Join Date: Jul 2000
Thanked 236 Times in 223 Posts
Rep Power: 18
Re: Sail Cleaning
Ive been lofting and making my own sails for well over 35 years. I also spent my initial engineering years in textile processing equipment.
If the sail is made from woven dacron polyester - NOT for colored woven dacron, NOT for sails made of 'laminates', etc. :
First extract the 'dirt', do this ON the boat (if and only if the boat doesnt have
BARE teak decks or trim)
On a cloudy windless day .....
Slowly raise the sail as you 'spritz on' detergent (and water) made from either sodium silicate (eg. Tuff e-muff ... mfg. by Wallace and Sons, Ft. Lauderdale Fl .. expensive) or mild trisodiumphosphate (TSP) solution
Use a SOFT scrubbing brush mounted onto a long 'telescoping' painters pole; raise the sail as you go to 'spread' the detergent equally.
When the sail is fully 'up' and full 'spread' with detergent ... drop the sail onto a plastic tarp and then cover with a plastic tarp and wait for at least one hour to 'soak'.
After soaking, slowly raise the sail, scrubbing as you go, and re-spritzing areas that became dry.
Drop the sail and cover and let soak for approx. another hour.
If the sail is 'really' dirty you may need to raise and scrub then soak several times ... usually not needed.
Slowly raise the sail as you rinse both sides (with a garden hose) ... raise and lower several times while rinsing.
The sail will now have most of fungus (usually artillery fungus - the 'black specs'), air pollution, general 'dirt', etc. removed. The next step is bleaching.
Bleaching - removal of tannins and rust:
Thoroughly rinse ALL the sail material, deck, scrubbing brush and YOU of any 'detergent'.
Take the contents of crystals of oxalic acid (paint store stuff) and put into the bottom of CLEAN bucket, then add 'just enough' warm to hot water to cause ALL the crystals to dissolve.
Don rain gear, goggles, gloves (Oxalic acid readily absorbs through the skin and is 'concentrated in your kidneys' ... forming sharp crystals .... kidney stones are accumulations of principally oxalic compounds)
Apply oxalic acid mixture to the whole sail to remove tannin stains, rust stains, etc. ... usually the oxalic acid application will 'instantly' remove the staining.
Raise and lower while rinsing the sail ... you must remove all the oxalic.
When fully rinsed, raise the sail to fully dry before lowering.
Dacron polyester and dacron polyester stitching is a VERY stable and chemical resistant material .... old clothes made of dacron polyester will be in landfills 600 years from now and will probably look the same then as now because of the 'stability' and chemical resistance of the material.
BTW - now re-wax the entire boat as the 'detergent' you just used 'stripped' most of the wax you previously applied to the gelcoat, etc.
DO NOT "IRON" the sails.
DO NOT put the sails into a kiddy pool and stir them with an oar, you'll only break down the heat-calendered 'filler' between the weave, etc.
Do Not attempt to clean sails on any surface that cant be totally cleaned beforehand, certainly keep a new/cleaned sail away from 'ground/dirt'/tree leaves, etc. ... dacron is a 'dirt magnet', and thats why you just cleaned it.
Last edited by RichH; 12-05-2012 at 09:35 PM.