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Post by mrbmcg on Dec 12, 2007 23:19:07 GMT
Hi All I normally spray finish my stuff with pre-cat laquer, however due to circumstances beyond my control I have no spray setup at the minute. I decided to finish a little Walnut table with Liberon finishing oil. The recipient of this piece of furniture said they would like a "glossy, but natural" looking finish.  Well, 12 coats of oil later, it certainly is glossy, but not particularly natural looking. My natural instinct is to reach for the Black Bison Wax and wire wool to take the edge off the "plastic" shine. However, is this the thing to do with oil finishes and if so, how long should I let it cure? The last coat went on two days ago. Any advice for a first time oil user?  Cheers Bob |
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Post by thallow on Dec 13, 2007 6:59:22 GMT
wwwhhhoooaa I was expecting to see a scantily clad shiny woman! ;D Sorry Bob, you probably know more than me already  oh & welcome by the way! |
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Post by mrgrimsdale on Dec 13, 2007 9:31:37 GMT
Sounds like too much oil. As I understand it you wouldn't have 12 "coats" of oil but you might have 12 applications - each one applied when the previous one is dry, and more or less rubbed right off, leaving very little actual oil on the surface but hopefully well filling the wood.
As they say - once a day for week, once a week for a month, once a year etc etc, but never any accumulation on the surface.
cheers
Jacob
PS if you've got a thick varnish-like layer you could take it off with Nitromors. It's quite gentle if you do it carefully and can leave an oil filled surface untouched. Soak it up and take it off with sawdust/shavings and clean up with oil and turps mix praps.
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Post by evergreen on Dec 13, 2007 12:34:41 GMT
Bob
Your client has given you a contradictory brief - in my book, "glossy" cannot be "natural"!
I guess they mean leave the grain pores showing?
I've never used Liberon finishing oil but 12 coats of any non-tradional oil seem way too much to me. These modern finishes are usually formulated to produce a result quickly and are often oil/varnish combinations. I'd knock the surface back but using a Webrax pad or just a plain old non-scratch scouring pad. I think wire wool has too many disadvantages. Then I'd give it just one coat of Danish oil, you've already done all the hard work of saturating the top surface of the wood. If it's still too shiny, knock it back again and try one coat of boiled linseed oil.
Incidentally, I never use wax on top of oil. OK, I'm the only person in the world with this strange perversion but I just think that a light oil finish is enough. It's subtle and lets the wood show its stuff. But if your client wants "glossy", you've got to give it to 'em...
Regards.
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Post by mrbmcg on Dec 13, 2007 18:48:36 GMT
Thanks for the replies guys. I think Jacob has hit the nail on the head. As background, Its a Walnut table and was in a bad state of repair when I got it. It was originally covered in shellac, but the girl wanted a finish that was a bit tougher than that as it had a lot of marks on it and a plantpot water stain too. its not an antique or anything, so my plan was to give it a few coats of sanding sealer to fill the pores then a coat or two of gloss pre cat and knock it back with some wire wool and wax to still have a glossy look, but not plasticy the way pre cat can look from the gun. Anyway, due to being without a spray set up and having a tin of Liberon Finishing oil lying about (and promising I would get it to her by Christmas about 2 months ago  ) I thought I would get started with something. As I said, Jacob has hit the nail on the head. I wasn't wiping the oil completely away, I was trying to build up a film on the surface. Every 3 coats I left it for a day or so then cut it back with 400 grit. This eventually sealed the pores pretty well. The problem is though, that as I am a bit new to oil finishes, I'm not sure if all these layers will cure. And also, is the top layer hard enough to cut back with wire wool like pre cat is after a few hours? I don't want to end up with a matt finish after all this hassle. (Starting again is not an option BTW as I've no time) So, all that said. Will all these layers cure hard enough for me to buff it with wax and wire wool and get a non-plasticy, glossy(ish) finish do you think? I guess i just go for it on an "Inconspicuous" bit eh? ;D |
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Post by Keith on Dec 14, 2007 18:19:02 GMT
I'd get some 250 or 400 grit wet and dry and soak it in 50-50 mix of oil and turps. Then rub over the surface with it until I had got through of all the excess oil. The slurry needs to be completely removed to the point you have a more or less dry surface. The table should then be left in the warm for 24 hours for the finish to fully harden. After that a couple of light coats rubbing off any excess should give you the finish you want.
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Post by mrbmcg on Dec 14, 2007 22:54:49 GMT
I'd get some 250 or 400 grit wet and dry and soak it in 50-50 mix of oil and turps. Then rub over the surface with it until I had got through of all the excess oil. The slurry needs to be completely removed to the point you have a more or less dry surface. The table should then be left in the warm for 24 hours for the finish to fully harden. After that a couple of light coats rubbing off any excess should give you the finish you want. Thanks Keith. I Bottled out of doing anything with it tonight, but I might give that a go in the morning. Can you use shellac over oil? Just wondering. |
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Post by Keith on Dec 15, 2007 9:36:24 GMT
No..
You should get a good finish with the oil, although one thought, is it old? The solids can sink to the bottom of the can and solidify, give it a good shake/stir, and if it is more than a couple of years old it would be worth getting a new tin.
If you are still not happy with the finish you could try mixing finishing oil with solvent based polyurethane varnish 50-50, this can be thinned with turps if it is a bit thick, and apply this just like an oil; ie very thin coat applied with a cloth and no excess left on the surface.
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Post by mrbmcg on Dec 20, 2007 21:24:25 GMT
Thanks to everyone who gave advice. The problematic table is back with its (satisfied) owner.
;D
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Post by Sgian Dubh on Dec 21, 2007 9:02:14 GMT
That's not quite correct Keith. Maybe I've misinterpreted the purpose of your post in that you were trying to offer the best advice to complete the specific job at hand, but shellac can be applied over just about anything. If I have misunderstood I apologise. Shellac is probably one of the most versatile finishes and will adhere very well to a range of 'difficult' substrates. It's frequently used as an intermediate coat between a difficult ground and the preferred finish that goes over the top. For instance, if the base is an oily wood such as teak, or there is a suspicion of contaminants such as silicone, shellac will adhere and provide the link to other film forming polishes that would not themselves key with the contaminated substrate. After the shellac has created this sound base then nearly every other type of film forming polish will adhere to this. The only proviso is that water based film forming polishes are sensitive to waxes and oils under them and don't adhere as well as they should if this is the case, and can fail. So the safest bet is to always use a dewaxed shellac as the barrier because every film finish adheres to this. Normal shellac, which is naturally waxy, is compatible with all other film forming polishes that might be applied over it, eg, oil based varnishes, nitro-cellulose based finishes, etc. Slainte. |
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Post by mrgrimsdale on Dec 21, 2007 11:04:29 GMT
That's interesting I didn't know shellac was quite so sticky.
What I have noticed on old and neglected joinery is that often the only bits of paintwork still in good order are on top of shellac knotting. Also you often find glazing rebates primed with shellac also often in amazingly good order even after 100 years or more. Sometimes the whole glazing bar/stile/rail has been primed the same, and the lead paint burns off really cleanly leaving new-looking surfaces.
Surprising cos shellac alone itself is not weather resistant.
cheers
Jacob
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Post by Sgian Dubh on Dec 21, 2007 12:45:24 GMT
That's interesting I didn't know shellac was quite so sticky. Jacob Surprising cos shellac alone itself is not weather resistant. Jacob Shellac is possibly the greatest all round or universal primer Joseph. There are circumstances where it's not the ideal top coat, but it's hellish good as a sealer and base coat for other finishes, as your observations of old surviving shellac primed joinery anecdotally supports. It's great stuff for providing a seal on internal furniture parts, eg, drawers. Got a stinky cabinet interior from smoke, moth balls, or some nurk's applied a pure oil finish like linseed oil or pure tung oil on the inside? Brush, wipe or spray shellac on to seal in the stink. Going back to architectural joinery, your specialism I believe, much of which is of resinous softwoods, eg, pine, then shellac in the form of knotting is often able to hold the oozing resin in the wood thus preventing it breaking through the paint film. This extends the life of the structure as it holds the film of paint together preventing water ingress and mould development. Nowadays, properly kiln dried resinous gymnospermae should have resin that doesn't ooze because it's been set solid with short periods of extra high kiln temperatures designed to do that job. But it's not always done successfully for a variety of reasons, not all of which are the kiln operator's fault. I don't often use shellac as a finish in its own right, but I use it a lot as a barrier coat. Between dying or staining and grain filling for instance, or between other processes where you don't want the layer below affected by the next colouring or toning stage, etc. Naturally shellac cannot be used beneath pure oil finishes as it prevents their absorption into the wood, but it can be used beneath things like Danish or teak oil. These are really little more than expensively packaged and cleverly marketed thin varnish formulations despite the manufacturer's baloney about hardening, feeding and nourishing the wood. If anyone wants a Danish oil finish, just buy some varnish and some white spirits and you have all the necessary ingredients to mix your own. About 75% white spirits to about 25% varnish does for the first two or three coats-- maybe stick in a spoonful or two of boiled linseed oil just to soften it all up a bit and just wipe it on. Then 50/50 varnish and white spirits for a top coat and you've got something that closely matches a Danish oil formulation with added durability due to the omitted linseed oil in the final coats. Slainte. |
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Post by Keith on Dec 21, 2007 12:52:10 GMT
My thoughts were that he had applied too much oil and needed to remove most of it to get back to a position where he could build up the required finish. I didn't think that applying shellac at that stage would have been a practical option for him, particularly as it was likely that some of the oil had not cured. Once he had removed the excess oil it would have been quick and easy to obtain the finish he required with a couple of thin coats of finishing oil.
However I must admit that I too didn't know that shellac was so versatile and would adhere so well.
Best regards
Keith
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Post by dom on Dec 21, 2007 18:34:01 GMT
As a self confessed numpty when it comes to finishing. Thank you, very helpful.
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Post by paulchapman on Dec 21, 2007 20:43:15 GMT
Yes, very helpful. I think most people find finishing a bit of a black art  That shellac sounds like good stuff. Cheers  Paul |
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Post by mrgrimsdale on Dec 21, 2007 23:49:15 GMT
Shellac as french polish or knotting scores highly for bouquet and alcohol content but tastes appalling and you can't get it off your teeth for years. Nicer than bailieys irish gunge though - mrs G has just polished off another bottle!
cheers
Jacob
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Post by engineerone on Dec 21, 2007 23:52:17 GMT
so let me get this straight, mrs grim is your polisher  paul |
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) I thought I would get started with something.
