How to Build a Better Forge

Introduction: How to Build a Better Forge

How to build a better forge.

This forge is better insulated than the firebrick forge and keeps a more even heat on the inside.

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    34 Discussions


    11 months ago

    Erm... I'm looking to make a forge. I don't know a lot about the materials and know that some of them can be harmful. So I looked up whether or not dura blanket kills you upon skin contact and couldn't find anything. It seemed a bit extreme of a reaction and am wondering how accurate your statement is about it being fatal? And also if you are just making that up in a joking way it's misinformation like that which can end up actually killing or injuring a person when they don't pay attention to actual safety information because they think it's a joke. There was a point where you didn't know anything and not everyone understands these jokes as being obvious like the old skyhook and board stretcher stuff. They could easily treat actual safety precautions as a joke and give themselves cancer or blow something up. Don't joke about stuff like this. I got exposed over a period of weeks to friable asbestos and lead due to improper safety warnings, what may have seemed obvious to people in the industry isn't to amateurs I had no idea what I was opening myself up for. Don't do it. And if it is as deadly as you say I find it odd that I can't find any information on something that can cause death upon contact.

    I am assuming what we call Rock Wool in the US would do a good job as well, and handle higher temperatures as well...

    Brilliant work, I may build this and use Rock Wool and some high temp fire brick. if I do, I'll post a note about how it went.

    I used to work for a company that built, repaired, and maintained smelting, heat treating, and glass furnaces. Whenever we used that type of ''blanket'' for insulation, we would first soak it in AP green mixed to about the thickness of soup. That should make it a bit safer to handle, and maybe even cut down on particles floating around when in operation.

    1 reply

    How long should it typically take from ignition to get a piece of blade steel to red hot?

    i used fire cement instead of fire blanket. its rated to 1300 C . Outher shell is small fire extinguisher.


    Beautiful! I was talking to my uncle the other day about gas forges, weighing the pros and cons vs a coal forge like the one he has, and the larger working area for popping odd shaped or larger bits into the fire for heating seemed to tip to the coal forge. Leaving both ends of yours open means a long piece can be slid through until the appropriate spot is in position for heating, which is definitely a major plus. Little small maybe, but it's definitely an effective little heater.

    I don't like it. I'm sorry, but I get the fun out of Forging things by actually having to Screw around with the coal and other stuff. I am comfortable with it also. Don't flag me because I am just trying to make my... Unless! You could possibly set it up on a REAL forge and then you can use that as a Back/Front fire! Ooh! Yeah! Sorry I am Really Exited!

    1 reply

    This IS a "real" forge. Coal fired forges are more accurately described as "traditional". Don't knock it if it heats the metal properly. I work a cast iron coke forge myself, but I respect gas forges as a legitimate option for working metal.

    Could you replace your special durablanket with fiberglass insulation if you burnt off its resin binding agent before hand, and could you just use normal refractory cement instead of the ceramic stuff?

    "i know fiberglass insulation is toxic wen burnt"

    1 reply

    In my experience, that only works if you're willing to take the time to replace the insulation material every other day or so. If you use your forge as much as I do then you better be willing to take the time to do so. HOWEVER, if you have enough time and a large amount of unused insulation, go for it. That's what do to avoid spending a bunch of money since I only use a small forge and have a HUGE block of compressed fiberglass insulation from when my grandparents where repairing hail damage.

    I read somewhere that it is very dangerouse to try cutting a propane tank. Even if you think all the gas is out. How can I be sure this wont explode?

    2 replies

    I welded on a 300 gallon tank, I filled it up with water first and then drained it. No worries for sure after that.

    propane is heavier than air. If you want to be ultra safe, drill a hole on both ends and tip it upside down.

    You should do a tutorial on video production. This one of the most clear, staight forward videos I have seen on Instructables.

    Great instructable. Like the recycling of a propane container and making the forge without special hole saws.

    Durablanket is a possible carcinogen if fibres are inhaled.

    The statement "Remember, If you touch durablanket, You'll Die!" is a bit of a stretch. But you never can be too carefull.

    2 replies

    That propane bottle was pretty tough to get through. I admit to break several dremel bits before trying the tin snips. Ah the magic of video.
    Thanks for your comments!