Cleaning black mould spots from wood?

Morning all.

Some Teak wood on my boat isn’t looking great after a winter outside. I think it’s picked up some mould spots, seen on the photo below.

I think the answer is to sand it down as best I can, unless anyone has some other bright ideas?

I get lots of this on the hardwood garden furniture … normally I oil over the top and it seems to do the job.

IANAWWE

@kayak23 and other types will probably give much better advice.

PS – you probably need to line up all your screw heads there 😉

following. I sanded down and painted over a windowsill the other week and the paint has come off with an impressive pattern of mold under it.

Oxalic acid is, I believe, the answer here. That will remove residual staining after you’ve sanded or scraped the varnish off. I’ve never used it on teak, usually oak, but a quick google suggests oxalic acid is still the right answer for teak. Just avoid getting any on your shiny metal hardware, may tarnish it.

Cheers All.

I’ve removed the doors for cleaning Reeksy, so will ensure better alignment of screw heads when I refit 😉

Try and avoid sanding, or you’ll have nothing left in a few years!

Yes, oxalic acid or a proprietary teak cleaner once any varnish has been scraped off. Brings it up lovely!

Anothe rvote for oxalic acid, we used it to clean tea outdoor furniture after reading that it is the standard for cleaning teak decking on boats.

Oxalic acid did indeed do the trick, thanks all. This is after 2 passes with medium strength, might give it one more pass.