Hi Tom,
A couple of things, which will be heresy to some;
First off, what everybody is talking about is, in the main, big, 11+ amp disc sanders that use a 400mm ( 8 inch) foam pad, which are a lovely production tool and can sand a lot away, fast. But it’s not a beginner’s tool. Again, they can sand away a lot, fast. Especially stuff you really wanted to keep, like the glass and the resin and the first few millimeters of foam.
It takes a fine, experienced touch to get one of 'em to do fine work, like sanding very thin laminates over soft foam. They were basicly built to sand things like heavy paint buildup on steel or polish cars. That they are used to sand and polish surfboards is more testimony to the skills of the sanders than the tool itself. It’s kinda like shaving with a chain saw.
Grinders are meant for grinding steel and general metals, using Very Hard discs turning at Very High speed. Or, with a wire brush attachment, removing rust and crud from metal. As an aside, I got a cheap one for the restaurant I was working in this summer, it was and is lovely for getting the smeg off the cast iron grills we grilled fish and chicken and stuff on, got it down to nice white clean metal in seconds rather than hours by hand with steel wool scrub pads.
But they’d eat surfboard glass alive. Maybe useful for coarse shaping of solid glass fins, but beyond that, no.
Now, you have been using an orbital sander, probably one of those that uses a quarter sheet of sandpaper? Or perhaps a half sheet. Also a good tool, but it was meant for doing finish work on wood and furniture and that sort of thing. It won’t hack away a lot of material fast, it’s not meant to.
Enter the Random Orbit ( or random orbital - the terminology is a mite confusing) sander. Typically they use a 250mm or 300mm disc of sandpaper, They don’t spin like the big discs, nor do they vibrate like the orbitals. They can remove a fair amount of material, with an agressive grit disc, and they can also be toned down with low RPMs and finer paper to do a nice, finish-quality job.
‘Will it perform for a backyarder?’ Hell yes. It won’t do it nearly as fast as a 13 amp Milwaukee or other 8" disc sander, but that’s fine - your chances of ruining your glass job are also much less. It’ll work a lot faster than the orbital. I used one exclusively for years, doing lots of ding work. Only got an 8" disc sander/polisher when I found myself sanding lots of broken boards, lots of boats and I happened to have $200 US I wasn’t doing anything useful with.
The model I use - granted, mine isn’t nearly as pretty now…
A few things to look out for, though:
I’ll note that the one you show has dust collection in it from the get-go. All well and good, but the glass and resin dust will do it no good, especially as the thing uses motor air to push the dust into that silly little canister filter. Use sandpaper discs with no holes in them, and brush, blow or vaccum the dust away as you’ve been doing with your orbital.
See how that one is set up; in theory you can use it one handed. Don’t. Your control will suffer and worse, your hand will block those slots up top that supply motor cooling air result, fried tool. Use both handles - buddy of mine has been using a similar Bosch for years with good results this way. Put it another way, palm-grip sanders suck for anything but the most dinky, home handyman work.
Avoid sanders that will only use hook and loop paper - like a Velcro backing. Not only are you nailed to what the makers supply ( can’t make your own discs in non-standard grits and all) but the damned things are expensive. The theory is that you can switch paper and reuse the ones you took off - nice for Joe Homeowner sanding a 1’ x 1’ area from coarse down to fine but it’s downright silly for anybody doing any real sanding.
Use press-and-stick sanders. The discs are cheap enough that reuse isn’t an issue, or have some wax paper to stick the used discs to.
Also, never be afraid to chuck a disc when it starts getting dull and heating things up rather than cutting cleanly. Paper is cheap, bubbled glass isn’t.
Anyhow, that’s enough to be going on with. Hope that’s of use…
doc…
