Dressing a Widebelt Drum with Sandpaper

A detailed discussion of using sandpaper glued to a wood platen to return a widebelt sander's drum to useable condition. July 29, 2012

Question
I had a professional equipment maintenance guy fix my Time Saver drum years ago. This is a new drum and itís scarred again. We are too tight on money to have a professional do it, so we will have to do it ourselves. This is what I remember of the process:

1. We had to bypass a couple of safeties in the machine to get it to run without the feed belt in operation.

2. We made a wood platen the width of the machine out of 3/4" MDF and glued 150 grit or so paper to it.

3. We ran the machine and raised the clamp and secured a piece of MDF up into the drum. So the drum was basically dressed running by contacting the sandpaper on the MDF.

Is that about it? Any tricks or safety issues?

Forum Responses
(Solid Wood Machining Forum)
From contributor P:
We did what you described and it worked well. I don't remember having any problem.



From contributor D:
Heavier grit is less liable to grab and chatter. Be sure to use the handwheel for the smallest movement possible when incrementally moving up the bed. New silicon carbide (black) sandpaper cuts much better too.



From contributor G:
Mine also needs doing. I spoke to the repair guy who said that rubber needs to be a minimum of 1/2 left on the drum. If less than 1/2, the drum will need to be resurfaced. Is this true? Can you just feed the sheet of sandpaper/MDF through instead of trying to hold it in one spot?


From the original questioner:
We finished it yesterday, and it worked great. We started with 100 grit. It loaded the paper quickly, and we had to reposition the board several times to get a fresh cut of sandpaper. All we did was take a 100 grit belt and a 220 grit belt that had glue marks on them and cut them up to glue to the MDF. We used 3M spray glue to adhere the sandpaper.

We made the 3/4 MDR full width and the length of the feed belt. We then took a piece and screwed to do the back side of the 3/4 to let it hand over the out feed side of the machine. Just in case it grabbed it and tried to pull it in, which it did.

We did it with two people. One lowering the machine by the hand crank and another watching with his hand on the Estop.

Once we got rid of the scares, we changed the paper to 220 grit to make sure the drum was clean. I am sure there is at least 1/2" of material left on the drum.

We then reset our platen just below the front wheel. Once we were happy with the cut, we took an allen wrench and reset the digital scale on the side of the machine for depth of cut.

All and all it was fairly simple. Donít get in a hurry or you will mess something up. It seems a bit scary at first, but the machine ran smoothly and it did not create any problems. We stopped every couple of minutes to suck the rubber drum bits from inside the machine, so we would not end up cutting them again.

Very happy with the overall result. We now have a flat drum. We are sure the machine is calibrated side to side for a dead even cut, and the scale is correct again.



From contributor G:
Looked at my wide belt again. The first drum, the grooves are a bit over 1/4 deep. If I just go for it and dress the drum as described above, what will the effect of a shallow groove be? Do you dress both the front and back drums at same time?


From contributor D:
You have to be more careful than contributor J, I think. A whole quarter of an inch is serious. I'd really only want to take off a hair, 1/64" or so at a time. The wider your sander is, even less so. MDF gets hot and swells like hell too, so keep cool and let her breathe. Small moves. Bad stuff happens if you get in a hurry. Front and back should be alike on two heads if your sanding platen stays flat (don't overheat).


From contributor J:
If your bed is off slightly to the head, will this matter? Or will it grind it true to the bed? I think our bed is off about .050 on a 36" machine from side to side and not sure if bed is off or head is worn.