Controlling vacuum table warpage

[jTr]

Anyone try keeping a sheet of ply / melamine or even plastic over the vacuum table for extended periods of idle machine time?

Just a thought that it may help a little bit in reducing moisture exchange and resultant table movement(?)

jeff

[coryatjohn]

Unless you can hermetically seal the table from the outside world, it would have virtually no effect. It's better to just expect it to breath and adjust accordingly. You could switch to a different substrate, like HDPE or PVC. A heck of a lot more expensive and probably, the results would be disappointing.