Jerry and list
The one thing that started all of this was the early rear engine and a few
front engine dragsters were showing up at the lakes. Most were .049 wall
tubes and due to the many cycles of drag racing, transportation and running
on the dry lake bed with some rough areas we started seeing failures. Lots
of cracks and in one case the dragster turned lakester got up side down and
tore the roll cage off the car. The cage was to the specs but the attaching
tubes were O-to-thin and tore the material right out still welded to the
roll cage. It was a fatal accident.
We had several chassis builders look at the wreakage and they first
recomended some changes to better re-inforce the cages etc. They also stated
that mild steel is the better choice for long wheel base cars due to lots of
flexing. The rule book states any frame can be used, but must be approved by
the contest board. The burden of proof is up to the owner/builder.
Glen
----- Original Message -----
From: "Richard Fox" <v4gr@rcn.com>
To: "Jerry Dickinson" <og_1leg@hotmail.com>; <land-speed@autox.team.net>
Sent: Wednesday, February 21, 2001 2:42 PM
Subject: Re: Why not use 4130
> Jerry; Also 4130 is a heat treatable alloy. Since the welded area will
cool
> fairly rapidly it may well be one stage heat treated and brittle. Aircraft
> 4130 weldments are annealed or heat treated and drawn before use. 1018
will
> not heat treat without adding carbon, so will not require annealing. Rich
> Fox
> -----Original Message-----
> From: Jerry Dickinson <og_1leg@hotmail.com>
> To: land-speed@autox.team.net <land-speed@autox.team.net>
> Date: Wednesday, February 21, 2001 11:48 AM
> Subject: Why not use 4130
>
>
> >Why does the rulebook recommend Mild steel and not 4130? I know 4130 is
> more
> >diffacult to weld, but I would think if you had a welder that could weld
it
> >right 4130 would be stronger.
> >_________________________________________________________________
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