weathered wood under worn varnish - oxalic acid?

[maxcampbell]

After an unaccustomed winter outside, before which I neglected to top up the worn areas of varnish on cockpit coamings, etc, I have some areas of blackened bare wood (was OK colour last autumn). I think I have heard that oxalic acid will bleach this back.

Is this correct? Is there anything better? Will it bleach it back to more-or-less the original colour or will it be darker / paler? How many applications, etc? How deep is the weathering likely to go - I haven't tried sanding back yet.

Any other comment (apart from - "you lazy git, you should have done something about it months ago" - which I do realise.)?

 

[robmcg]

Teak restorer?

 

[VicS]

After an unaccustomed winter outside, before which I neglected to top up the worn areas of varnish on cockpit coamings, etc, I have some areas of blackened bare wood (was OK colour last autumn). I think I have heard that oxalic acid will bleach this back.

Is this correct? Is there anything better? Will it bleach it back to more-or-less the original colour or will it be darker / paler? How many applications, etc? How deep is the weathering likely to go - I haven't tried sanding back yet.

Any other comment (apart from - "you lazy git, you should have done something about it months ago" - which I do realise.)?

Regarding the use of oxalic acid see the notes and instructions on the AGWoodcare website. http://www.agwoodcare.co.uk/Item/oxalic_acid