The collar that holds up the table and slides up and down the mast
support column to raise/lower the table is in need of servicing. It is
rusting on the inside and not allowing proper movement. I know that
there are nylon sleeves/collars inside the steel collar tube. There
seems to be no way to remove the collar. Even the mast column has a
wleded flange on either end, so removing the mast support column will
not allow removal of the column. Does anyone have any experience with
this?