Making Your Own Coffee Can Forge

Metalworking Workshop
Making Your Own Coffee Can Forge

Soup can, paint can, coffee can forge. Lots of people seem to think that casting and forging is out of their grasp, technically, financially, and in terms of the risks involved. Certainly getting deeply into smithing can mean all of that, but it’s really not that hard to create your own micro force for melting small amounts of metal for casting, knife forging, and the like.

If you do searches on “coffee can forge” and “micro forge,” you will find all manner of small forges made from little more than a tin can (scaled to the size of forge you want to create) and a “refractory lining,” a thick thermal mass inside the can for building up the high heat required to melt metal. Here are a couple of examples of relatively quick, easy, and inexpensive forge projects for you check out.

Coffee Can Forge

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In this video, YouTuber “clkindred” builds a simple propane forge out of a #10 steel can and a homemade refractory lining comprised of Perlite, sodium silicate, plaster of Paris (which is used here as an accelerant). After testing out the forge, he also finishes it up by sealing the Perlite lining with a special cement mixed up from sodium silicate, aluminum oxide abrasive (used in sand blasting), and magnesium silicate (aka baby powder).

Paint Can Forge

tinCanForge_4In this follow-up project, clkindred creates a bigger forge using a paint can as the form. Perlite, sodium silicate, water, aluminum oxide are again used, as is the formula for sealing cement: sodium silicate and aluminum oxide. As he points out in the video, besides using this cement to seal the refractory lining, you can also use it to form and then flame-cure various shapes, such as using it to create a crucible for use in your new forge.

Brake Drum Forge

tinCanForge_1Another kind of common backyard forge is made from a brake drum. In this Instructable, member “asuka42227” shows you how he made a small coal-fired hobbyist smith forge using an old brake drum, a shower drain, and some common plumbing parts.

Build Your Own $30 Micro-Forge

tinCanForge_3Back in Make: Volume 18, we featured this project by Len Cullum on building a very inexpensive desktop forge suitable for use with a standard 14 oz. propane torch. With this project, instead of casting a refractory liner, fire bricks are used and fashioned into a rectangular forge on a simple threaded rod stand.

Have you built one of these micro forges? If so, we’d love to hear about it, see pics, and learn more about how you use it. Please post in the comments below.

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Gareth Branwyn is a freelance writer and the former Editorial Director of Maker Media. He is the author or editor of over a dozen books on technology, DIY, and geek culture. He is currently a contributor to Boing Boing, Wink Books, and Wink Fun. His free weekly-ish maker tips newsletter can be found at

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