Double burner high pressure = slow heat ?

[Txcwboy]

Had a chance to use a buddies 2 burner store bought ( off ebay) forge the other day. First off, it runs at like 20 psi ? Seemed high to me for someone that only has used a 1 venturi burner Homebrew forge . Secondly, it didnt seem to be that hot. Took my 1/8 thick x 7" blade a long while to heat up and then it had to be straight in the flame. Doesnt have the vortec my 8 inch pipe forge does. It was a smooth texture ceramic liner insides. When I have my single burner working off 8 pounds , the entire inside was orange . It would really heat up fast. All in all, I wasnt impressed at all. Are they suppose to have to run at that high ? Shouldnt they get hotter quicker?

THANKS

Dave

http://cgi.ebay.com/ws/eBayISAPI.dll...lenotsupported

[Ed Caffrey]

Not trying to be a butthead, but now you know the difference between a poorly designed forge, and one that was properly designed.

I looked at the link you posted, and cringed. In my opinion, the only thing a forge of that design is good for is a boat anchor....or maybe a yard ornament. Everything about it is poorly designed...... at least for any Bladesmithing applications. You've been around long enough to remember all the conversations we've had on the forums about square design forges.....they are just plain inefficient. Next, anytime a burner points directly on the work piece, its trouble waiting to happen for the types of steels we use. The high pressure used is a compensatory measure to try to overcome the poor design...and as you witnessed, it doesn't work. If the burners were a larger diameter, and the gas orifice size increased slightly, the pressure could be reduced, but because of the design, it questionable if it would improve the performance.

Now that you've been exposed to that forge, you likely understand more about why I always try to steer people away for something like that when they post questions about buying or building a forge.

[B.Finnigan]

My very first forge I built was based on a vastly improved version of that type. It still did not work good for forging or HTing. I see the cost of that unit with shipping to my zip is about $362. I can build four of the forced air forge I am currently using for that much and still have money left over.

There is another dual burner venturi offered on Fleabay with the same design that would be an equal rip off to to buy and try to make knives with.

[Doug Lester]

I have come to believe that one can build a better gas forge for less money than any commercially made unit that I have seen out there. A blown burner is not that hard to make; it's easier than a venturi unit. If you have the equiptment that will allow you to drill and tap accurately, a venturi unit is not all that hard to actually.

Doug Lester

[Thingmaker]

Openings of the eBay forge are nearly 60 square inches when combined! That's about five times what I see on most forges. Have your buddy block them off with firebrick.

[Quickcut]

Ed I just read your post on sounding like a butt head and have had an interest in building or buying a forge . Where would be a good place to start. I don't want to think back and know I'm the butt head for jumping feet first and not asking the pro's before I build or buy a dude. This question has probably been beat to death before, so just stear me in the right direction.

[Txcwboy]

Quickcut, most people end up with more than one attempt anyways. Im working on my 3rd. But here is a basic idea. Use a large pipe and some Koolwool .

http://www.indiangeorgesknives.com/b...g_a_forge.html

Dave

[Wade Holloway]

Welcome Quickcut. You will find lots of answers to your question. Dave gave you a good start but if you just want to buy one instead of making one try elliscustomknifeworks.com

[AUBE]

That sounds like an exceptionally bad designed forge. I have a single burner square forge with hard ceramic liners and while it's probably not as efficient as the round forges it sounds a heck of a lot more efficient than that forge. I run it at around 4-5psi for heat treating and forging and at 8-10psi for welding damascus billets....usually 1"x1"x4-6".


It takes awhile to heat up due to the liner material, the wool type heats up much quicker, but once hot it works pretty well. I block off the back port with firebrick unless I'm working on a large piece. Also flux does no damage to the lining.

[Txcwboy]

Quickcut

THe Freon Can Forge is pretty popular and easy to build. Search here and the net for it.

Good Luck

Dave

[NJStricker]

Guys,

Our own Ray Rogers has a page on his website that discusses his build of a forced air mini forge. This is the general design I'm planning to build in the next couple of months.

http://www.rayrogers.com/miniforge.htm

[Quickcut]

Hey guys thanks for the advice. I didn't think one attempt would do it that's why I asked. I've read of many type's. But would like the first to at least heat decently. Again thanks I'll start gathering pieces.

[Doug Lester]

There are some of us that have about as much fun building forges as making knives. We make one and then see something that we think could work a little better so we make another (however, it is never to be said that we actually built one that didn't work ). Sometimes we see a forge design that looks so neat that we build it even though we don't need another forge, which is about like saying that you don't need another hammer .

Doug Lester