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By PattyMac
#1194900
I have some pine furniture which I would like to paint. I have done this before successfully but I painted raw pine which had no finish on it. The pine I wish to paint now is the kind you buy in a shop with a "varnish" type finish - it's Ducal pine if that helps. Would I need to take the whole "finish" off or would a light sanding be sufficient for a primer to stick to?
Also, what's bothering me is ...... there are a lot of knots in it and as I've had it a while they are quite dark - I know if you use new pine on a door casing, for example, you have to use a knotting solution - would I need to apply this?? I've seen this type of furniture painted before but just wonder if everyone goes to all that trouble re taking the complete finish off etc.
I think you can apply chalk paint directly but that isn't the finish/paint I would like to use - I want to use Little Greene.
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By ED65
#1194948
You shouldn't need to go back to bare wood. A light scuffing up or sanding should key the surface sufficiently to provide a good bond, even with water-bourne paints going on top of varnish or lacquer. You can do an adhesion test on a small patch if you're worried.

Edit: has any of the furniture been in the kitchen? If so it's worth thoroughly degreasing the surface prior to keying the surface.

Knots, you're always safer if you seal them with shellac (knotting is shellac). Because the furniture is already finished in some way the knots may be sealed well enough, but shellac is a better sealer than most other clear finishes.

PattyMac wrote:I think you can apply chalk paint directly but that isn't the finish/paint I would like to use - I want to use Little Greene.
Most paints can actually go directly on to fresh wood, the requirement for primer, undercoat and then multiple layers of topcoat is largely applicable to exterior woodwork or high-wear surfaces on interior woodwork where long-term durability is desired.
By Just4Fun
#1194964
ED65 wrote:Knots, you're always safer if you seal them with shellac (knotting is shellac). Because the furniture is already finished in some way the knots may be sealed well enough, but shellac is a better sealer than most other clear finishes.

Why do you seal the knots? What might happen if you didn't seal them?

I remember applying "knotting" to new wood when I worked as a builder's labourer during school holidays in the 1970s but I don't remember what the liquid was nor why it was applied and I have never seen it since then.
By thick_mike
#1194982
For an adhesion test: apply the paint, allow to dry thoroughly, then apply sellotape to the new paint and pull off at 90 deg to the surface.

A better test is to crosshatch through the coating with a Stanley knife prior to the tape pull off test, but that would make a mess of the chair.

You could try several different pretreatments, eg none, degrease, degrease and light scuff, and sand to see which gives the best results.
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By ED65
#1195000
Just4Fun wrote:Why do you seal the knots? What might happen if you didn't seal them?
They can weep out resin over time if not sealed sufficiently.

You might have noticed some brown spots on light-coloured doorframes or skirting board? They look a little like localised tobacco-smoke staining. That's the resin coming right through the paint. The resin is an incredibly good penetrator, it can slowly work its way through primer, undercoat and paint!

Just4Fun wrote:I remember applying "knotting" to new wood when I worked as a builder's labourer during school holidays in the 1970s but I don't remember what the liquid was nor why it was applied and I have never seen it since then.
It is still made and is widely available, usually found near the varnishes. But any form of shellac will work if need be.

A stain-blocking primer should do the job too, but some still swear by those that are based on shellac like the original version of Zinsser's BIN.


thick_mike wrote:A better test is to crosshatch through the coating with a Stanley knife prior to the tape pull off test...
This.

The above is the acid test for adhesion. You can do it on any of the finished surfaces so it can be done on an inconspicuous spot that isn't seen normally, like the inside face of a leg near the top.

Undersides of tabletops are good places for spot-testing too, but they're not always finished to the same level as the rest of furniture.
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By custard
#1195103
PattyMac wrote:I want to use Little Greene.


The big advantage Little Greene has over Farrow & Ball is that L.G. offer abundant technical advice that covers use of associated products from other manufacturers. With F & B, if they don't make it then it's never even mentioned.

Bottom line, contact L.G. direct. They know far more about their products than anyone else, furthermore they have a vested interest in you achieving a satisfactory outcome.

Good luck!
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By thetyreman
#1195105
definitely seal the knots with shellac first, de-waxed shellac, I make my own with alcohol and shellac flakes, liberon sanding sealer would do the same thing, once sealed you can then sand it, I recommend always sanding pine before painting it to 150 grit. Also prime it and fill in any holes or marks you find before the final coat, it'll turn out much better and is well worth the effort, dark colour will require a grey primer, light colour white primer.
By Mark A
#1195162
I recently bought a large pine cabinet from eBay for £40. Keyed the surface with 180 grit, gave it two coats of Zinsser BIN followed by two coats of F&B.
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By Nelsun
#1195164
Zinsser BIN covers all magnitude of sins and lightly sands to a very smooth base for whatever you want to do. It's is a joy to use and you can put anything over it (some knotting stuff wants oil based over it). It's not the cheapest though but worth buying in bulk if you've any glimmer of other painting anything jobs on the horizon.
By PattyMac
#1196305
Thanks everyone for the advice and sorry for the late thank you - just caught up in Christmas.
I did use Zinseer primer when I painted the raw pine.
Can anyone answer other question re knots and bleeding - I have a door frame which I recently painted from raw pine - I used Colron knotting solution and applied it liberally but the knots have started to appear - How do I go about getting rid of these now - can I? Or would I have to take down to the wood again?
By MikeG.
#1196319
PattyMac wrote:.......I have a door frame which I recently painted from raw pine - I used Colron knotting solution and applied it liberally but the knots have started to appear - How do I go about getting rid of these now - can I? Or would I have to take down to the wood again?


Many professional decorators apply knotting after primer, or a mist coat. Therefore I can see no reason to take your bleeding knots back to bare wood.

If painting such timber in future, consider routing out a shallow circle (say 5 or 6 mm deep) to totally remove the knot from the surface. Then fill with a 2 part filler, and sand back when dry prior to painting in the normal way.
By Jacob
#1196332
Wash down with sugar soap solution, rinse and dry. Almost anything will stick to that. You might as well dab in the knots with "knotting" as it's quick and cheap - basically a thick shellac solution, but I wouldn't worry if a few bleed later - it's a feature of the wood you can't make silk purses from sows ears!
By PattyMac
#1196755
Thanks for the replies.
Setch - I have some Zinseer so I'll try that.
Jacob - yes I know what you mean re silk purse out of sow's ear - these door casings are new and quite honestly they've been murder to paint and prep. I've rubbed down, applied knotting soln., primed twice with a rubbing in between and applied three coats of satin - again with a rub down and they still look - to me - new and awful. I painted the new staircase in L&G and the finish is beautiful and almost effortless. However, when I painted the first casing in this it looked as though it was just undercoated so I went with a satin. I used a good quality brush and paint but it seems as though the finish is not even and patchy.
Old paintwork can be rubbed down and you get a good finish for your effort - heaven knows how long I'll have to wait for this paintwork to "age".