Re: Identifying Alu and Steel parts

[Graham Singleton <grasingleton@avnet.co.uk>]

>.  Aside from the obvious weight difference between Alu and Steel, there 
>appears to be a distinct grain to the surface of steel parts, but not a 
>clear difference between regular and Stainless steel.

The only SS bits are the TP5 & 6. The TP4 torque tube is 4130, but plated, 
SS is not strong enough. It is worth trying not to scratch the plating , it 
will allow rusting to start.  Use a magnet as suggested, to identify 4130 
or ally.

Graham