Wet Sanding: What did I do wrong?

[Audios S6]

Looks like primarily defects instilled by the rotary with a few RIDs and pigtails that weren't gotten out. I would say you are done with bulk sanding on this panel and you did a pretty good job, maybe some spot sanding left if the rotary can't get those few RIDs and pigtails. Then consider either an intermediate step after wool and rotary or changing up your finishing step. Some folks have had problems with the 3401 leaving a less than perfect finish on soft paints, and your fresh clear is most likely on the soft side.

[EXTJosh]

Looks like primarily defects instilled by the rotary with a few RIDs and pigtails that weren't gotten out. I would say you are done with bulk sanding on this panel and you did a pretty good job, maybe some spot sanding left if the rotary can't get those few RIDs and pigtails. Then consider either an intermediate step after wool and rotary or changing up your finishing step. Some folks have had problems with the 3401 leaving a less than perfect finish on soft paints, and your fresh clear is most likely on the soft side.

Thank you (love your site btw)...


So everyone was spot on...It was a combination of not sanding with a low enough grit to start with and poor technique/lack of experience with the rotary. I think with the rotary I also have a cheap wool pad (as suggested) that was doing more harm than good. I backed down, doing 1500/2000/3000/5000 all by hand, then finished with M105 and my Flex3401 and the finish came out great (minus the 1500 hand sanding scratches I didn't see throughout the process). When I tested it with the rotary, there were TONS of nasty swirls and scratches from the wool pad--not to be confused with buffer trails or compounding haze.

Now that I've isolated the problem to the sanding (I'll hopefully be able to use the Flex for compounding the 5000 grit), I'm having a friend of the shop who does body work come by this afternoon to take a look at my sanding techniques to help me get a better finish. Thank you again for all the input, you all have given me the ability to narrow down exactly what went wrong. I'll hopefully have pics up soon of the finished results!