How can I prevent persistent knots bleeding through the paintwork?
This is on a new wooden window frame. This is outside, and has been exposed to all kinds of weather including lots of sunshine in the space of one year.
Pre-primed wood, knots were already just showing a brown mark through white primer. Water-based top coats used.
The paint just bubbled up quite a lot where the knots are.
Have twice tried to rectify this.
First time, scraped back blistered paint, removed paint where knot was. Cleaned with white spirit. Knotting solution, oil-based primer, oil-based undercoat, water-based top coat. Blistered up.
Second time, like above, except used Dulux aluminium wood primer instead of the knotting solution and regular primer. On top of the aluminium wood primer I used an oil-based undercoat and then water based top coat. Blistered up again.
I'm using water-based top coat because it matches the rest of the building.
The top coat is mostly dark green. There is some white top coat too, but the knot blistering isn't as bad on this, though still slightly occuring.
This is on a new wooden window frame. This is outside, and has been exposed to all kinds of weather including lots of sunshine in the space of one year.
Pre-primed wood, knots were already just showing a brown mark through white primer. Water-based top coats used.
The paint just bubbled up quite a lot where the knots are.
Have twice tried to rectify this.
First time, scraped back blistered paint, removed paint where knot was. Cleaned with white spirit. Knotting solution, oil-based primer, oil-based undercoat, water-based top coat. Blistered up.
Second time, like above, except used Dulux aluminium wood primer instead of the knotting solution and regular primer. On top of the aluminium wood primer I used an oil-based undercoat and then water based top coat. Blistered up again.
I'm using water-based top coat because it matches the rest of the building.
The top coat is mostly dark green. There is some white top coat too, but the knot blistering isn't as bad on this, though still slightly occuring.