"40% cost and weight reduction" -- sounds good to me. They look like they would work fine for lighter duty machines. What would be the downsides of choosing wood over aluminum?

http://www.mkprofiles.com/profile_systems/mk_wood_Profiles.asp

This stuff looks to be much like the composite decking materials.

If that's true and all else being equal (cross section profile, size etc) this material will support ~ 1/20th the load than its equivalent in Aluminium. AL. modulus is 10 million psi. The composite wood/plastic materials are around 400-500 thousand psi.

I also suspect it might move a bit in use much as wood or the composite decking does..

Neat idea though..

This stuff looks really good! - http://www.mkprofiles.com/linear_motion/mk_precision_glides.asp

I found something more cost effective than the MK stuff. Click here: http://8020.net/Industrial/linearmotion.asp.

80/20surplus

I am not in any way trying to degrade anyone in my response. What I was trying to do is allow folks to see a cost effective alternative to the MK system that is made right here in the U.S. Thanks.

80/20 Surplus

Another manufacturer of profiling.

If you download the PDF it has some good ideas for connections and accessories.

http://www.boschrexroth.com/corporate/en/index.jsp