Drum sander versus Belt sander for large pieces (a shop review)

So I convinced my wife of the sacrifice I would make by building a drum sander. Recently I did a large dresser top with the belt sander method and four smaller tops with the drum sander, here is what I think of the methods…

The drum sander is a 30” stockroom supply kit, with a 3hp sealed 3450 RPM motor purchased seperately, I used a 4” pulley on the drum and a 2” pulley on the motor to reduce the drum down to 1725 RPM as called out by SRS. The pullies came from Grainger. The table top is 24” x 40” with the groove cut in the middle for the drum.
http://lumberjocks.com/projects/9205

Doing small tops (24×36”) on the drum sander is pretty easy. I used 16 lbs pavers to help keep a distrubuted load and pressure on the wood as it passed over the drum. Starting with 80 grit, to 150 grit and finally to 220 grit. The top came out very smooth, flat and even. I did not sand out the joints prior to going on the drum sander so I spent about 2 hours per side on the 80 grit, about 30 minutes per side on 150 and 220. The thing to watch for is as you play the top back and forth over the sander, where you pause to go from push/pull or vice versa it creates low areas in the work. Making several passes over this transition area at the end cleans up these areas to create a uniform surface.

Here are the tables done with the drum sander:
http://lumberjocks.com/projects/8916
http://lumberjocks.com/projects/8767

After finishing with the 220 on the drum, I switched over to the 5” Random Orbital and spent another 15 minutes each with 350 and 400 grit, followed by the 500 grit to get the shiney finish. Each top took about 4 hours total of sanding with this method and this method had the flattest and most even thickness finished top.

The large dresser top I did with the belt sander. The glued up piece was 24” x 68” and since I don’t have a tension fence on the drum sander yet, I opted to clamp it to my work table and belt sand it at 60 grit. It took about an hour to get each side belt sanded smooth and even. At this point I switched to only sanding the top side to finish grade. It took 3 hours with the RO sander at 100 grit to remove all the scratches and low spots in the top. If I had higher grit belts this might speed up, but I only use the belt sander for very rough sanding. Another 30 minutes with each: 220, 350, 400 and 500. So about 7 hours of sanding time with this method to do only the top side that you can see, but the top is twice as big as the drum sander example top. There was a lot of time spent sanding out low and uneven spots left by the belt sander that the drum sander would have eliminated up front.
As soon as the dresser is completely finished I will post the project. I glued up the last of the drawer fronts yesterday so today should see final assembly and first coat of finish applied.

In conclusion I prefer the drum sander method for time and finish and will be setting up a tension fence to hold the work down against the drum so I can do the larger tops on the drum sander.

-- Rich, WNY, www.nyrockingchairs.com