# Sanding Plywood with a Drum Sander?



## Phred (Mar 18, 2008)

Hey There,

I just finished sanding and staining, and lacquering a whole bunch of Maple cabinets, and.. boy.. I'm tired of sanding…..

My question to those out there, can you, and do you use a drum sander to sand Cabinet grade plywood? I had to take the plywood down to 100 Grit, then 150 or it would blotch real bad. It took a HELL of a long time, and I'd rather like to avoid it for the next time, and I'm thinking about running the plywood through the drum sander, then a final sand with the RO sander to reduce some labour.

If not cabinet grade plywood, then would you sand Baltic Birch? (thicker top ply) I have a lot of drawers to sand now, and I just don't want to. I'm thinking it's time to buy a drum sander, but if it's not a good idea to sand plywood, then I might just pickup a better RO sander.

Thanks

Nick


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## CharlieM1958 (Nov 7, 2006)

You can sand plywood any way you want as long as you don't sand through the top layer of veneer. 

Smart a** answer, I know, but what I'm saying is all depends on the veneer thickness of the plywood. I've sanded some cheap plywood with a hand-held sanding block and gone through the first ply.


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## TheDane (May 15, 2008)

Actually, sanding plywood was one of things I had in mind when I built my drum sander … http://lumberjocks.com/projects/29085.

Haven't used it for that purpose yet, but it takes such a light cut I think it might be the best way to avoid sanding through the top ply.


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## PaulfromVictor (Mar 29, 2009)

It would be easy to accidentally sand through the veneer, but you could carefully do it. I am not sure how much time you would save though, because, as you said, you will still need to ROS to eliminate the sanding pattern that the drum would leave.

If you want a drum sander, you can build one to your needs much cheaper than you can buy new. See my favorites for some drum sanders made by others. There is not much too them mechanically. I am currently building one with about a 20" capacity for a cost of a little over $400. If you have the time and inclination, it is a fun project.


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## SnowyRiver (Nov 14, 2008)

I agree with Charlie, you can sand anyway you want, but have to be careful not to sand too deep. For that reason I always sand plywood by hand. I find that using the 3M sanding pads works best and easiest.


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## Phred (Mar 18, 2008)

I had a lot of trouble with this plywood, it seems the blotching was maybe from the glue/adhesive used under the veneer. (standard veneer core plywood, domestic) using a pre-stain solved the problem, but changed the colour too much. sanding thoroughly (drawing lines with a pencil then sanding off) seemed to solve the problem, but it sure was a lot of work!!

Just looking to save some time on the next one..


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## richgreer (Dec 25, 2009)

It is too darn easy to sand through the veneer. I'm very cautious when I sand plywood and I take a real minimalist approach.


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## 747DRVR (Mar 18, 2009)

If maple wants to blotch I dont see how sanding with a coarser grit and then going back up is going to help you.If you dont like the color penetration when you use conditioner maybe you should try a gel stain


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## docholladay (Jan 9, 2010)

I agree that it should not take that much sanding if using cabinet grade plywood. With the blotching, I think I would have to try using a wood conditioner and then using a gel stain or glaze to get the color or tone that you want. It takes a little bit of experimentation, but not near the labor of all that sanding. I am amazed that you didn't sand through the veneer with all of that sanding.


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## Ingjr (Feb 21, 2010)

Your got some sound advise so far. Having said that, there's no way I'd run ply through a drum sander. Most of it's already sanded to 180/220.


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## Phred (Mar 18, 2008)

Here is what I battled. The only way I seemed to cure it was to sand the heck out of it.. not my first option. I think that the next time, I will go straight to 180, and work with the finish from there.

BUT

Am I battling bad plywood? anyone else seen anything like this??


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## BillWhite (Jul 23, 2007)

Looks like a bad skin rash.
Bill


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## Ingjr (Feb 21, 2010)

Woo, that looks nasty. I'd say in this instance it probably is the ply.


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