flat, light surfaces

On the subject of making a flat, light weight working surface, you might
think about the optical tables that are commonly made by Newport Corp and
TMC. These have 1/8" thick SS skins separated by aluminum honeycomb, which
is adhesively bonded to the outer skins. They work pretty well, and are
much lighter for a given size and stiffness than other affordable tables
(granite). As important as the stiffness is the grid of 1/4-20 holes on 1"
grid over the entire surface. These tables are available quite long- at
least 4x12 feet, probably much larger. Also are pretty expensive.

I think they get flattened, ground SS (magnetic) and lay it on a big granite
flat. they gob some glue on, put on the honeycomb, more glue, and a second
sheet of SS, then an airbag to apply pressure.

The basic idea works well when made of plywood. Sheets of styrofoam can be
used instead of honeycomb, this is sort of a surfboard.


Look at www.newport.com and search for vibration control or table.


To keep on topic, these tables usually have passive vibration control, they
have legs that contain mechanisms that act like long pendulums and air
cylinder levelers. This does a pretty good job of isolating the table from
ambient vibration. For a higher level of isolation they use servos and
accelerometers.

Would a machine tool produce a better finish if vibration was cancelled out
with some active servo?
This might be a way to make a lighter machine. Imagine dynamic balance
being done constantly.

Elliot Burke