sdowney1 wrote:
I thought I would share this. 5 years ago I finished a mahogany transom
with minwax ipswitch pine and then topcoated with polycyclic. For some
reason it has held up well. Even though it is sold as an interior
product. Wood that got the polycrylic without the stain shed the
polycrylic in a couple of years and the wood turned grey.
Could the answer be the stain sealing the wood which allowed the
polycrylic to stay on the wood?

I don't know if this is relevant in this particular situation or not.
But when we stain a door, we stain it as opaque as possible to keep the
UV off the wood. ALL clear exterior finishes are problematic when used
alone, and much research by (not sure it was them) the Thermatru
corporation as well as others has proven that there is much less damage
to the wood when UV is blocked, not just mitigated. Uv damaged wood
dries out faster, shrinks, and moves which destroys the top coat. As
the top coat gets older and more brittle, it is less elastic and starts
to break down with movement.

Bearing this out, doors we have stained an opaque color and finished
last much better than the ones we just put a toner in the finish and
apply.

Robert