Green stuff on sails

bluedragon

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I unwisely left my roller genoa furled on the boat all winter, and when un-rolling it in Spring I found I had green algae stripes all over it where water had got down inside the rolls and sunlight had done the rest. I cleaned the sail on the pontoon with hot water, detergent and a brush, hosed clean, dried and then re-installed on the roller. Haven't used the boat for a some weeks, and today I noticed to my dismay the green stuff is still there (or it's come back). I'm going to get rid of this tomorrow somehow, but wonder if there's any suitable cleaner as I'd rather not go down the bleach-and-brush route that I know will do the job, but might not be the most user-friendly solution for the sail and stitching!
 
Had the same on our canopy and could not get it clean.

I then tried "Renovo" from a Chanders, its about £10 per bottle. Put it on with a sponge and left it for 1/2 and hour then used a strong brush and a hosepipe to remove the green slime-monster that remained.

Looked very well afterward and it has not returned after 3 months.
 
I seem to remember from school science in my very early years that acetone dissolves chlorophyll which is the green stuff, so it will probably work. We used acetone to remove the sticky letters from the sails when we changed the name. It worked OK and did no harm though buying it from a chandlery is a mug's game, terribly expensive. Here in Spain it costs less than €3 per litre in any supermarket so shop around before paying £8 for 750ml!!

It is horribly inflammable, beware!
 
If the sail is polyester then household bleach is fine (and cheap). Just use it in the quantities recommended for clothing on the bottle and soak as they say - fortunately, the only time I had to do this myself we had an enormous bath which would take a 500 sq foot sail and a massive balcony to hang it off to dry /forums/images/graemlins/smile.gif. If no container big enuff, then sponge it on, and if any brushing must be soft and gentle to avoid damaging the filler in the cloth.

Then final wash, if desired, in laundry detergent.

If the sail is not polyester, get some advice from a sailmaker (or give it to them to clean).

John
 
PVB gave excellent advice which he got from Hallberg Rassy for treating green algae on teak. I also used it on my genoa 2 years ago and all the green has gone.

Use one of the products for killing mould prior to decoration. They contain 3%w/w disodium octaborate (a fungicide) and 1.5%w/w benzalkonium chloride (an algaecide). B&Q stock Polycell 3-in-1 Mould Killer; it costs about £5 per litre.

I spread my sail out on the grass and used a sponge mop and paint tray to hold the fluid. It can be applied sparingly and I applied it on both sides of the sail (don't know it this is necessary). The sail does look a bit grubby but not green!

Also great for ropes that have gone green. Takes very little fluid and it wicks through the rope.

I would avoid bleach as it might shorten the life of the fabric.
 
I would avoid bleach as it might shorten the life of the fabric.

I suspect that you are giving advice based on assumption rather than knowledge.

As I said in my post, bleach is fine for polyester - you will even find it recommended as being so on sailmaker's sites. I keep having to hunt them out for silly disbelievers of cat type advice, so here is North's one for you to consider http://nsweb.itinfo.dk/uk/sailcare.asp - scroll well down the page to see the cleaning advice for polyester sails.

I have used it myself.

John
 
[ QUOTE ]
I suspect that you are giving advice based on assumption rather than knowledge.

As I said in my post, bleach is fine for polyester - you will even find it recommended as being so on sailmaker's sites. I keep having to hunt them out for silly disbelievers of cat type advice, so here is North's one for you to consider http://nsweb.itinfo.dk/uk/sailcare.asp - scroll well down the page to see the cleaning advice for polyester sails.


[/ QUOTE ]
You are right - I have no experience of bleach damaging sails. My comment was based on a recollection that bleach can damage some plastics.

Thank you for your link to the North site. It is useful to know from a reliable source that it is fine to use bleach on polyester (but not nylon or kevlar) but you must rinse it well afterwards.

"After washing with bleach, always rinse thoroughly with plenty of fresh water. Bleach that is not removed can cause long-term structural damage that is more harmful than the cosmetic damage caused by the mildew."
 
Regarding the rinsing - Yes, as I said, just follow the directions on the household bleach bottle for clothing and all will be fine.

John
 

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