Author Topic: No forge and no oxy-act torch  (Read 811 times)

Offline tom coffey

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No forge and no oxy-act torch
« on: January 23, 2024, 11:29:45 PM »
For those of us amatuers who do not have either of the aformentioned at our disposal, I guess the next best thing is a Mapp gas torch.  I use one for a lot of things, even lighting the charcoal in our grill and a fire in our firepit. But for blacksmithing and metal working I have questions. I have looked for but have not found a good tutorial on using one. My questions are... how close to hold the torch to the work, how fast to move along the work when heating, what can vice and-or clamp jaws be lined with to avoid heat transfer from the work. Anyone know of a good article or video ?

Offline rich pierce

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Re: No forge and no oxy-act torch
« Reply #1 on: January 24, 2024, 12:04:55 AM »
Unless the work is very thin, holding in a vise is not going to work with Mapp gas. I am able to braze with propane by making a fire brick cubby and using 2 propane torches on pieces not more than 3/16” thick and not too wide. For example to make a trigger plate with a boss on it I use 1/8” thick mild stock and brass a short piece of 5/16 or 3/8” bolt atop it. Yes, I know solder will do for such work but brazing looks right for the period. I also braze seams on thin mild steel ramrod tips, brazing a solid piece about 3/8” long for the threads. I usually lay a few rods on the floor of the cubby to lift the work above the fire brick to really feel the heat.
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Offline Long Ears

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Re: No forge and no oxy-act torch
« Reply #2 on: January 24, 2024, 03:57:50 AM »
Tom, depending on how large your work is a mapps or propane will not work well for forging unless tightly contained in a brick oven. There isn't anything you can line tools with to stop that much heat from transferring. That's the reason for blacksmith tongs. For small parts I use the same needle nose pliers. It pretty much ruins them for anything else. Bob

Offline Justin Urbantas

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Re: No forge and no oxy-act torch
« Reply #3 on: January 24, 2024, 04:40:31 AM »
A forge is extremely simple to build. Something to contain fire, and Something to supply air.  A hole in the ground like a Dakota fire hole, and a hairdryer works. I've used an old bbq lined with mud. Charcoal, coal, wood all work for fuel.


Offline TDM

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Re: No forge and no oxy-act torch
« Reply #4 on: January 24, 2024, 05:42:16 AM »
Yep, made my first blade with a homemade charcoal forge and hair dryer, in fact, burned the tip off first try. With a decent air source you can do quite a bit with a charcoal forge.

Offline Clowdis

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Re: No forge and no oxy-act torch
« Reply #5 on: January 24, 2024, 04:29:14 PM »
Has anyone tried using an induction coil for small forging projects? 

Online Eric Kettenburg

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Re: No forge and no oxy-act torch
« Reply #6 on: January 24, 2024, 04:52:23 PM »
At least three of the old (post civil war through end of the 19th century) barns here in my area had *WOOD* forges in them.  Basically a large tray of @ 2X10s on legs, @ 4 feet square and filled with mud with a hole in the center and thin sheet metal air ducts.  One still had an old crank blower on a stand attached.  Seemed to work well for them, and dirt cheap (no pun intended) to make.  I don't know if they were using charcoal or bituminous coal.
Strange women lying in ponds, distributing swords, is no basis for a system of government!

Offline Elnathan

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Re: No forge and no oxy-act torch
« Reply #7 on: January 25, 2024, 09:27:38 PM »
I use firebricks piled on top of each other to trap/reflect heat from the torch. I also made a small, two-brick forge but it doesn't work well for me, probably because I put the hole too far back. I've hardened knives 5-6" long with a MAPP torch and a couple firebricks arranged on top of each other, but that is about the limit of its use.

For forges proper, charcoal works really quite well as a fuel source, as long as you don't leave the blower running when you don't need the heat, and if you use a sideblown air source doesn't require a valve underneath to vent ashes unless you are working a long time. That means the forge can be as simple as a hole in the ground, or a wooden box filled with clay or sand...I used a small version of a Japanese-type forge, just a shallow hole in the ground flanked by two walls made from clay, with the tuyere running through the middle of one wall.

Sideblown forges work well, but there isn't or at least wasn't much written about them, so it took me awhile to figure out the best place to put the tuyere and how to place the piece in the fire for best effect. Once I got used to it I loved it. What I didn't love was squatting in the ground to do blacksmithing! I'll make a raised forge next time.
A man can never have too much red wine, too many books, or too much ammunition -  Rudyard Kipling