Trying to figure out appropriate forge size for burner- any help appreciated!

Hello all,
I got myself a box of firebricks, and stacked them so that the area inside my little forge was 81 cubic inches. The only burner I have
right now is a plumber's style propane torch- and that's not likely to change until well after the holliday season, whether I'd like it to or not.
I'm guessing that the volume of the interior is just way too big for what I'm doing- it will heat a 1/2" bar to a dull red, but it's even slower than just holding the torch on it in the open air.
The interior dimentions as I've got the bricks stacked are 2" wide, 4.5 " high, and 9" deep. I've got a hole drilled at a approx. 30 degree angle (pointing slightly upwards, so the tank can sit nearly upright) in the center of one of the firebricks on the side. The firebricks are cheap fireplace liners from Menard's, 4.5" x 9" x 1.5".
There are some cracks where air can get in due to the roughness of the bricks, and after a little experimentation, I made an opening of about 1.5" x 2" on each end by laying a firebrick on each end. That seemed to work about as well as it was going to work- which is not very well, of course.
I'm sure there are some problems with the design that will be immediately apparent to someone with more experience, so I'm hoping one of you guys will have an idea of how I can tune this up a bit.
What I *can* do within my resources and budget is cut the firebrick to whatever size is appropriate for a propane torch forge, and make a metal box out of anything from 11-20 ga. 1018 or 301 stainless that the firebrick can slide into- I think I could also manage to get a second propane or mapp gas torch. hopefully, that's enough to get me going!
Any suggestions, and particularly info related to volume and vent opening sizes will be really appreciated. I'm sure I'll upgrade to something better with a real burner and that ceramic insulation soon enough, but I'm just messing around on a budget for now.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Ron Reil has some very good Rules of Thumb at http://ronreil.abana.org/design1.shtml#rules There also are a lot of ideas on how to build your own burner. A few pipe fittings and such and you can make your own burner I currently use a "pile o' brick" forge with a Zoeller side arm burner and it works well http://www.geocities.com/zoellerforge/sidearm.html It's taken me over a year of use to figure out what configuration I would like to have. I just keep moving the bricks around to suit me.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@mtforge.com wrote:

For sure the way to go nowdays, the internet wasn't going when I made my pOOpane burner. :/

Not my words but exactly my experience! :)
http://www.panix.com/~alvinj/furnace.htm
My stuff ain't setup for forging just for heat treating knife blades and springs. The lighter colored bricks are insulated firebricks and are light-weight like styrofoam. No kidding, I've held one in my barehand while one face of the brick was at-least-orange-hot and turned that face toward my face and felt like it about singed my eyebrows. :)
~$3 each as opposed to ~$.50 each for the other heavy firebricks.
The first time using the new insulated firebricks I just about "melted;)" the O1 tool steel utility knife blank!
Ok, not metled but it sure as heck got all wiggly and jiggily and droopy. :)
Way-past the arrest point that I was watching for anyway. :)
http://www.panix.com/~alvinj/burner.htm
http://www.panix.com/~alvinj/burnerhead.jpg
The "screens" are screwed into the threads :) and they just happen to be stainless steel... the material was picked up off the ground at my favorite scrap yard (catylitic converter type exhaust screen).
Since that picture I've screwed-in 1/2" pipe reducer bushings (with their own screens) right in on top of those 3/4" ones shown.
Slowed everything up and am getting better results in my heat treating of thin knife blades.
Alvin in AZ
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@XX.com wrote:

At the Seattle ABANA conference this summer, Hank Knickmeyer's demo was set up with insulated firebricks, but they bought too low a temperature grade. The bricks he put over the opening of his forge (a very hot forge) kept melting on him. Everyone was amused.
Steve
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Not much help now, but years ago - I suspect even now - they have bags of Alumina mix that you mix up your own bricks or lay out a flay tray...
That stuff handles high temp - where the yellow bricks of air don't last.
Don't know a trade name but a kiln supplier or fire brick seller knows or can order.
Martin Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Life; NRA LOH & Endowment Member, Golden Eagle, Patriot"s Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
Steve Smith wrote:

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, 2 Dec 2006 21:58:23 +0000 (UTC), snipped-for-privacy@XX.com wrote:

Anyone have a good online source for these? AFAIK, there are no pottery suppliers in my neck of the woods.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

What neck of the woods is that? :)
Got mine at a brick yard in dumb ol Tucson. :)
They had several to choose from, different top temperatures and different insulation levels. Mine are the most insulating and are just like (no kidding) the material inside the ceramic kilns. (was given a rusted out mess of a cermic kiln back in the late 80's)
I was at the scrapyard one day and a couple guys were removing fire bricks from one of those rotary-glass-melters they use to make telescope mirrors at the UofA. Another college threw his whole works away, they found out where and high-tailed it over there and began stripping it of the more valuable parts. :) The fancy bricks.
The bricks they were removing looked kinda like fused clear glass beads and the guys were telling me how similar they were to the space shuttle tiles etc. They gave me the distinct impression my bricks were "ho hum" bricks. ;)
They looked like "mutt and jeff". :) I recognized the short fat one right away from TV (Science channel) and later saw the tall skinny one on TV.
Anyway, insulated firebricks would be quick and easy to fool with but IMO, from what I've learned here, that isn't the best way to get something worth while for forging.
"batting with a coating, inside a metal container" -a.c.b
Cheaper and better both, right guys?
Alvin in AZ (not a blacksmith)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sun, 3 Dec 2006 06:41:02 +0000 (UTC), snipped-for-privacy@XX.com wrote:

West-central Wisconsin. I checked with the local brick yard, and they had firebrick in two sizes- 1.5" thick, and 2.5" thick. The thicker stuff was $1.60 a brick, so I am assuming (though I could certainly be wrong) that it is the heavy firebrick. They're kind of the only game in town.

That's the plan, a little way down the road- I'm just impatient!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
So Alvin,
Do you ship those fancy bricks?
Steve
snipped-for-privacy@XX.com wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Never thought about it. :) I guess I should call for their specs and prices and post it. :)
Alvin in AZ
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Alvin,
Remember, the Post Office has the 'flat rate Priority' boxes -- all you can stuff, up to 70 pounds, for $8 or $9 shipping. Two sizes of boxes.
Brad K.
snipped-for-privacy@XX.com wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
God I wish we had those in Australia! Everything goes by weight through national post and, by weight & dimensions though international :-(
Regards Charles
BradK wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

http://www.panix.com/~alvinj/furnace.jpg
The prices are...
"K23" (2300F) $3.85 and are the light weight and light colored ones shown.
Standard "heavy" firebricks (also seen there as the dark yellow ones) are $1.46 each.
"K26" (2600F) $5.00 and are quite abit heavier than the light weight ones and are the only other firebricks they carry anymore they've dropped -at least- two others since I bought mine. At that time the K23's were $2.45 and the stardards were 75c (seems like).
I sure as heck don't know which type a guy needs for forging! :/ You guys tell me so we'll both know. ;) 2300F too low a temp for forging?

Meant to go by there yesterday and stood in Lowes parking lot thinking "what else was it I was wanting to do? :/"
Going by there I could have learned more about 'em like weights and other sources etc.
Anyway... how's those prices? :/
Alvin in AZ ps- my girlfriend is behind holding up the cardboard to hide all the other really "good" stuff I got, no she ain't naked, if she was naked I wouldn't have been bothering with pictures of my stupid pile of bricks!
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
K23 = 2300F K26 = 2600F K28 = 2800F K30 = 3000F (I want these)
snipped-for-privacy@XX.com wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Well...that sounds like new prices to me for standard firebrick. I'm reasonably sure 2300F would be a mistake. I don't know about the 2600F bricks; I've always used 3000F bricks.
Thanks for checking, but I think I'll pass.
steve
snipped-for-privacy@XX.com wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I'm completely devastated. :/
Trevor and Steve are soooo stinkin mean! ;)
Alvin in Dispair
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Some guys gets all of the breaks!
Martin
Martin H. Eastburn @ home at Lions' Lair with our computer lionslair at consolidated dot net TSRA, Life; NRA LOH & Endowment Member, Golden Eagle, Patriot"s Medal. NRA Second Amendment Task Force Charter Founder IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com /
snipped-for-privacy@XX.com wrote:

-
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Sat, 02 Dec 2006 23:43:56 -0600, Prometheus

I used Bailey's. http://www.baileypottery.com /
Pete Keillor
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
http://www.geocities.com/zoellerforge/flare.html A fine person to do business with.
Steve
Prometheus wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Howdy,
I would suggest carving 1 brick and make a 1 brick forge until you're ready to step up to a larger capacity. Considering you've only got a plumbers hand torch.
If you do this you will definitely be able to get started.
Regards Charles P.S. 9 x 1 is a recommended ratio of bore to length. P.P.S. JTH-7 Bernzomatic Hose Torch
Prometheus wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.