[Land-speed] Fw: Welding info

[Chris Harris]

List,
Below is a request from my brother in law who is an engineer at a local fast 
expanding aircraft business involved with virtually all aspects of small to 
medium size aircraft from contract flying through maintenance and 
fabrication. Any advice or recommendation would be greatly appreciated.
Chris Harris.......................NZed.


Subject: Welding info

> Hi Chris, For some time now we (Farmers Air) have been doing our own
> repairs to our Landing gear and other Steel (mostly chromemoly 4130)
> structural components. We have recently gained certification to
> produce and use our own designed components. The problem that I have
> relates to locally welded components and the quality of the welding,
> by this I mean mostly the appearance of the weld (T.I.G) Even though
> the welders that we use are certified and the welds pass the ministry
> tests....the appearance leaves a bit to be desired, especially when
> compared to the welding you see produced by the various Hot Rod/Race
> Car Chassis builders in the US. The problem we have is getting
> information about what Filler Wire these guys in the States are using
> and (if any) special blend of Argon. The best Filler wire we have
> been able to get here is a generic type PZ6500 with 3 1/2% nickel
> mix. While this produces a reasonable looking Cap...it still falls
> somewhat short of what those American Race Car Chassis builders are
> producing. Is there any way you could find out for me just what it is
> that they use when welding 4130 Chromemoly tube. Cheers Warrick
>
> Warrick and Donna Smith