I haven't used my angle grinder yet, but i did have good luck with a air- powered die grinder equiped with roll lock disks

: With great relief and satisfaction I looked at the hull of my Cosine Wherry
: rowboat and saw it well sanded. It had been hours and hours of dull and
: mostly boring planing, scraping and sanding but it was finally done. The
: feeling lasted only until I turned it over and saw this big yawning
: 52" beam wide inside of the hull. That's when I felt like giving up.
: How was I ever going to sand this huge concave?
: Well the hell with scrapers, planes and random orbital sanders. I drove to
: the store and bought myself a nice lightweight 5" angle grinder and a
: hard plastic backingplate and a quantity of #80 and #120 sanding pads. It
: took a few minutes to get used to this 10000 RPM baby but it's a treat. Ok
: it's not for the fainthearted but that goes the same for the many extreme
: sports today. There is nothing dull(sic) about sanding soft WRC strips
: with an angle grinder. Instead it keeps you totally focused with all your
: senses all the time. If not, goodby boat.
: The secret is to have a good grip on the grinder and softly, softly stroke
: the wood once or twice and it's smooth. It's a bit like stroking a pussy
: cat. I finished the whole inside of the hull in about 4 hours compared to 20
: hours or more of convential sanding. WARNING to FIRST time builders. Don't
: use an angle grinder to sand your boat. It's dangerous.
: Anyone out there uses an angle grinder to sand the inside of the hull?
: William