Kevin Woods from Dublin writes: “I have a 1991 Feeling 286 Special. Some of its timber interior is stained by black lines in the grain – as you can see from the photo of the main cabin door – presumably from having been damp over one or more winters. What are my options to remedy this?”

PBO woodwork expert Colin Henwood replies: “The first task is to carefully remove the old coating and expose the plywood top veneer.

“This could be done with a chemical stripper or a hot air gun and a scraper – with both techniques there’s a risk of damaging the veneer so take care.

“The aim is to remove all the old finish and end up with an even overall colour given that the damp has discoloured the wood where the grain has moved. Do the best you can.

“Next sand the surface ending with 180-grit paper, the starting grade will depend on how well you got on removing the old finish.

Article continues below…

Leaky boat repair: How we plugged the gaps in the PBO Project Boat

Leaky portholes and portlights are common on cruising boats, but there are several things we can try to solve the…

What’s the best boat paint for topsides? Ask the experts

PBO reader David McDermott of Saundersfoot, Pembrokeshire asks: “Because of the Coronavirus pandemic we didn’t put our Prospect 900 into…

“If it was a good, clean job start with 150-grit; if not so good start with 120-grit then go on to 150-grit. Again, be very careful not to sand through the veneer! A regular vacuum off to inspect the surface is critical.

“To remove the black stain use an oxalic acid solution such as Liberon wood bleacher. This needs to be washed out of the wood with plenty of water.

“The water will raise the grain so rub down again, this time with 240-grit paper on a cork block to leave a perfectly smooth surface.

“Before starting to apply new varnish check the surface for any cross scratches or imperfections that will grin through any clear coating and torment you for years to come.”

Got a question? Email pbo@futurenet.com and we’ll put it to one of our experts.

Why not subscribe today?

This feature appeared in the March 2023 edition of Practical Boat Owner. For more articles like this, including DIY, money-saving advice, great boat projects, expert tips and ways to improve your boat’s performance, take out a magazine subscription to Britain’s best-selling boating magazine.

Subscribe, or make a gift for someone else, and you’ll always save at least 30% compared to newsstand prices.

See the latest PBO subscription deals on magazinesdirect.com