I am about to build a longer & larger diameter forge, mine is just to small. It will be 24" long x 9" square (round in this case), I want to use forced air to conserve fuel and get better use of it. It will have 3" thick kwool to hold heat in. I would really like some experienced advice on this forge, I have never done one like this before.
Minimum Effort = Minimum Results every time
I have built several of them. There's was a lot of trial and error that went into mine. What I learned is that you dont want to build the burner over 10" long. Seems like the longer ones I built ended up cracking. You need to use Mizzou castable or an equivalent. You need to cure the castable as per the instructions. I use gate valves to control the air. You need at least a 125cfm blower. I usually build round forges but this last one I built it was square. I have a couple YouTube videos of different ones running. Here are a few pics of the last one I put together. You want to use some kind of solenoid valve in case you lose power. This square one I built. I have 2" of duraboard 1" of kawool lined with a 99% alumina castable refractory that is highly flux resistant. If you have questions I will do my best to answer. As I am not a professional and I an just sharing my experience. With a forge that size I would want at least 27 5/16" holes, the burner no longer than 9.5". The orfice needs to be around 1/16". The 1/16" orfice will give you greater control.
Here's another view through my welding helmet.
Here is my ribbon burner forge in an old water tank top. The pic is after I turned it off because the picture of it running was way too bright to capture.
The instructions on making a ribbon burner by John Emmerling can be found at this link: https://drive.google.com/open?id=15IeSu3SVMH0IjmDg8TeZLiyMy357LUXM
I followed these instructions almost to the letter. I used wooden dowels and drilled them out rather than use the crayons, as he shows. It's been working great. Gets to 2300*F in about 7 minutes with a 2" Kaowool liner. My forge is a little shorter than your 24" idea by about 8" I run it at 3.5 psi with a 50cfm blower.
Joshua States
www.dosgatosforge.com
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Question, has anyone had issues with the ribbon Burners cracking and falling apart after using them for a while? Mine is at the point now where i need to fully put it out and remake it. I am just wondering that is normal or how long they are expected to last, Maybe i didn't cure it long enough the first time.
Thanks
Josh
The only ones I have ever had crack is the ones I made over 10" long. The smaller wider ones I have made I haven't had any issues with them.
