[TheForge] Re: TheForge Digest, Vol 34, Issue 69

[xlch58 at swbell.net]

Lynne Mork wrote:
>
>   Order of lighting and then turning off an oxygen/acetylene torch.
>
>   Over  40 years ago I was taught in the Utah Technical Collage (Welding
>   Class)  to turn the acetylene on first,. When shutting down,  turn the
>   acetylene  off  first.   The oxygen was supposed to clear the chamber.
>   When  I  retired  6 years ago, I went back to a welding school to make
>   sure  I  was current with new technology.  I was surprised to find out
>   they  now  teach you to turn on the acetylene first, and when shutting
>   down to turn the acetylene off last.
>
>   I  checked  in  my old books and found I was correct. The order taught
>   has changed!
>
>   Stump
>       
The basic debate seems to be that Oxy off first can result in the mixing 
chamber and torch internals being subjected to more soot that can foul 
it and lead to other problems.   Oxy off last can result in the flame 
being drawn into the mixing chamber and the torch internals being 
subjected to an acetylene flame. It is easier to blow out the soot on 
startup then assess damage caused by flame or overheating I am 
guessing.   I have been doing it acetylene first as I was taught for 
twenty years or so, and I know I won't change.  For some reason, I just 
love the scratch of the starter followed by the  pop of the acetylene as 
it ignites, and after doing it countless times it still puts a stupid 
grin on my face every time.

Charles