Hi, Jon-

That forge looks like a beast <img src=' http://www.americanbladesmith.com/ipboard/public/style_emoticons//smile.gi f' class='bbc_emoticon' alt=':)' />. Let me preface my comments with the fact that I built a 2 burner venturi forge, not a blown one. That being said, I nearly built a vertical blown forge and asked quite a few questions about it. The best part is, there are a bunch of guys on here with a TON of good info on building good forges and will likely come give you a hand soon.

One of the reasons I didn't end up going with a blown forge was I couldn't find a blower that wasn't pretty expensive (a ways over $100.00). And from what I remember, I was told I would want one in the 130ish cfm range. As for 90 degree angles and such, I suppose if you had a way of making it a more gradual angle, that might be better, but I don't imagine necessary. I've seen plenty of forges that reach forge welding temps and the gas and/or air has to turn at least one 90 degree corner. If you don't mind my asking, what are you planning to use for the lining of your forge? You mentioned it'll be 3" in thickness-is it going to be kaowool or castable? I used kaowool and put some kiln cement refractory over it, then after I saved a few pennies, lined over that with ITC 100. I can say from personal experience, the ITC was well worth the money and has made a noticeable difference, both in how quickly it heats up the interior and how much faster my material gets heated. Although, with 3 burners and a blower, I imagine whatever you use will get piping hot in no time.

I'm sure the more experienced guys on here will be able to help you out with the mixing chamber and how many burner ports, etc. Good luck and I look forward to hearing how it all turns out.

Jeremy

Hi Jeremy, thanks for the response. I don't mind spending a little money on a decent blower, I'm likely to get a $500 grant for an arts festival to do a demo this year. It's a yearly thing and I got it last year to build a bronze furnace that worked out quite nicely. I'm actually using some refractory left over from that project. It's a plastic refractory that is rated for 3000 degrees. In the future I would probably go for castable over the rammable, if only for easy of installation. The result is the same. I've used castable in the past.

Hi Jon,

Check out this site www.dfoggknives.com/forge.htm. I've built several forges and burners using this design. All have reached welding temperature and I'm still using the first one I built. I did add a gate valve ahead of the blower to control air flow and I put a needle valve in the gas line to give better control of the gas. Hope this helps.

Dale

Hi Jon

I have forge similar to what you are building. I did mine with castable refractory and used a 6" piece of stove pipe for the internal form. I just have 1 burner with a blower of around 100 cfm if I remember right. The burner is horozontal coming into the forge body at a tangent to the top. The interior is 12" long and reaches welding heat with no problem.

As far as blowers, try www.surpluscenter.com - this is where I got mine.

Brian

Thanks for all the responses.

I guess at this point I have two concerns that I'd like to lay to rest before I proceed.

1) Is a single burner enough? The one I'm used to has 3, but it's been pointed out that they point downwards and heat the metal directly making having multiple burners more necessary. With the burner pointing to the side the heat is indirect, heats the whole forge, and therefor one is sufficient. Is this true?

2) Is a 60 cfm blower strong enough. I've heard 130, I've heard 50 or less, I've heard 40-100, I'm just not sure which is true. But I found this blower http://www.surpluscenter.com/item.asp?item=16-1404&catname=electric and it seems to be what I'm looking for, if 60 cfm is strong enough.

I'm using an 80 cu. ft. blower that I got from Surplur Center which is more than enough. I use a gate valve to control the amount of air going to the forge. I see no reason why a 60 cu. ft. blower wouldn't work.

Dale