oxalic acid

[nigelmercier]

It’s only 7 deg C up here in Aberdeen at the moment.

Last time I did the decks (rust stains from fallout) it was 30 degrees, I had a problem stopping it from drying out! All chemical reactions slow down at lower temperatures, so you may need to leave it on for longer.

 

[MM5AHO]

I used my Fiarly liquid / acid mix last winter on the hull sides (out on the dry) at about 3 deg C. Chilly, but scrub harder to keep warm!
It did take longer, but evaporation is less too.
In cold weather, leave for about 20 mins.

Should have mentioned in my recipe above, to make up to 500ml with cold water after dissolving the powdered acid, and after adding the fairy liquid.

 

[dslittle]

Thanks

I mix mine with fairy liquid.
I have a 500ml plastic container. Add two tablespoons of oxalic acid powder, add enough hot water to dissolve, but leave some room for the detergent. Add about 50ml green fairly liquid, and stir gently.

I bought some a while ago and hesitated over the right quantities to use. As a result of this post I got brave yesterday. What a difference !!! The teak looks as good as an expensive commercial treatment last year.

As said, cheap and very effective. Many thanks.

 

[fjweaver]

these are the measures I use

I use 50-60g of acid to 1 litre water - then mix wallpaper paste to your required consistency

I use it on the whole sides below the rubbing strake not just around the waterline – done this the last 3 years with great results