Drum sander problem

[Glen01 [OP]]

Hi I hope someone can help.

I purchased a used BB CX509 18/36 open end drum sander. There seems to be a problem with it making the boards flat. There is a are a couple of waves that are created through the length of the board so when I cross cut and try to glue up there are bumps that make a good joint impossible.

Anyone have an idea why this happens and how to fix it?

Thanks in advance
Glen

[gdtrfg]

Your sanding drum may be moving up and down while you are feeding your boards through. Check where it goes from vertical to horizontal, and if that is tight, it’s probably a bearing issue.

[MartyFromKingston]

Glen,

I'd second Paul's suggestions... but there are a few other possibilities what may be causing this problem.

1. ensure you're not trying to use the unit as though it's a thickness sander! These things are designed to take off only a few thou (.005" or so) at a pass. If you try to do more than that, the machine will usually deliver poor results similar to those you're getting, and blow a fuse.

2. check the conveyor table and the belt to make sure there's no sawdust clumped up beneath the belt.

3. it's certainly possible that the bearings on the drum may are shot.

[Saw_Dust25]

it could be the rising and falling of the board going through if you aren't using support rollers that are perfectly level with the feed table. This is a common issue people have when using a drum sander the the table moves up and down as opposed to the sanding head on the CX509. This could possibly be the issue. Is it possible that the work piece isn't properly supported?