Stains in Ceiling

[Bullfrog]

Just had our first visit to our boat after all this foul weather, wind and driving rain.

 

So the Omnimax aerial on our boat's roof has been leaking water through a perished gasket around its foot.

 

I've already sealed the gap with silicon sealant, but we now have black staining along 2 seams in the light-oak faced ply that forms the cabin ceiling just below the leak.

 

Will this go away when it's had chance to dry out?

 

If not, is there any thing I can do short of replacing both panels?

 

Look forward to some helpful suggestions.

 

Thanks

 

David

 

 

 

 

[Grace and Favour]

Hmm, as it's oak-face ply - the stain won't disappear (the stain is created by a chemical reaction between the ferrous oxide disolved in the water and the oak)

 

You may well manage to substantially reduce the sight of staining with a good quality wood bleach (I'd recommend Liberon one-pack wood bleach)

 

Follow the instructions, and I'd use a fine paintbrush to paint on the bleach, following the worst staining almost as if applying scumble.

[Mike Tee]

Is it in the middle of the ceiling? Would it be possible to cover it with another piece of oak ply making it look like a panel in the ceiling in an obvious way, with a border of some kind (like a simple picture frame would look).

A frivolous answer, maybe fit a mirror in the ceiling over the stain?

[Taslim]

Oxalic acid.

[Bullfrog]

Thank you G+F and Taslim, I will probably try your suggestions first. It seems that oxalic acid is a major component of the Liberon product so that seems the way to go.

 

As for Mike T's suggestion - I had considered this. I would have to fit a full width strip of ply cos the discolouration has come out along the seams of two panels for the full width of the boat. I could then edge the patch with mahogany strip as is used at every panel joint on the boat.

 

I'm not sure about mirrors in the ceiling (very Hotel California), it's right over our guest's bed and they might get the wrong idea!

 

Thanks again

 

David

[dave-y]

Dear Bullfrog,

Further to your posted question about removing water stains back in February:

Did you ever try the Liberon Wood Bleach / oxalic acid ideas?

I have a similar problem with blue/grey water-staining on oak faced ply (covered with Liberon Liming Wax as it happens.)

I contacted Liberon, but they were rather unhelpful.

I tried anti mould (bleach?) sprays too - with no result except to spoil the surface of the varnish topcoat.

All suggestions welcomed.

Dave

[Bullfrog]

Well, I bought the stuff and took it with us on our long summer holiday down the K+A, intending to apply same in spare moments when crusing

 

Surprisingly when the weather warmed up, the dark stain in the ceiling faded away so I never actually got to use it!

 

Still got it in the drawer if it ever comes back.

 

David