I'm in the process of building a gas forge out of an old freon tank. I have the tank cleaned out and the opening cut, and used the handle off the top to make a base for it. So far so good. Now to line it with something. I was planning on buying kaowool to line it with, but recently saw a yotube video on the construction of a soup can forge. In the video, the guy lined the forge with a 50/50 mixture of plaster of paris and sand. Has anyone here had any experience with this method of lining a forge? Pros/cons?

PoP and sand is not an insulator regardless of what anyone says.  It will hold heat in, but only because the density slows down the rate of loss more so than a bare can does.  It's cheap, for sure, and there's a very good reason why professionals don't use it.

 

Use the kaowool and line that with some satanite and plistix or itc100.

It's way more expensive than kaowool!   Not the original cost but the extra fuel needed to run it.  Sort of like getting a "free" car that gets 8 miles per gallon.  In a year of commuting you could have probably *bought* a better car for what you paid for the excessive gas usage.

Thanks guys! That's what I needed to know.

Check out my tutorial at the Forge Supplies page on my web-site.

Check out my tutorial at the Forge Supplies page on my web-site.

Thanks! Good info.

Wayne's a good guy; a lot of my quad-state spending money went to him one year and I've never regretted it!

I picked up some magnesium oxide hardy board (it looks like sheetrock and is supposed to be the new replacement for hardy) from a guy that builds outdoor kitchens he said it will withstand 6000°F for 15sec. does anyone have any experience with this stuff? I was thinking of using it with refractory cement to build a box inside of my propane tank forge.

I can't find anything to support his 6000° claim. just a YouTube video with a propane torch somewhere around 600° at about 3"away for 15mins. everything else is just environmental impact and construction info.

As long as you don't do anything for longer than 14 seconds... this seems perfectly reasonable to use!

 

I picked up some magnesium oxide hardy board (it looks like sheetrock and is supposed to be the new replacement for hardy) from a guy that builds outdoor kitchens he said it will withstand 6000°F for 15sec. does anyone have any experience with this stuff? I was thinking of using it with refractory cement to build a box inside of my propane tank forge.

Flyguy8555, where are you located? maybe someone nearby can help you out... if we only knew whether we were nearby or not.

A log will withstand for 15 seconds.

my thought process was if it takes 15 secs at 6000°f with no effect other than soot. how long will it stand up to much lower temps. like that found in a single burner propane forge. sorry no more stupid questions.

Flyguy8555, where are you located? maybe someone nearby can help you out... if we only knew whether we were nearby or not.

I'm in North-Central Iowa - thanks for the reminder, I've been meaning to put that in my profile and keep forgetting.

Right now the bigger gas forge is on hold because my smaller forge is working sooooo well. It's made from 2 soft fire bricks - the design is copied from Paul Linden, my toolmaking instructor at North House Folk School (I don't think he originated the idea). I was having trouble getting it up to temp with my old propane torch, so I recently upgraded to a Bernzomatic swirl tip torch and an adapter hose so I could run off my bulk LP tank. As the saying goes, now we're cooking with peanut oil! It now gets up to temp fast and works great. the inside dimensions are 2 1/2" by 9". I use an old paving brick for a "back door", it helps retain heat, and to forge longer pieces, I just slide it out of the way.

The inner shelves and the stand are made from the same steel grating - so far it hasn't burned up. Paul had used ceramic rods in his forge - I used what I had on hand.