The mating surfaces need to be clean and dry. 9 times out of 10, IME,
this will work:
clean both the male & female surfaces with a degreasing, "drying" type
cleaner, like automotive brake cleaner or (EPA & god forgive) MEK. You
are on the right track with the mallet. After the surfaces are clean &
dry, push the adapter up into the spindle. You can bring the spindle
down against the table to set it, but always give it a good whack or 2
with a heavy mallet, or, with a block of wood and a steel hammer,
about 2 lbs is right.
Larry Wasserman Baltimore, Maryland
Click to see the full signature.