knotty problem

[Ratty2E]

We replaced the skirting in our lounge a couple of years ago. We used pine skirting board and used knot sealer before painting but the knots are still showing through. I have painted them with stain sealer paint too but they always come back. It's driving me mad because it looks awful. If I sanded them down and put varnish on before painting would that help?

[kinell]

if you must use wood with knots in it.....

if you were going to paint it anyway whats wrong with mdf?

if you want natural pine bite the financial bullet and buy parana pine

[The Builder]

A good stain blocker such as Zinsser should do it, Ratty.
Otherwise, before they were available, in the "old days" they used aluminium paint. Works well.

[heathfield]

Annoying, isn't it? The resin in knots eventually bleeds through normal paints to create a stain. There's a stuff called ''knotting'' which has been used from Victorian times to prevent this. It's a shellac varnish which seals off the knots and stops the resin bleed-through. Dries in less than an hour. Two coats recommended. Available in brown and milky white, from DIY stores and most good hardware shops. Otherwise, Dulux do an aluminium-based primer that works well, (as Builder mentioned),on knots, and even on older bitumen and creosoted surfaces.

[Ratty2E]

Thanks Kinell, but it's bit late now as I said it was done at least 2 years ago and hind sight is a wonderful thing.
Heathfield, I did put knotting solution on before we painted and just checked and Builder, the stain blocker I have painted it with since was Zinsser. *sigh* looks like I have particularly persistant knots. Thanks anyway.

[AlBags]

You can also help by burning out a lot of the resin with a torch/heatgun first .. then flatting .. then sealing.