OK guys, here is one to sink your teeth into.

I was advised that the best option for cleaning growth off the bottom of a
fibreglass hull is Oxalic Acid. Apparently it does not damage the glass or
gel coat, but it literally strips any foreign matter on the hull clean off.

Has anyone had any experience with this?
--
Garry Beattie
Ocean Spirit Trailer Sailer &
Small Yacht Cruising Emagazine
www.ocean-spirit.com

Yes, it works. I mixed the acid with water in a bucket, brushed on with a deck
bush, let it sit a bit and then scrubbing. Sometimes it takes three or four
scrubbings to get the slime loose, but time seems to work wonders. Don't let
the stuff dry and you just have to rescrub. Do a few feet at a time, soak
down, scrub, resoak, rescrub, etc.

btw, in case anyone is not familiar with oxalic acid it is sold in hardware
stores as "wood bleach" (read the label as other things are also sold as wood
bleach).

OK guys, here is one to sink your teeth into.

I was advised that the best option for cleaning growth off the bottom of a
fibreglass hull is Oxalic Acid. Apparently it does not damage the glass or
gel coat, but it literally strips any foreign matter on the hull clean off.

Has anyone had any experience with this?
--
Garry Beattie
Ocean Spirit Trailer Sailer &
Small Yacht Cruising Emagazine
www.ocean-spirit.com

FWIW, I've had good success with ordinary bleach in a 50:50 ration to
water. I spray it on, wait a bit and scrape the residue off. For tougher
critters, I use it full strength. I believe it's less caustic than Oxaloc
acid and certainly less-harmful on the lungs. It also costs less and is
far more available than acids.

Whichever you use, make sure to rinse the fiberglass well with water to
remove any residue as well as wear protective gear (I wear an old dive
mask to protect the eyes and a disposable tyvex for the rest of me).
Finally, it seems to me that removing the growth is easer when the growth
is wet - don't let it dry or it'll be twice as hard to remove.

Jax is totally Right, We use it all the time for cleaning the slime off the
bottom of race yachts, its good for cleaning rust stains out too, it seems
to be available in two forms (in the uk at least) either white crystals
which you dissolve or as some kind of wood cleaner (frequently blue though
not exclusively) but protect your self!


"JAXAshby" wrote in message
...
Yes, it works. I mixed the acid with water in a bucket, brushed on with a
deck
bush, let it sit a bit and then scrubbing. Sometimes it takes three or
four
scrubbings to get the slime loose, but time seems to work wonders. Don't
let
the stuff dry and you just have to rescrub. Do a few feet at a time, soak
down, scrub, resoak, rescrub, etc.

btw, in case anyone is not familiar with oxalic acid it is sold in
hardware
stores as "wood bleach" (read the label as other things are also sold as
wood
bleach).

OK guys, here is one to sink your teeth into.

I was advised that the best option for cleaning growth off the bottom of
a
fibreglass hull is Oxalic Acid. Apparently it does not damage the glass
or
gel coat, but it literally strips any foreign matter on the hull clean
off.

Has anyone had any experience with this?
--
Garry Beattie
Ocean Spirit Trailer Sailer &
Small Yacht Cruising Emagazine
www.ocean-spirit.com