I have some red oak bookshelves that I’d like to finish. They are plain sawn, and have fairly big pores. Has anyone tried using the technique of sanding with a BLO/varnish/mineral spirits slurry to fill the grain? How has it worked? Any other techniques (e.g. with shellac) that work better? I’d just as soon not have to use a paste filler if I can avoid it,
Thanks-
Glaucon
If you don’t think too good, then don’t think too much…
Replies
While the oil/wood slurry may work somewhat with walnut or mahogany, the pores of red oak are so large that it's not going to be effective. Assuming you are not staining, you can apply a couple or three of coats of shellac, sand to the cut through point and do it again. I suspect it will take a lot of coats. (If you go this way use a fairly heavy cut of shellac. The pores of red oak are essentially like a bundle of straws running through the board, you don't want it so runny that you essentially fill the board with shellac.)
Frankly I don't see why a pore filler is that onerous, other than that it does have some waiting time in the process? Use oil based pore filler tinted to what ever shade you want. Then apply and then remove excess as soon as you see it start to haze. A plastic scraper, even a credit card on small surfaces, helps remove the major amounts and then a coarse cloth such as burlap removes the rest. With red oak you will probably have to make two applications of pore filler, spaced at least several days apart to get most of the shrinkage in the first application out of the way before "topping off" with the second. You don't have to cover an entire surface all at once--lap marks won't show.
Personally, I think red oak looks best with an in-the-wood finish made with the oil varnish mix. No filling required. Fully filled film finishes are rather formal, but red oak isn't usually the wood of choice for very formally styled pieces.
I generally agree with you on this, Steve, and usually prefer my oak just the way you do. Actually, a careful thin coat of shellac looks pretty good, too.
However, if OP hs a good reason to want a smooth film, shellac can take him there as can varnish. I am right now making kitchen counter tops out of salvaged white oak T&G flooring (living room buckled and had to be replaced, and I could not bear to send 400 sg ft to the dump). Because of the need for a tough, impermeable surface, I am using three coats of Behlens Rock Hard, each knocked back -- and the final will be rubbed out to a satin finish. However, under that are four coats of dewaxed blonde shellac (Seal Coat), each of which was sanded back and leveled. No grain filler was used. I noticed last night that there are a few small areas where I can still see traces of the oak grain under the first layer of topcoat, but expect even those to disappear under the next two sanded coats of varnish. The rubbing out will take away much of the heavy film look.
Joe
Yes, that's a system that works, though I'd imagine it will take more coats of shellac with red oak than with white oak.
Could be the red would in deed take more -- I wouldn't know. Are you assuming so because the red will absorb more into its unblocked pores?
" Frankly I don't see why a pore filler is that onerous, other than that it does have some waiting time in the process? 1. Use oil based pore filler tinted to what ever shade you want. Then apply and then remove excess as soon as you see it start to haze. A plastic scraper, even a credit card on small surfaces, helps remove the major amounts and then a coarse cloth such as burlap removes the rest. 2. With red oak you will probably have to make two applications of pore filler, 3. spaced at least several days apart to get most of the shrinkage in the first application out of the way before "topping off" with the second. You don't have to cover an entire surface all at once--lap marks won't show."It seems like you've answered your own question.Glaucon
If you don't think too good, then don't think too much...
Two applications versus 6-8 of shellac ? It does matter whether the time lapse is a factor. But there is nothing at all wrong with using shellac as the filler.
One plus that you don't get with the shellac is the ability to alter the effect of the grain a bit--making it lighter or darker. You could even dye the oak yellow and use purple pore filler.
As per my original post, I was asking about BLO/varnish/mineral spirits and sanding, not so much about padding shellac.Glaucon
If you don't think too good, then don't think too much...
I'll stick by my thought that I don't much like trying to fill red oak with the sanding dust slurry. Basically you are creating a pore filler with wood dust instead of silex. Silex has the advantage of not shrinking much, probably less than wood dust would do. The binder isn't that much different between the slurry and pore filler. You have exactly the same problem, if not greater, with shrinkage as the oil/varnish mix slowly cures and as the wood dries out. Consequently, you will still have to use multiple fillings, separated by several days if you want to actually fill the pores. You also have about the same problem in removing excess slurry from the surface as with pore filler, although the silex probably stays in the pores better when you wipe if off than wood dust which is much lighter. If you let the slurry cure on the surface you will not have much fun trying to sand off the excess since it will cure to be a soft, gummy mess, not much different from the problem you have with oil based pore filler if you wait too long to remove the excess.
Glaucon:
I didn't pad the shellac on the oak countertops I'm building. Brushed it with care, then levelled it later with 220 paper. Four coats; two on day one, and one a day for two days thereafter, for a three day overall process. Very smooth. Just put the second coat of varnish topcoat on. Grain is gone. The only distraction on the surface comes from my own mistakes, and from dust.
Joe
Just a note about applying the shellac. With reasonably fresh shellac, you can put the first three coats on in the total space of about an hour, and be ready to sand an hour after that. Subsequent coats need to be spaced a little further apart, but you can always put on at least three coats a day, especially if there is an overnight drying period somewhere.
You know, I have no trouble with doing the first two coats, MAYBE three, in an hour or so, but have had issues with drying times when I get much mil thickness. This is equally true of fresh-mixed flakes and Zinsser. I have found that with real film build-up, as in after the third coat of 3# as on a floor, it can take two or three days to harden enough to carry furniture.
Anyway, I have slowed down my shellac schedule after a few mishaps.
J
Lots of great ideas stored in the Finish section. You can narrow the search with fillers. I just finished reading a bunch of them. Might be helpful.
Dan
Dan,That's where I started... just curious if anyone had any first hand experience with them,Glaucon
If you don't think too good, then don't think too much...
Glaucon,
I tried filling the pores that way on a table top made with plum pudding mahogany veneer (If you've never seen it click on the link and scroll down to the second set of pictures, right below the crotch mahogany, really cool stuff!), and it turned out like crap. The mahogany dust had so much red in it that it turned out really blotchy. It also made the piece very dark and hid the figure instead of accentuating it.
I wasn't very happy as I had spent a lot of time making a diamond match with the veneer that turned out perfect, but the piece looked so bad that I trash-canned it. I know, I know, always do a test panel! I normally do, but I didn't realize that I needed to in this situation. This may not apply to red oak at all but anyone thinking of doing this with a similar wood to mahogany...you have been warned.
Rob
http://www.hobbithouseinc.com/personal/woodpics/mahogany,%20misc.htm
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