"marc rosen" wrote in message
ups.com...
Hello Group,
I did a google search on this subject and most of the reasons were to
lock in the vapors. I want to use a very heavy (1&1/2 inch thich)
former computer lab desk for my router table. I have routed the cutout
for the insert but I'm reluctant to set the insert in without treating
the raw material. Do you think there is any chance the MDF could swell
when polyurethane is applied? (Also, if that were a problem, I suppose
I should avoid aqueous polyurethane.)


A coat of two of poly won't swell it, but they will reduce the tolerances.
Are you sealing it for vapor? If so, that seems kind of anal to me.