Forgot to mention .... if you use this on-the-boat method dont let the
caustic get onto any bare teak or teak covered with an oil finish.
Such caustics will immediately strip the oil and start etching the bare
teak.

..... or if you want to, you can clean the sails and clean the teak all
at the same time (just dont let the tannin extraction from the teak get
onto the sails while you're cleaning).

In article , bilge
wrote:

thank you.

On Sat, 05 Mar 2005 15:09:59 GMT, Rich Hampel
wrote:

Any higly caustic detergent will 'dissolve' the mold. Its probably
'artillery fungus' - a mold which comes from tress during wet weather.
Its also those 'teeny black specks' that 'appear' all over gelcoat.
Caustics are compatible with WHITE dacron and dacron laminates.

I prefer sodium silicate based detergent - buy it at a janitorial
supply; sometimes you can find it at West Marine or other chandleries
under the brand name "Tuff-eNuff". Tuff-eNuff is made in Florida and
is common there and on the east coast.
Be sure to rinse it thoroughly.

For any tannins or rust/iron stains remaining use oxalic acid, and
rinse thoroughly. Dont mix caustics and oxalic !!!!! ... do each stage
separately with copious rinsing in between. (Use oxalic to remove the
tannin/iron 'moustache' on the bow and waterline.) Cheapest source of
oxalic is from a hardware store - 'wood bleach'.

Clean the sail ON the boat, slowly raising the sail while spritzing the
stuff on @ full strength, let soak and mist with water and scrub with a
soft brush, drop to deck and cover with a plastic tarp to prevent
drying then raise again while scrubbing. Use a garden hose to rinse,
and rinse and rinse and rinse and rinse. Best is to do it on a
windless, cloudy and humid day .... then go sailing to dry the sails.

Any detergent that spills to the deck will dissolve all the old dead
wax thats down in the pores of the gelcoat .... so its time to rewax
the boat! Artillery fungus when it appears on gelcoat is probably
'eating' the wax in the pores of the gel - once the dead wax is
extracted you will have fewer 'blooms' of artillery, etc. fungus.
Obviously you done want to do this ON the boat if you have a teak deck
as the caustic will dissolve the tannins, etc. in teak !!!!!! Note:
caustic detergents will very temporarily discolor gelcoat and turn it
briefly yellow until all the dead wax dissolves - dont panic as it will
come back to color in about 15 minutes. Two jobs all at once. Once
the dead wax is extracted, rewax to seal the gel pores.

Wear protection when using caustic detergents as they will dissolve
your skin, eyeballs, etc. Oxalic rapidly absorbs through the skin and
can do GREAT harm to your kidneys ... use gloves, etc.



In article , bilgelick
wrote:

Any way to remove these disgusting black mold spots from Dacron sails?
Some of the sails are old and some new but all are plague ridden.
Thanks again.