Tweaking a Woodmaster Sander

Advice on how to get acceptable sanding performance out of a small multi-purpose machine. January 19, 2011

I have a Woodmaster planer/molder and supposed drum sander too. I'm having trouble after trouble with the sanding paper not being flat on the drum. I fight it, putting it on over and over, trying to get it flat. Once I finally get it on good, it ends up tearing and throwing the paper within a few boards, ruining the Velcro with it. It's getting expensive to learn this way, and I'm tired of ordering extra stuff. I don't think I'm taking too much off - light passes with 150, no more than 3/32, and medium to slow speed. It's not bogging down at all. I would expect it to be able to work harder than how I'm using it, but the Velcro paper system just keeps failing. Any tips? I guess it's back to the RO till I feel like ruining the last piece of Velcro I have.

Forum Responses
(Cabinetmaking Forum)
From contributor S:
I have a 25" General and it doesn't use Velcro, but 3/32 in a single pass is way too much. Think more like 1/32 with 150 grit, or even less. I use mine mainly to level 5 piece doors, and 3-5 passes with 100 grit start is more the norm.

From the original questioner:
I meant 3/64, and that's the heaviest, not the normal I shoot for. I think my problem lies mainly in the Velcro. I had a JET for a few months and it didn't use Velcro, but was way underpowered. Sold it and got a Woodmaster to save space, but every time I try to use the drum sander, it ends in disappointment and going back to a hand sander. I'm not even sanding wide stock, just maple boards mostly under 6" wide, to get rid of tearout and marks left by planing. 5HP should be enough to remove 6" x 1/32 at a decent speed, right? My old sander self regulated the speed when the motor was fully loaded, and I'm not trying to push it much harder than I used to push the JET that had 1.75HP. I see many machines using the Velcro method for the paper, so is it that bad of a system?

From contributor J:
I have the 38" Woodmaster drum sander and I had similar problems. Seemed like I went through a lot of paper/Velcro mats for the results. I was using the cheapest paper I could find. I switched to Mirka rolls and it made a huge difference. I noticed when using the cheaper paper, the paper and the felt back would separate when it got hot. The paper would start to creep or ball up and cause problems. I don't seem to have that problem using the Mirka paper. Also make sure you have proper dust collection, as I had to upgrade mine when I got the 38 sander.

From contributor K:
I am happy with my Woodmaster. To remove material, I use 80g paper. 150 is just to clean the sanding marks. I usually go 80 first and then 180. And yes, it still requires a touch of hand sanding, but not a lot. As for planing, I don't do much anymore. I can buy it S3S from my supplier for 15 cents a board foot extra, and that's a no-brainer. I buy paper from Woodmaster and good DC is a must.

From contributor D:
Sounds like you're trying to take too much off and too fast as well. Those Woodmaster drum sanders are slow if you want them to work.

From contributor Z:
When you are wrapping the paper on the drum, are you leaving a gap between each wrap to allow for some expansion?

From the original questioner:
No, I wasn't leaving much of a gap. That could be it.

How big of a drum sander or widebelt do you need to remove 1/32 at 20fpm or so? That's what I would like, but I bet I'm only running around 10fpm. I like my Woodmaster - I would by it again considering my space restrictions. It's just been a pain getting this function of the machine to be productive. I think the claims they make in the brochure for it are a little ridiculous, but I think I have a pretty good understanding of what it should be able to do.

How flat should I expect the boards to be after sanding with a properly wrapped drum? Are some high and low spots on the drum normal?

I get my paper from Woodmaster. I haven't seen Velcro backed rolls anywhere else I shop. I couldn't even find any info on such a product on Mirka's website - what's the product called?

From contributor E:
My experience is with a 5 hp Powermatic dual drum sander.

First, you're trying to take off way too much material. You cannot measure the amount of material you can remove with a single pass at 150 in maple. Well maybe using a mic, but certainly not with a tape measure or rule. 150 is much too fine for removing material, especially in a hard material like maple. You need to drop down to something like 60 or 80 grit.

My machine had rubber drums and I never had any problems tearing sandpaper. I don't have any experience using Velcro, but seems like it would tear easier since there must be just a bit of sponginess between the paper and drum?

I now have a 43" Timesaver with a 25 hp motor and I still don't try to remove a full 1/32" in a single pass with 150 grit. I suggest you try lighter passes using coarser sandpaper. 150 grit should be your final pass before going to the ROS.

From contributor V:
You are expecting way too much stock removal per pass. We run a 15 hp wide belt and remove up to .015" (1/64") with a coarse belt (60-80#). Any more and the feed motor stalls and leaves a divot in the panel. Fine grits must take much less to avoid burning -.010" for 120#, .005" for 180#. Concentrate on getting a cleanly milled surface first, then use a coarse grit to remove tearout, then use finer grits to refine the surface, taking only enough off to remove the coarse scratches from the previous grit. This will take the least power and conserve your abrasives. Taking a large jump between grits, like 80 to 180, means more passes to remove the coarse scratches. Starting at 150# to remove significant tearout means more passes and shorter abrasive life. This is the drawback of drum sanders with their laborious grit changes. If you can, upgrade to a wide belt - better results, less work changing grits, and takes up no more space. A digital height readout would be a good investment for any thickness sander.

From contributor G:
Contributor V is right. 150g can only remove about .005" on a widebelt. Maybe even less on a drum with a fairly small diameter. Woodmaster's drum sander has a 6" drum but the planer moulder's sanding drum is only what, 3" or 4" in diameter? You can only move the elevation crank a small bump at that rate. It is still faster and flatter than using hand held sanders.

From contributor M:
I used to own and operate a Woodmaster and once we got the hang of it, it worked well for our sanding. We did not do a lot of sanding, so the slow speeds were okay with our setup. Be sure the Velcro on the drum is clean of chips and dust before attaching the paper. Be sure you pull the paper tight as you attach to the drum. We never left gaps in the paper, always had it meet edge to edge. Wrap both ends of the sandpaper with reinforced package tape - the clear, narrow kind with the fibers used for packages. We did this to keep the ends from coming loose and letting the paper unwind. The tape was only 3/4", so it did not interfere with the actual sanding area of the paper. If the Velcro has overheated or separated from the drum, order some more and replace it. Run your hand down the drum and see if the Velcro has bumps or loose areas. If so, it has separated from the drum and will only cause problems.

From contributor B:
This may not be an option, and I know it won't fix your immediate problem, but based on experience, I would suggest you start saving for a belt sander. They cost a little more, but are worth it in the long run. No Velcro, no wrapping paper. I can change belts on my Grizzly in less than 30 seconds. Nothing was more frustrating than the ominous sound the drum sander would produce just before the paper tore completely through... then... wap, wap, wap. 20 minutes later, you are up and running again and able to finish your board. At $50 an hour shop rate, you just wasted approximately $17, plus the cost of the paper, plus time that could have been spent making money. A belt sander does not take long to pay for itself.

From contributor A:

Inadequate drum sander dust collection can cause overheating, which can cause delamination of components, as well as other problems, including belt stretching, dust loading, burning, etc. For your machine, at least a 2HP 6" inlet dust collector, and at least a 6" fitting at the drum sander, is a minimum setup.

Also, check the parallelism of your drums to table, or drums to conveyor, whichever you have. If out of parallel, you could be taking off a lot more on one side than the machine can handle, in addition to unevenly surfacing your stock. I have a 26" Steel City that came, it turned out, out of parallel. A phone call to tech support and some adjustments got the unit parallel. The sander has become one of the most versatile and hardest working machines in my shop.

From contributor Q:
Pretty much everyone has it right in their replies about the Woodmaster. I have the WM 24" (about 7 years old now). One complete turn on the crank will give you 1/16" in elevation change on the drum. I will generally only give it a quarter turn (or less) per pass, and feed it slowly! Too fast and too much cut will give you exactly what you have been experiencing!

The panel should be flat, but of course there will be sanding marks depending on the grit. And no, highs and lows are not normal on the drum with proper setup. Don't push the Woodmaster beyond its comfort zone and it'll do the job just fine!