varnish problem

[ed1hosea]

Hi.
I am hoping for some help with a problem I have had. A solid wood windom sill in conservatory had developed black mouldy stains. The only way I could think of getting rid of it was to completely strip down to bare wood, sand and revarnish, which I did using a good 'clear' varnish. This made the wood darker than before and it now looks totally incongruous with the surrounding skirtings etc. I originally thought the wood was a beech or oak (very light colour, which is what is wanted) but turns out it is mahogany (this threw me as I associate mahogany with darker colours?). I accept I will have to go back to the bare wood again but what do I use to varnish / laquer so that it doesn't darken the wood and provides a good tough durable coat??
All help will be much appreciated.

Eddie

 

[mrpercysnodgrass]

Hi Eddie,
If your sill is made of Mahogany, the darker colour you now have is not due to the varnish but is the natural colour of the Mahogany. There are two way to make it lighter, one is to bleach with hydrogen peroxide using a two part solution pack. This method will work well, however I would not recommend it unless you have experience in using it as you have the danger of going too light and then your sill would still not match. The second solution is to allow the sill to bleach naturally, it should not take too long in a conservatory, probably by the end of the summer.

 

[ed1hosea]

Hi. Thanks for this response. Unfortunately it is the varnish that causes the darkening as the unvarnished wood is already light. I could try the peroxide bleaching but I am sure it will still go slightly darker when varnished. The sun bleaching idea would be good if we actually got some but living in Scotland means we hardly get any.
Thank again

Eddie