# Finishing Oak Plywood



## kthode85 (Jul 20, 2010)

Hey guys

I am wanting to put a durable finish on some oak plywood. This will be used as a computer desk. I am looking for a good finish for this and I read that polyurethane may be the best for this application. All I really am doing is rounding the edges off and then staining/finishing the plywood so its nothing too fancy. 

I first want to stain the piece and then put the finish coat on. 

Do I need to sand the wood before/after I stain it? If so what sand grit should I use? The same goes for the finish, if polyurethane needs to be used.

Thanks for the help!


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## cabinetman (Jul 5, 2007)

kthode85 said:


> Hey guys
> 
> I am wanting to put a durable finish on some oak plywood. This will be used as a computer desk. I am looking for a good finish for this and I read that polyurethane may be the best for this application. All I really am doing is rounding the edges off and then staining/finishing the plywood so its nothing too fancy.
> 
> ...


A raw plywood edge won't provide a very finished look. You might want to consider edging it with solid wood.

You might want to very lightly sand the bare plywood with 150x-180x with a ROS, or a block sander sanding with the grain direction. Be very careful, as the face veneer is very thin. This sanding is just to clean up the face and remove handling marks. 

Use the stain of your choice, but don't sand. Apply your topcoat. You can use a wipe on version of an oil base polyurethane, or I would recommend spraying if using waterbase polyurethane. Sand in between coats with 320x.












 







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## TGRANT (Jan 25, 2011)

As you could guess from my previous posts, I’m a big fan of spar varnish. The accompanying picture is a desk I built eight years ago. I use it as a computer desk, an electronics test bench, and a taboret for oil painting. I spill coffee, turpentine, oil paints (and other substances you might not want to hear about) on it regularly. I also drop stuff on it all the time. I clean it with Windex. The desk is oak veneer plywood with a solid wood edging. You can see the reflections giving some indication of the gloss - after 8 years.

I thin spar varnish with turpentine in a 4:1 ratio of varnish to turpentine and add a few drops of Japan dryer. Using a brush, I put on 4-5 coats, one coat a day, gently sanding with 320 grit sandpaper between coats. I finish up by rubbing out the final coat with 4-f pumice stone. The finish is glass smooth and the pores fill with the varnish almost, but not all they way. You could get rid of all the pores with a filler before you start to varnish. It’s a bit fussy, but I’ve used the finish on kitchen tables and bathroom cabinets built out of red oak and red oak plywood, and they are relatively indestructible. You might need a few days between coats in cooler weather - depends on your shop. Dust is a bit of an issue, but I’ve not had major trouble with it. Just clean your shop the night before and let the dust settle.

My gripe with poly is that it ends up getting scratched and begins to look like scratched plexiglass after a while, and the finish begins to look dull. Spar varnish does not seem to do this. I will admit I haven’t used poly for many years (after my experiences described above) so newer products might be better - I don’t know.


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## kthode85 (Jul 20, 2010)

TGRANT said:


> I thin spar varnish with turpentine in a 4:1 ratio of varnish to turpentine and add a few drops of Japan dryer. Using a brush, I put on 4-5 coats, one coat a day, gently sanding with 320 grit sandpaper between coats. I finish up by rubbing out the final coat with 4-f pumice stone. The finish is glass smooth and the pores fill with the varnish almost, but not all they way. You could get rid of all the pores with a filler before you start to varnish. It’s a bit fussy, but I’ve used the finish on kitchen tables and bathroom cabinets built out of red oak and red oak plywood, and they are relatively indestructible. You might need a few days between coats in cooler weather - depends on your shop. Dust is a bit of an issue, but I’ve not had major trouble with it. Just clean your shop the night before and let the dust settle.


Thanks for the recipe, i just bought satin spar varnish, turpentine and japan drier. i laid down the first coat; it looks like its going to work out! ill post pics when its done


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## kthode85 (Jul 20, 2010)

TGRANT said:


> gently sanding with 320 grit sandpaper between coats.


Do you sand with a block or by hand? it looks like ill have to sand the whole piece down, stain it again and then varnish it; i used a block and i think i burned through the varnish and through some of the stain, yet there were still valleys in the wood with unsanded varnish. im wondering if i should just put straight varnish with japan drier instead of diluting it down with turpentine.

Does everything have to be dull before I put more varnish on it for a 2nd coat? Also for the first coat, do I need to leave the coat on thick or should it be spread out as much as possible?


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## TGRANT (Jan 25, 2011)

I use a cork block and just sand enough to knock off any of the rough spots. Don’t sand too much. I don’t aim for everything to be dull. You risk sanding too deeply. Diluting the varnish makes it flow into the pores more easily, and eliminates brush strokes, but you can apply the varnish straight. I’ve tried it both ways and I get the best results with a slight dilution. 

As you’ve learned, there is a risk of sanding through the first coat into the varnish if you sand too much. There is certainly many ways to do this, but my smoothest results come from thin coats, with very light sanding between coats.


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## GeorgeC (Jul 30, 2008)

My computer desk is finished in lacquer. Has stood the effects of the world well for 10ys.

G


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