Painting over knots in furniture

[Michael Weber]

Wife wants the dining room table and China cabinet painted black for a more formal look. Currently it’s reproduction stained “country pine” but good quality with a smooth not a rough rustic finish. The knots are very tight but would probably bleed through paint. I googled and the best advice I could find was to first use a putty knife to force wood filler into the knots to fill any gaps and then sand smooth. Then shellac over the knots followed by two coats of shellac based primer over the entire surface. Then paint. So it doesn’t look too DIYish I’d probably spray with my turbine HVLP. Sound reasonable for a permanent job with no future bleed through of the knots? What would be the best kind of paint to use? Don’t want latex and don’t mind having to order the paint to get the best looking and durable results. Appreciate your opinions about that projected process or your recommendations for improvement.Or if you think it’s an act of futility better not attempted. Thanks
pictures of the surface I’d be working with. 255C5400-EA8E-4FDD-8373-5E070EDD67A3.jpgBF10DE3D-5267-4491-A2B4-070A596D587F.jpg

[John TenEyck]

Yes, fill the knots and sand smooth. Then two coats of BIN shellac based white primer, tinted gray, then your choice of topcoat. I haven't used General Finishes black poly but I've used a lot of the white and it sprays great and is very durable, so I would think the black would be a good product, too. Target Coatings Black lacquer would be worth considering, too.

John

[Michael Weber]

Thanks John. Went to both web sites to investigate their coatings. Thanks for pointing out to tint the primer gray.

[Rich Engelhardt]

Exactly word for word what John said.
The B*I*N is necessary to seal in any and all sap that might be left in the knots - and those suckers can bleed sap for decades.

[Dave Zellers]

The B*I*N is necessary to seal in any and all sap that might be left in the knots - and those suckers can bleed sap for decades.

It requires a gentle touch but you can bleed most of the sap from the knots with a propane torch. Scrape it off with a putty knife. Go slowly. Then BIN. Works amazingly well.

[John TenEyck]

It requires a gentle touch but you can bleed most of the sap from the knots with a propane torch. Scrape it off with a putty knife. Go slowly. Then BIN. Works amazingly well.

That's good to know. Thanks. There's a post up in the Sawmill forum about sterilizing wood and Cody posted a link to an article by Christian Becksvoort about heating pine to 170F to crystallize the sap.

John

[Rich Engelhardt]

It requires a gentle touch but you can bleed most of the sap from the knots with a propane torch. Scrape it off with a putty knife. Go slowly. Then BIN. Works amazingly well.

I do recall hearing about that a long time ago. I was always too scared I'd set the wood on fire to try it myself.

[John TenEyck]

I do recall hearing about that a long time ago. I was always too scared I'd set the wood on fire to try it myself.

I suspect a hot air gun would do the job just as well with less tendency to send it up in flames, though I have charred a couple of things with it.

John

[Rich Engelhardt]

John - me too.( charred stuff w/a heat gun)

[Dave Zellers]

But it works! The sap comes bubbling out, scrape it off (maybe 2-3 times) then wipe with some thinner, let dry, sand, BIN, and paint. You would have to be extremely careful with a stain or natural finish job but with a paint job, slight charring is not a problem. I used knotty pine for some 1 1/8" thick pantry doors, bled all the knots and now 5 years later there is no sign of a single knot through white paint.

Not all knots have sap. If nothing happens, move on. Practice on a scrap first to get the timing. I thought of a heat gun too but haven't used the technique since I got one. Just go slow. Any sap you can bleed out will improve things. I've actually set the sap on fire!