Repair exterior painted shingle siding
The owner previous to me used a grinder (probably in a drill) to sand cedar shingle siding that has been painted.
He put lots of grinder gouges and circles in soft shingles. I have been filling those with a exterior product "MH Ready Patch" a Zinsser product. I need to sand this smooth to correct grinder gouges. I have tested a chunk of paint that came off and it was lead based paint originally used back in the 60's. I am concerned about the dust even though I am trying not to get into underlying paint. I am using an Milwaukee Orbital sander that has a dust bag on it and have a NOSH mask to wear. Am concerned about breathing lead dust should I hit a high spot or get into underlying paint while sanding using a 50 grit sanding disk.
Any advice or help would be greatly appreciated.