Re: 4130 welding

["Art Gale" <gale@candw.ky>]

Maybe less than "scientific"... weld a bit and grab a hammer and beat the
stress out of it!!  (I realise this is a "rough" method...but it sure
reduces warpage!)

Worst mistake are long continuous welds hosed down right after cooling!


----- Original Message -----
From: <BillDube@killacycle.com>
To: <ev@listproc.sjsu.edu>
Sent: Tuesday, February 27, 2001 11:47 PM
Subject: 4130 welding


> Paul C wrote:
>
>  > There are applications where 3140 is appropriate,
>  > mostly where a
>  > significant degree of flexure is expected, i.e. aircraft and
>  > bicycle frames.
>
> It's worth noting here that most of the frame gurus insist on TIG welding
> 4130, even though it was *designed* for gas welding.  TIG gives you pretty
> welds.  It also causes drastic thermal transients in the metal, which is
why
> you have to treat it after a TIG weld.  The PROPER way to do it is to use
a
> big, soft gas flame and take our time.  That ensures heat spreads
gradually
> throughout the area.  Yeah, the welds look cobby.  They're also probably
> stronger.
>
>
>  >>>>>>>>>>>>>>>>>
>
> The American Welding Society specifies TIG as the best method for welding
> 4130 tubing. If you wish to get technical it is not "TIG" but, according
to
> the AWS, it is "GTAW." This stands of Gas Tungsten Arc Welding. They call
> it this because the shield gas is often not truly "inert." GTAW results in
> the best weld strength for 4130 tubing.
>
> If you are going for the absolute top strength, you must heat treat the
> entire completed structure in a tempering oven. This relieves all the
> thermally-induced stress in the heat-effected zones, but also converts all
> the martensite back to austenite to restore the full toughness of 4130.
>
>
>     _ /|        Bill "Wisenheimer" Dube'
>    \'o.O'     <billdube@KillaCycle.com>
> =(___)=
>         U
> Check out the bike -> http://www.KillaCycle.com
>     _ /|        Bill "Wisenheimer" Dube'
>    \'o.O'     <billdube@KillaCycle.com>
> =(___)=
>         U
> Check out the bike -> http://www.KillaCycle.com
>