking about a 1 brick forge. It dawned upon me that I never let the coals get even and hot...that and a wet hole in the ground made things far harder than they needed to be. Should have bought a chimney with my lump charcoal.
I'm back to charcoal, I think it would be an easier and cheaper setup for me to make. Truth is, I might not use it for the one knife, let alone learn to forge others. I like the idea of charcoal too. The knife blade is about as wide as goddard's one brick forge too.
I'm thinking of a setup similar to a grill. Maybe a flower pot or bucket lined with homemade refractory.
The refractory would be stepped so a grill would fit in a few inches from the bottom. Charcoal goes on top of the grill. Some air holes in the bottom of the container with a tuyere. I was thinking a small bellows would be plenty for this setup....what do you fella's think?
Maybe the tuyere should come from the side and be level or underneath the coals? Like a japanese sword forge.
Matthew ohio
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When MatthewK put fingers to keys it was 12/17/06 6:41 PM...

If it's a one-off, I wouldn't bother with refractory.
Just how big is this knife?
- CW
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Carl wrote:

It's maybe 3 inches long and a little less than 2 inches wide. I filed it from 1/8 inch stock. The back is close to that and the edge is about 1/32 of an inch. Full distal taper hidden tang.
Matthew
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MatthewK wrote:

What would you use it for? if you have some specific application in mind the forge could be tailored to that use.

If i understand that right you want the grill inside a refractory container without refractory in the grill? That would burn/melt the grill in short order even if the charcoal goes on the grate.
A small bellows is plenty for a charcoal fire big enough to get 3-4" of steel hot.

For charcoal the tuyere should come from the side with a little space below it. The tuyere should be water cooled or maybe with a refractory nipple so it doesn't melt. There is a discussoun on the forums at iforgeiron.com and Don Fogg's forum site regarding charcoal forges.
any other questions.
ron
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r payne wrote:

Small knife making. Probably 6 inches or less. Maybe some very basic blacksmithing. I would mainly like to pound some shape into the steel before I file it away. :)

I guess grate would have been the better word. I was thinking about a refractory lined container, a grate sat on a shelf near the bottom of the container to hold the charcoal. Similar to a bbq grill.
On further thought, I guess I just need a trough with some air.

cool

Thanks for the advice, the refractory nipple sounds easiest. How would you water cool something like that?

Thanks, I scrounged Fogg's forum a bit. I'll check the iforgeiron.com one out later.
Other than that all I've seen is Tim Lively type setups explained on the net.

Thanks Ron.
Matthew
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MatthewK wrote:

Which is pretty much what I'm doing at the present. This links to my blacksmithing stuff. http://www.geocities.com/son_of_bluegrass/smithing1.html It isn't as detailed as a lot of others but may give you ideas.

My forge was a weber grill in a previous life. the grate is gone and the refractory is wood ash.

A jacket is welded around the tuyere to keep it cool. On my forge what I did was place a brick on either side and one on top of the pipe and the bricks extend (thus acting like additional piping) to the fire. I have to be carefull with my hand crank blower so I don't put so much air through to create and oxidizing fire or worse blow hot bits of burning charcoal out of the forge.

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MatthewK wrote:

You would think that, but it's not necessarily true. If you talk about HA (historical accuracy) then charcoal and coal is the way to go.
However if you talk about portability, and ease of use then it's the one brick forge, you get more bang (absolutely a poor word choice when talking about gas, but what the hey) for your buck.

If you want something to last then definitely don't talk about flower pots. A metal container like a stock pot or a metal bucket will be fine. Home made refractory is okay for low temperature stuff like re-melting aluminium, but forging requires a little better.
You can make a charcoal forge by digging a hole in the ground (I will assume you have the "$50 Knife Shop" and you did mention Mister Goddard). And a pipe sealed at one end with holes drilled along it's length.
If you want something a little more portable and still want to use charcoal :-
Then I would suggest getting a 6" diameter pipe 1/4" wall thickness, as long as you want (sword length if you like). Cut it in half length wise (so you can make 2 if you want to). This is the base of the forge.
Get a length of 1" pipe, the length to match your forge base plus 6" and an end cap. Drill 1/4" holes every inch. Screw on the end cap. This is your tue iron.
You will need 6 1/4" bolts (my brain isn't working, so you can figure out how long the bolts need to be), and 16 nuts. Drill two holes, and secure the tue iron to the forge base with 2 bolts and 4 nuts, with the air holes pointing up (duh). Drill two holes at either end of the forge base and attach the remaining bolts with 3 nuts each (guess what these are legs).
Finished. As an air source I would suggest a dust extractor or an old vacuum with a blow feature.

I think it should work, just as long as you don't use a terracotta flower pot.

Or like a traditional European side blast forge.
I made a wooden box forge with a side blast, worked fine.
I have a couple of questions for you.
Do you want to be mobile? Are you interested in HA? Do you want to make stuff and don't really care as long as you get results? Are you on a budget? What do you really want to make in the future, your ultimate goal?
Regards Charles
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Chilla wrote:

Good to know.

Yep! :) It's the book that after many books that at least got me to file I knife out of some bar stock.

Too much heat for terracotta?

I've never seen any visual references do this type.

Yes, but only because I don't have any kind of permanent "shop".

Not so much, charcoal just feels purer to me. Which is kinda silly considering where I'm at with all this. I like the off-grid I don't need no stinkin' civilization feel also.

Yep.
Yeah...I can't run out and drop money on a forge or a lot of tooling. I guess maybe $100 USD or less seems to be my budget for this.

Ultimate best case scenario goal....european two handed sword....kriss knives......nice vegetable cleaver. Pattern welded blades of course :)
Short term, paring knives, balisong, maybe a karambit.
So, considering where I'm at....a one brick seems like the better route. The only trouble, I'll have to order the firebrick online.

Thanks,
Matthew
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MatthewK wrote:

I like Wayne's style, "spend only what you have to, the rest is nice but not absolutely necessary". This helped me out a lot, you'd think after 40 years I'd have figured this out.

Definitely, you'll crack that pot in no time, and it will crumble away soon after that.
A flower pot is good to use as a small burnout kiln for investment casting, and this can only be done with the pot lined and covered in aluminium foil. The temperatures to do this operation are far less than forging.

Of course you have, you just don't recall at the moment. Every time you see a blacksmith in a movie, biscuits to donuts they're using a side blast.

All right I have some ideas.

Ah you want to be a tribal smith, got it.

Okay, this is the way for you to go, and you'll be hard pressed to spend more than $40 USD.
Either use the method I posted earlier, or make a wooden box forge.
The wooden box forge is a very old European design, and very easy to construct. It's a very tribal approach, and can be used for charcoal only.
The traditional construction :-
    Make an open wooden box, line the inside with fire clay, drill a hole in the side to act as a tue iron. Make sure that every piece of wood that comes into contact with flames is coated with fire clay including the tue iron hole.
My modifications to this design :-
    Instead of using fire clay I line the box with hard fire bricks, not the K series, but the ones you find in the bottom of a BBQ or a fireplace. I use fireplace cement to cover the exposed wood.
A bellows can be used to supply air (I made my bellows).

You will need reasonable tools to make damascus, gas or coal, it can be done with charcoal, but apparently it's like pulling teeth.

Easy enough :-)

Funnily enough you can make a pattern welded blade with a one brick forge, but you need a JTH-7 Bernzomatic Hose Torch to make it work well.
Regards Charles
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MatthewK wrote:

How good a scrounge are you? Got a wrecking yard handy? Think 18-wheeler brake drum. They're usually about sixteen inches across, about eight inches deep, made of high strength steel, have a big hole on center in the 'bottom', complete with mounting holes for a flange for the air inlet. Get a piece of four inch pipe at the hardware store, threaded for a cap, a Tee fitting, another short piece of pipe, and another cap.. Take one of the caps and drill 3/8ths holes in it in a pattern until you've got about half of the cross sectional area turned into holes. Thats your air in. Screw the cap to the pipe, screw this to the tee, add the other short run to the other side of the tee, and finish up with the other cap. The second pipe and solid cap are the ash catcher. Mount the air pipe in the axle hole with some sheet metal to fit, bolts for the lugnut holes are optional. Feed air in through the side of the tee from your bellows or other air source. Airflow is more important than pressure here, you don't need to go crazy. Find some good clay and make up mud to line the pot, lay it in about two inches thick, allow to dry in the sun. This is your refractory; it is considered expendable but since it cost you nothing that's okay. Make up some sort of stand to hold all this. Make it sturdy, brake drums are heavy and the last thing you want is for the rig to fall over in the middle of a run. Fill it with BBQ charcoal and light it off and let the charcoal burn out. This will bake all the remaining water out of the refractory. You're ready to go to work. I've used these, they work great for charcoal and coal. The refractory will degrade over time, but its easy to get out and replace. The biggest mistake that newbs make is not getting the fire deep enough. You want fuel under the work in quantity, you're not making burgers here.
Happy whacking
Charly
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Thanks for the advice.
Matthew
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