Re: Aluminium grade

At 04:41 PM 5/24/03 -0500, Jon Elson wrote:

>Fixtures are usually made of cast aluminum. Most aluminum plate and
>sheet are wrought (ie. rolled) aluminum, which has some more desirable

properties,

Besides being ground flat (as you mentioned) the cast tooling plate has
minimal internal stress, so it can be faced, pocketed, etc. without warping
(nice when you have large mechanisms you want to keep in line.) I have
been using the tooling plate for baseplates for several X-Y-Z mechanisms at
work. It has been actually running cheaper than 6061 of the same size,
bought new. I don't know the alloy either (I used to have an Alcoa
brochure on it but have since lost it) and the salesperson at Lusk didn't
either--it is just listed as "cast ground tooling plate".

Best regards,

Randy

Randy Gordon-Gilmore ,----.___________ ______________ _________________
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