mildew on sail

[dpollitt]

I have just put on my mainsail and to my horror I have found a big portion of it has mildewed......we have had lots of rain and it sat under my cat.....

Any ideas on how I may get rid of it? Also, is it a mistake to now expose it to the sun.....sort of burn the mildew in?

many thanks
david pollitt

[Pblais]

It's more cosmetic than anything. To remove it you want to use the least effort possible. Start gentle before you bring out the flame thrower.

[MidLandOne]

As long as the sail is built from polyester sailcloth, but not otherwise, it is quite ok to soak it in a strong bleach solution.

I have done this a number of times over the years, including on foam luffed genoas, and it both works and does not damage the sail - so in the sense of another thread I can claim experience.

But as some, mostly catamaran owners it seems, are of the view that my experience is actually just opinion made from the comfort of a fireside armchair, and for the confusion of other assorted naysayers I will also point you to the following North Sails web page North Sails One Design to provide veracity - you need to scroll about 1/3 of the way down the page to get to the subject.

If the sail panels were glued before sewing you may find that some mildew staining stays in the glue line, similarly if the mildew is inside multiple layers of cloth at reinforcing.

If there is algae build up in between folds, if the sail was folded when the problem occured, it can be removed by very light soft brushing - taking care not to damage the filler between the threads making up the cloth.

[Wotname]

FWIW, I took my very old (polyester) mainsail complete with mildew and stains to a commerical drycleaner and it came back all shiny and almost new loooking.

[dpollitt]

One further ....the sails is apparently Dacron....this is a form of polyester? and so ok with Clorox bleach?

[Wotname]

Yes, Dacron = polyester; don't know about the bleach

[MidLandOne]

As Wotname says, Dacron is polyester (as is, in United Kingdom speak, Terylene), so it is ok with Chlorox bleach.

Some countries the concentration of bottled household bleach is around 3% whereas in the US it is usually around 5% - just adjust the quantities to suit using the North Sails article concentrations as a basis. It takes quite alot of it.

I have found personally that it works much faster than the 2 - 3 days that North Sails mention and spot treatment works too if one keeps the area wetted while it is working.