[ninewgt]

I agree - Good points Mike.

I wouldnt personally suggest a string level......except to rough check your frame if you wish. A 4' level is easier to use though - and much more accurate.

[m1911bldr]

All, many good tips concerning levels, parallel and such. I have just put together a 3x4 bed/table and had the opportunity to set it all up on a surface plate a friend of mine has. God, what a treat. The plate kept the Igus rails dead parallel to each other (in the vertical plane) and a faced-off piece of 1/2 drill rod was used to set the width. Then I placed the support rails/legs assembly on top of the Igus rails and bolted it all together with Brownell's gun bedding epoxy mixed with their metal powder acting as compressible shims. When I took it off the surface plate, the gantry (after I mounted it on the Y shuttles) slid from one end to the other with one TINY push. Hope you find a surface plate big enough to do your big table. Even one that is long enough to set the X rails on while letting them hang over a little on each end would work, I think.