I painted some knotty pine doors about 3 years ago but (despite applying knotting solution) knots are showing through on nearly all of them!
I followed the instructions on the bottle of the knotting solution (applying 2 / 3 coats with a rag IIRC) but obviously
- a) I did something wrong or
- b) the knotting solution I used (which was basically shellac) or
- c) these doors are really knotty
Any suggestions as to why I have such a paint failure are welcome but what I would really like to ask is... is there a product on the market that will
- paint over gloss paint
- and will definitely seal the knots
I do not like the idea of sanding the doors (I have nine) back to the wood and I do not want to have to repaint them every 2 - 3 years.
Follow up
I have done a bit of googling and found this post. It sounds like this Zinnser 123 or "ZinBin" are products similar to the "Kilz" paints mentioned by DA01.
I shall get one or the other (probably Zin123 since that is a bit cheaper and is soap+water cleanable (something I always like) unless anyone knows that ZinBin does a better job that is.