I'm trying to clean up some floor boards to assess their suitability as
an exposed floor surface. They're pretty ingrained with what I guess is
plaster dust, blobs or artex and assorted grime. A belt on my sander
will clean about 6" square before losing all its abrassiveness, it's not
just clogging. Any suggestions for any kind of pre sanding treatment, or
do I need to bulk buy some more sanding belts?