Totally agree with Wayne .... you need a 'manly' tool: variable speed
auto body shop polisher with 3M arbor for attachment of 3M velcro
backed 7" sanding discs. A little on the heavy side but will sand off
paint like a hog rooting in a sandpile ... "get it over with and done".
A vibrating 'palm' sander takes 10 times as long to do the same job.

Then you can also use 3M knobby foam pads to buff and polish the
gelcoat too !!!!! .... or the BEST autobody polishing (with 3M
Finese-IT AND 3M Perfect-IT).
Best e-source is probably Jamestown Distributors , although you can
probably find the same thing cheaper if you look hard.

In article , Wayne.B
wrote:

On Wed, 07 Feb 2007 01:32:07 GMT, "NE Sailboat"
wrote:

Is the random orbital sander the tool to use for sanding the bottom of the
boat. What model? What brand? How much to spend?

Any info on bottom of boat sanding?

If you have a heavy build up to remove or smooth, you need one of
these with a 7 inch foam pad and stick on disks:

http://www.hardwareandtools.com/invt/0566349

Anything else is just a toy.

If you are just doing light sanding (but lots of it), this is a good
tool:

http://tinyurl.com/2wdewb

Order extra disks because they can be difficult to find locally.

I own them both and would not part with either.

The small palm sized orbitals or electric drill attachments are
totally inadequate for doing a large surface like a boat bottom.

In article r_9yh.4612$FM3.3257@trndny06,
"NE Sailboat" wrote:

So, I am getting ready for spring. I decided I'd start by giving the boat a
good bottom sanding. I looked in Casey's book, he recommends a high speed
disk sander. Off I go to Sears. I ask in tools where the disk, orbital
sanders are.

Sears sometimes has 5 and 6" sticky-back sanding pads that have a
flexible rubber-mounted spindle. More often, they have a wobble-plate
version that's more expensive.

The flexible spindle and soft pad will remove a *lot* of paint very
quickly with a 60 or 40 grit sandpaper, yet doesn't easily leave
grooves. The drill can be a considerable angle off of perpendicular and
still work nicely. I can quick-sand our bottom in about an hour with
ours. Also works nicely when polishing and buffing with a lambs wool
bonnet.

That's the tool I use for quickly handling broad areas though I have a
plethora of belt, orbital and finish sanders left over from my
woodworking days. I Even have cut wet-or-dry disks and stuck them on to
wet-sand the cove and sheer stripes.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's NEW Pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/

I notice that i the boatyard here in Port Townsend, the sanders that
get used are the big Fein (see Amazon) random orbitals with a powerful
vacuum attached. Since sanding bottom paint can make you pretty dang
sick, not to mention most other living things, the vacuum, which
claims to capture 98% of the dust, is a real advantage.

Aaron Tinling
www.navagear.com - the gear and gadgets blog for cruisers
s/v Sweet Destiny

Aaron wrote:
I notice that i the boatyard here in Port Townsend, the sanders that
get used are the big Fein (see Amazon) random orbitals with a powerful
vacuum attached.
snip

Big bucks, but Fein definitely sets the gold standard if you package
both their vacuum and the 8" sander together.

Lew

Be aware that it is easy to do a lot of damage to your hull quickly
with a very powerful sander. If you have a major peel job it might
well be the best bet to hire a pro. Also some yards will not allow
you to dry sand without an approved containment system, so check with
your yard before you invest in expensive equipment.

I have converted to ablative paint and find that I can prep the bottom
of my 42' cat with a dry wall pole sander and a sheet or two of 40
grit sanding screen in less than two hours. I can't see myself going
back to hard paint for a cruising boat.

-- Tom.