[TheForge] LP burner question.

[Dan Brewer]

Frosty's burner is real basic.  Mike Porter has designed burners that work
down to 3/8 inch.  The basic concept of all burners ifs to mix fuel and air
in the correct ratio and then get them to burn just at the end of the
burner.  So a 1/2 in burner you will need a black pipe about 10 inches long.
Cut the threads off one end so you only have threads on one end.  You need a
bell reducer 1/2 to 1/4 pipe.  This goes on the threaded end.  Your jet will
be a 1/8 inch pipe 5 to 6  inches long.  On one end solder in a 1/2 inch
long piece of copper tubing.  Drill and tap the end for M6 or 1/4 x 20.
This is determined by  the mig contact tip you get.  You will want a .024
tip that is tapered and 1 inch long.  If you can not find one look on Larry
Zoller,s web page.  You will need to drill and tap the bell reducer to
capture the 1/8 pipe.  Depending on the quality of parts you have you might
have to drill out the bell reducer a little to fit the pipe in.  On the 1/2
in pipe you will want to make two slots about 3/8 inch wide and 2 1/2 inches
long.  The slots should start just where the  bell reducer stops.  I use a
drill to locate the ends of the slots and a die grinder to cut the slots.
File them smooth and put a bevel the ends. You will need a nozzle at the end
of the burner I use a 2 inch section of 1 inch pipe with a small section of
3/4 in pipe inside to take up a little space.  You will need to do a little
fitting here.  The tip of the jet need to be just at front end of the air
slots.  The burner should run from 1 to 35 psi.

Dan in Auburn WA 

-----Original Message-----
From: theforge-bounces at mailman.qth.net
[mailto:theforge-bounces at mailman.qth.net] On Behalf Of GRAF
Sent: Thursday, September 20, 2007 6:20 PM
To: Sponsored by ABANA
Subject: [TheForge] LP burner question.

I have and use a burner much like the one Frosty has up on:
http://www.blacksmith.org/drupal/forge_burner

It works fine in the forge. I now have another application which 
requires less heat than the minimum that I can get from this burner.

The fire pot that I use to heat my soldering coppers is regulated with 
only a needle valve, no pressure regulator. This makes obtaining a nice 
even heat difficult and when soldering for six or seven hours leads to 
too many trips to clean them do to overheating. In many ways the 
charcoal firepots that I grew up using were far nicer to work with.

At any rate, while working at the forge , it occurred to me that 
building a new LP fire pot with a pressure regulator would give me a 
much quieter, controllable and more efficient piece of equipment. The 
only problem is that the 3/4 inch burner is at least twice what I need 
for soldering, even when I crank the pressure down to near 3 lbs, where 
the flame  gets unstable.
I am only using 50/50 solder . If the coppers get much above 850 or so I 
can not move fast enough to keep from burning the solder which reaches a 
liquid state at half that.

So, has any one tried making one of these burners with 1/2 to 1/3 the 
capacity?
I'd appreciate orifice sizing suggestions still using the mig tips if 
possible. I wonder if 1/2 pip would be to large, perhaps 3/8?
I am guessing that the ratios in the sizing are not linear 1" > 3/4"> 
1/2 etc.



Mike Graf
_______________________________________________
Manage membership or unsubscribe at:
http://mailman.qth.net/mailman/listinfo/theforge
theforge mail list group photo site is
http://www.photoaccess.com
Login:  blacksmithblacksmith at hotmail.com
password:  anvil
___________