Drum Sander Question

[Mike Goetzke]

I'm putting my almost new Performax 10-20 drum sander to it's first use on a cutting board project. I'm making the end grain design that was recently published in Wood magazine. The board is approx. 15" long x 11" wide x 1-1/4" thick.

After the glue up I ran the piece through my thickness planer to clean-up the two surfaces. I then ran it through the drum sander starting with 120 grit, then 150, and 220.

This was a good piece to experiment on since it was reasonable size and thick so I had room for error. I did find since I needed to use the two pass method it's best to sand as close to only half of the board as possible. Otherwise a visable ridge it likely.

Now a question for the experts: Even though I used 220 grit for the final passes I still have visable sanding lines in the direction I fed the board. It took more time than I expected to clean them up with my ROS w/220 grit. Is it typical to get these sanding lines or is it because I'm sanding end grain?

(I did pass a piece of oak through the sander and there are no visable sanding lines - this is why I think it's possibly an end grain problem.)

Any help on drum sander technique would be appreciated.


Thanks,

Mike

[Doug Shepard]

It could be an end grain issue. I cant say for sure. I've found on my 16-32 that I can get rid of some of the lines by skewing the piece at several shallow angles and running it through a few times followed by a straight pass - all at the same thickness setting. I think your lines are probably left over from the 120 or 150g belts though. You might try doing the last passes on each of those grits with the multi-pass approach before changing paper to see if that helps.

[Hoa Dinh]

I have a 16-32PLUS but I don't think it is any difference in this regard.

The sanding lines from a drum sander is a given. In other words, you can't retire your faithful ROS.

That is why I've never use anything finer than 150-grit for the drum sander. In fact, I almost always use 120-grit. Then I use this schedule with my ROS (Festool RO150FEQ):

- 120-grit, aggressive mode
- 120-grit, fine mode
- 180-grit, aggressive mode
- 180-grit, fine mode

This is for tight-grained lumber such as maple.

For coarse-grained lumber such as oak, I skip 180-grit passes.

[Charlie Plesums]

On my 16-32 I only use 150 or 180 grit... The jointer/planer does the coarser work. Then I finish sand with the ROS starting with 150 grit.

When I used finer than 180 on the Performax, I still got scratches (like you mention), and often got burning. The performax does a great job, but it isn't a 15 hp unit that substitutes for a planer, nor is it a finish sander.

Oak hides the scratches very well with the coarse open grain... therefore you might want to try a different wood if you are testing for scratch...

[Mike Goetzke]

I probably should have mentioned that the board is made of hard maple, cherry, and walnut. Also, the lines I'm getting are due to the last grit since I turned the board 90 deg to make sure. I can also see now why many only use 120 on the drum sander.

I just finishing up the sanding w/the ROS. The finish on this board feels and looks like glass. I will post pic's after I apply the finish.

Any suggestions on how to finish? I think the article said to use mineral oil.

[Jim Becker]

Drum sanders are not finish sanders...you'll still need to use your ROS to finish things off. Frankly, I don't use above 100-120 grit on mine. Everything beyond that is via my ROS and I also start "one grit down" to eliminate scratches.

[Charlie Plesums]

...Any suggestions on how to finish? I think the article said to use mineral oil.

You can pay big bucks for salad bowl finish and other things with a fancy label, but most of them are largely mineral oil, which should work fine for you. Get it in the laxative section of the drug store, and apply as much as soaks into the wood in 2-3 applications. The key is whatever you use needs to be edible - the amount that gets into food is so small that the laxative effect doesn't kick in.