I was wondering if anyone could help me I have a galaxy drum sander all of a sudden it is leaving chatter marks and I can't figure out why the guide rollers one was no good so I changed it and still get them cleaned the wheels still there help please

Chatter and waves are two different things that cause them, but can look very similar.

A lot of pressure and too much speed, along with going the wrong direction(drum vs. belt) is usually the cause the chatter.
Although a bad belt or fan bearing, bad paper can cause it.

Wheels out of round or with build up, loose flooring, a bump that never got flat from the angle cut, or an inconsistent power supply, are the usual causes of the wave.

Are they ¼"-1 inch apart, or 2-4 inches apart?