How to Make a Soup Can Forge




Introduction: How to Make a Soup Can Forge

About: I like turning boring things into awesome things! Usually on video.
The above video details the process I used to create a simple and inexpensive propane forge from commonly available materials. In the video below this forge is put to use for the first time making a small fixed blade knife.

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181 Discussions

I made one and I love it! This really got me kick started into black smithing, and I am now in an apprenticeship with a friend of mine. Here's a picture of mine. I used a longer can for longer pieces of steel. Ot fires great as long as you have the right blow torch head (spiral flame).

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3 replies

How long has your forge lasted? Any breakdown of the plaster yet?

How long does the propane canister last? I've not used mine for any extended period of time, and i dont keep track of how long I've used it. Could I hook this up to a large propane tank?


1 year ago

How Did you get the flame to get so big?

Would I be able to make a hole in the other end so I could heat longer peices of metal, or would that break the creation?

Actually search up paint can forge and there is a whole different instructable for a paint can forge, because I doubt the same method used here would work for a paint can, only because a single blow torch could not heat that entire space enough to be useful

my igniter for my torch does not have a button that stays pressed in when pressed in, and then comes out when pressed again. Is it safe enough to use tape to hold it in place, or should I find a different igniter?

Awesome instructable Dude!!! super simple! Hope you can write for me the composition of the plaster (i didn´t understand that part of the video, as english is not my first language) and the type of gas used with the torch. Best regared!

2 replies

50% plaster of Paris and 50% sand mixed to a thick clay consistency


made one for my shop class to use. Works good. Thanks

Cant get mine to heat

The only sand I could get my hands on was 50 lbs of play sand. After looking at this instructable again, I think I need a different type of sand, or more plaster in the mix. The forge doesn't seem to evenly heat, and the only place I could get any metal to turn red was right in front of the flame. Also, how long does it take to properly cure? Thanks.


2 years ago

on other videos they leave the tunnel the whole way through. would that be better? also why dont you just put a can in the middle while it sets then the hole would look allot cleaner.

How long should it take to get to max temperature on first use? Im trying to speed up the plaster/sand mixture drying but its taking a while

To the original uploader or anyone who has built this: what is the lifespan of the plaster when forging steel? I am building a forge to make knives and may also be doing some forge welding. Need to know if plaster+sand/perlite will be able to stand up to the heat.