[TheForge] Welding advice

[Ron Childers]

Ralph, would it be possible/ practical to rig an air jet on or in
conjunction with an electrode holder to cut with a carbon arc? A
made-for-the-purpose set-up is pretty expensive for a one time episode...I
have turned the heat up and cut (melted) steel with old wet electrodes-
seems like the carbon arc wouldn't care as long as it gets the air it needs.


Ron C 

-----Original Message-----
From: theforge-bounces at mailman.qth.net
[mailto:theforge-bounces at mailman.qth.net] On Behalf Of Ralph Sproul
Sent: Friday, February 25, 2005 11:59 PM
To: Sponsored by ABANA
Subject: Re: [TheForge] Welding advice needed pronto

Andy,  The air arc process could be compared to a weld eraser.

It is a carbon graphite rod which is used as a non-transferable heating rod
element that uses compressed air from under the rod holder in the torch head
to remove the molten metal the arc from that rod is creating.  It is a
noisey, nasty process that requires proper safety gear be worn so you don't
get badly burned.

It is also very effective in removing welds with less heat transfer to the
base metal than a cutting torch.  The spatter and debris shoot 5-30 feet
away - so being aware of fire hazards is a good thing to be on top of as
well when doing this process.

It takes DC reverse polarity (electrode positive) with at least 200 amps for
a smaller sized electrode, but the most common size is 1/4, 5/16 for use
with the 400 amp torches.  Common current settings are 350-500 amps for
carbon arc gouging.  So, you need a good sized welder with a good duty cycle
to do this process.

There are also flat rods compared to the common round rods.  I've used them
to "sculpt" a block of metal like a carving chisel before.

Ralph