Barry,
While not for furniture, I use SEAL COAT frequently. For me, the typical use
it to coat & seal my hardboard templates. Both the 1/8in 'drawing' and the
1/4in 'router'. Extra 'protection' coats go on the edges.

Contrary to the 'experts' my favorite brushes are the 'disposable CHIP'
brushes for Epoxy, and the foam ones for Varnish. {YES - goes against what
all the 'pundits' say . . . but it's really technique & care that counts !}.
When I first started to use the SEAL COAT, a foam brush was what I used. As
I proceeded I noticed little BLACK bits in the finish . . . Turned out that
the ALCOHOL was DISINTEGRATING the foam brush !!! I then switched to the
'chip' brushes and no problems.

So the question is . . . what 'type' of FOAM brush are you using ???

Regards & Thanks,
Ron Magen
Backyard Boatshop

"B A R R Y" wrote
SNIP
My absolute favorite, truly universal, sanding sealer is Zinsser Seal
Coat, which happens to be a simple premixed 2 lb. cut of dewaxed
shellac. . . .
SNIP

.. . . applied with a foam brush . . . .