Need some tips on machining my TM400 fork legs

[Lozza]

Seriously?  Does Chris take small jobs like turning fork legs and if so has anyone used him?  How are his rates?  I didn't see any contact information for him on the article in the link, does anyone have his contact info?  Thanks.

Just contact Chris through his website, if he can CNC a set of cases from scratch I doubt a pair of sliders will represent much of a challenge.

[GMC]

Casting grade 5083

You sure about that?
I would have said 6061 T6 as the fork is a structural part.

5083 is usually treated by cold drawing or strain hardening.
Basically the alloy is compressed, a bit like a forged piston, this is why 5083 is usually only available in plate form.

[Lozza]

Probably right there Geoff,got my series arse about, think the SAE is A356 which is what i got confused with
6000 series is not usualy cast more likely extruded.