Painting over knotting solution

[PaulC78]

I recently got some new pine doors that I'm painting white. I've already applied a knotting solution to all of the doors and a single coat of water based primer to the first two. This has caused a problem though: what I think has happened is that the paint has raised the grain of the wood but not in the areas that were treated with solution, so the surface of the door now appears to have several sunken areas over the knots. I'm not sure if you can really tell from the photo, but the effect is quite noticable and I'm not convinced that further coats of paint will sufficiently cover it.

I've been recommended Zinsser BIN elsewhere, but since I've already treated the knots would I be better off with Zinsser Cover Stain?

Also, what am I best doing with the two door I've already primed? Sand them down and start over?

Any guidance is greatly appreciated!

 

[opps]

All waterbased paints cause the grain to swell.

I use waterbased primer, sand the raised grain back and then apply oil based undercoat (which does not raise the grain).

BIN is a good product but it dries too fast to enable a high quality of finish on areas such as doors.

I have never used Coverstain. I tend to stick with Leyland Trade acrylic primer because I expect to find imperfections that need sanding or filling. The Leyland is one of the few waterbased primers that is easy to sand. I sand it back so much that you can hardly see it...

 

[JohnD]

for good durability, Aluminium Wood Primer is great. Seals knots and resinous wood, oil based so does not raise the grain, no knotting required

but rather expensive for indoor work.