Jump to content
I Forge Iron

Number of burners


Recommended Posts

Hello all! I tried posting in "More stupid questions from a newbie", but got forbidden and couldn't edit, so I figured I'd post a new threat.

that thread, for reference: http://www.iforgeiron.com/topic/43355-more-stupid-questions-from-a-newbie


After reading through this post many times, I've realized I have a similar question to Cranky. Is it better to use one 3/4 inch burner or two 1/2 inch burners when you have a volume of ~350 cu/in? My design is using an old air tank, with a 10 inch ID, so 6inch ID with liner. I can cut it as short or long as I want, but I was planning on having it be 14 inches, with a two inch liner on the rear, so 12 inches long. With that, it's 339.29 cu/in. What are your thoughts on number of burners? Will it be "better" to have it evenly heated with two 1/2 inch burners?

Thanks for the help! It's been nice to read through all of these posts, seeing people with similar problems to me, ha.

My basic idea for a design, for reference:

http://www.arscives.com/bladesign/forge.tutorial.htm

however, I want a closed back, with a window similar to:

http://www.zoellerforge.com/simplegasforge.html

I am planning on using the Frosty T burner. I thought to use Zoeller's modified side arm at first, but I like the simplicity of the Frosty T.

I am mostly planning on doing smaller trinket work, such as steel roses, hooks, candle holders, etc.

I am also interested in being able to use the forge for crafting a knife, so I will need it to be welding temperature.

I'm not sure that I need an entire foot of depth, but I'd like opinions.

Thank you all!
~GG

Edited by General_Googe
Link to post
Share on other sites

Ahhh, I may have misunderstood something I read, I feel silly now. 

I probably don't intend on doing pattern welding. It's interesting to me, but I don't believe I want to design my forge with that in mind for now.

But I do want to be able to make tongs, which generally uses forge welding to attach the reins to a piece of square stock, no?

Edited by General_Googe
Link to post
Share on other sites

Welcome aboard GG, glad to have you.

A couple things about gas forges in general. Welding temp is sort of a general target temp, not a requirement. You can always turn down the gas for lower temps but it's kinda hard to crank one up beyond it's max output. So, that's the reason behind the rule of thumb of one 3/4" burner per 300-350 cu/in volume.

That would be a rule of thumb in the shape of the fire chamber has a lot to do with the shape of the chamber. A long narrow chamber will have a much more even temp with evenly spaced smaller burners so long as their output is in line with the chamber's volume.

For a sort of extreme example, take a look at ribbon burners. In essence a ribbon burner is a plenum chamber feeding a bunch of 1/4" burners.

A good way to learn what you need from a forge is to start out with brick pile forges. They're easily changed to suit your project and learning curve. They're really easy and relatively inexpensive to experiment with till you know your own needs.

A lot of guys use and like pipe forges but you're going to find a 6" ID is going to be kind of limiting if you want to turn scrolls, make shelf brackets, etc. Learning what you  like to do is part of the learning curve. If you don't step into the trap many of us have of trying to build the perfect . . . whatever right out of the gate. Yeah, I have my first propane forge in the shop but it hasn't seen fire in 25 years.

Frosty The Lucky.

Link to post
Share on other sites

I do like WayneCoe's forge on his page, but I'm wary to build a bigger forge, because I see "Typical new person, building a forge too big the first time", which is part of the reason I had this one so small.

I can't edit in my whole post, so lets try summarizing. Sorry if this seems brief, but I can't post anything longer.

Is there a good "general purpose" size that you've discovered? I don't want to ask you to tell me how to build it, but I would like to learn from your experience.

I know my general purpose isn't the same as everybody else's.

I think creating a brick pile forge would be a good idea for me, I just get really excited about doing things one way and have a hard time thinking of alternatives.

Please let me know if there's questions you think I should be asking. I'm very interested in learning, and love reading books. I have backyard blacksmith and Gas Burners for Forges, Kilns, and Furnaces so far. Any other suggestions?

Thanks again,

~GG

Edited by General_Googe
Link to post
Share on other sites

My interests are largely decorative. Examples would be steel roses, candleholders (I like scrolling them), wall hooks, or banana hangers. I like to do scrolls and I am interested in cage twists and similar work.

 

Some examples:
http://i.ebayimg.com/00/s/NDgwWDY0MA==/z/cBwAAOxy69JTESw8/$_1.JPG?set_id=880000500F

http://www.abbsart.com/images/blacksmithphotos1_050a.jpg

http://www.spaco.org/Blacksmithing/Hooks/Hooks7.jpg

https://s-media-cache-ak0.pinimg.com/736x/8c/03/c8/8c03c83e23dc4103d5fa066b5cb39992.jpg

I'm sure there's other things I'd like to do, but I'm a bit pinched for time.

Link to post
Share on other sites

One of the reasons that I have a charcoal forge is that gas forges are, as Frosty has emphasized several times, radiant ovens where the reflected heat does the work not the gas.

I got disenchanted with propane forges the when I was trying to straighten sections of  coil spring from a freight car,  ( It broke and landed in the siding where I work . The siding was owned and paid for by my employer :) )   For large bends I prefer to work out of a solid fuel fire,

Link to post
Share on other sites

I'm with Charlotte, A solid fuel fire allows for much larger work. But I do like the ease of a gas forge for smaller items.

I built my gas forge because of the extremely dry summer we had, and a project needed to get done. I didn't want risk any fire flies so I built the gasser. I will continue to use both my coal forge, and my gasser depending on the project at hand.

Link to post
Share on other sites

Thanks for the input, Charlotte! And thank you for the continued discussion, Thor.

I can definitely see using a coal forge, however, due to my location I believe that a gasser is better for my uses for now. Perhaps when I move out away from the city I'll be able to have the open fire. 

As per size, I am thinking a slightly larger version of what I have, possibly built from a steel sheet like Frosty suggests in other posts. Or perhaps the five gallon bucket design which Larry Zoeller has on his website. At any rate, I am thinking a little larger than the 6 inches, and am leaning towards more like 10. This should give me space to do large enough work, but not be super massive at the same time.

Edited by General_Googe
Link to post
Share on other sites

Fair enough, it may be a good idea to look it up and figure out about the coal forge. I'm still interested in building a gas forge to play with for now. I think it will be a good learning experience, and it honestly seems like it will be fun to make, too... I've got some thinking to do. Thanks again for the help, it's much appreciated.

Link to post
Share on other sites

I just finished building a 5 gal. air tank forge it has an interior area of 358 cubic inches with one 3/4" burner  and had some time to run the forge and check out some temperatures.
It took 3.25 minutes at 2 psi ball valve 1/2 way open to reach 1550 F and the same 2psi ball valve all the way open 7 minutes 2000 F
This forge build far exceeded all my expectation

PICT1002.jpgPICT1003.jpgPICT1005.jpg

PICT1008.jpg

Edited by KWJ
Link to post
Share on other sites

Looking good. What size is the gas jet? You should be able to run it with the 1/4 turn ball valve all the way open and do your heat adjustments with the regulator. Partially open valves aren't good things running propane. I can't explain it well but propane can cause erosion of the valve seats.

Needle valves are the exception but they're designed to operate with a restricted opening and propane.

If you're getting that clean a burn running 2 psig. I'll bet you could run a larger gas jet and put more fuel and air in the forge in a clean burning ratio.

However, I'm a "don't fix it if it ain't broke" guy and if it's working as well as it looks and you don't need more I'd call it golden.

Frosty The Lucky

Link to post
Share on other sites
Hello KWJ!
Forbidden edit again, so this is short, again.

I have a terrible time estimating size, would you please be able to let me know the dimensions of your forge? Also, where did you purchase the 5 gallon air tank from? 

Thanks for the post!

~GG

Edited by General_Googe
Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...