Variable rate disc sanding
In case you haven't thought about this recently, the aggressiveness of your disc sanding efforts can be controlled by a lot more than just the grit of your sandpaper. That additional factor is the SPEED of your sanding disc.
For Shopsmith MARK V owners, this can be easily controlled by merely turning your machine's Speed Dial to a lower RPM. This will reduce the aggressiveness of your abrasives - and minimize burning, as well.
BUT…you can actually do this without ever touching your Speed Dial . How ? Simple.
We all know that one of the secrets to successful disc sanding is to always be sure your stock is making contact with the disc on the down side of the disc. Failure to do this will result in the workpiece being lifted off the table surface. What many of us forget is that the farther our contact point is from the center of the rotating disc, the higher our Sanding-Feet-Per-Minute… and with that, the aggressiveness of the sanding process.
…Move your contact point farther away from the center of the disc for higher Sanding-Feet-Per-Minute numbers and therefore, more aggressive rough sanding operations.
…Move your contact point closer toward the center of the disc for less aggressive, more easily controlled finish sanding.