Bleach damaged table restoration
A customer had been using a spray cleaner containing bleach but the bottle had a break in it. Not realising this it was put on a table. Even with a modern cellulose finish it went through and seriously affected the wood below. In some areas it had bleached the wood, in others it had darkened it. Oak gets darkened by amonia but lightened by bleach. The other challenge with the area that the damage covered was that it was partly on a solid piece of oak and the rest was on a veneered piece therefore meaning that no possiblity of gently sanding it back could help rectify the issue.
To resolve the issue required the use of a strong oxalic acid mix applied with a fine sable brush. The edges of the wetted area then had to be blended with clean water so as not to create an obvious tide mark and distinct line, essentially giving a gradient to the treated area. This was repeated around fourty times to get the darkened area to match with the rest of the surrounding oak colour. To treat the bleacked area a combination of water stains were mixed and tested on a sanded piece of oak before finely settling on the right colour palette and painting in to the damaged area to bring back the colour to match the surrounding oak. Finally when a good resolution to the affected area was achieved the table could be refinished. In this case with a hardy cellulose varnish containing mellamine. Making the table far more resilient to water, alcohol or heat. This was thinned to enable application in the traditional french polish technique which gives a very smooth finish, equivelent to a spray finish which was done in the original workshop.