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Adirondack
04-26-2009, 05:19 PM
I got some great advice about a year ago when I was thinking about restoring a pre-WWII wooden rowing shell which has a lot of discolored/grey wood. I bought a heat gun and followed the advice I got earlier re: how to take off the old varnish. Now that the old varnish is removed, I see lots of grey wood where the varnish was compromised over the years and water got in. I've sanded the hull, but it looks like a battleground of wood tones and grey. Most concerning is that the lapstrake edges are grey and I would have to knock down almost the entire lap edge before the color would come back.Is there a way to treat this wood or should I consider painting the outside of the hull and putting my energy into bringing back the inside of the shell to natural wood bright?Thanks

Jay Greer
04-26-2009, 07:33 PM
Since I would guess that your boat is built of red cedar, great care should be taken in dealing with the surface as it is easily damaged by too much sanding or manipulation. Treating the wood with hot oxolic acid can even out the color. However, if the results are not to your liking, the wood can be sprayed with analine dye to bring it back to its natural color. Analine dye will UV bleach over time and therefore it is advisable to cover the boat when not in use. Oil or filler stains will not absorb evenly into cedar and therefore are not a good choice.
Jay

py
04-26-2009, 10:01 PM
Patina

Adirondack
04-27-2009, 07:22 AM
Yes, I think it is red cedar. The boat was built in England, so not sure whether their choice of wood is different than here in the States, but it's lightweight and has a cedar appearence when sanded. I've never worked with oxolic acid...when you say it evens out the color, does that mean it greys the surrounding wood?Thanks

Jay Greer
04-27-2009, 08:57 AM
Oxolic acid will, in some respects, restore color. It will remove, unsightly, black iron and mold stains. Most importantly, it does even everything out. If you wish to have the original color of the wood, that is why I mentioned the analine dye.
Jay

Andrew Craig-Bennett
04-27-2009, 09:07 AM
I find oxalic acid varies in its colour effects according to the wood. It will bring the colour back to grey teak, in the most remarkable way; on mahoganies and spruce (that's the limit of my experience with it) it does not do that but as Jay says it evens things up well.

The problem with wood dye on a greyed bit of hull is that you can't readily follow the advice on the can and "do a test bit first" (!).

I've just been going through this process on mahogany and settled on a wash down with hot oxalic acid, a good rinse, dry, take down the now very rough grain lightly, a wipe with a "mahogany" dye (red) and a further wipe, when that is dry, with an "oak" dye (yellow). I think it came out all right. The "mahogany" on its own was too lurid, on a red wood.

Adirondack
04-27-2009, 09:24 AM
Thanks guys!

Lew Barrett
04-27-2009, 09:55 AM
I find oxalic acid varies in its colour effects according to the wood. It will bring the colour back to grey teak, in the most remarkable way; on mahoganies and spruce (that's the limit of my experience with it) it does not do that but as Jay says it evens things up well.

The problem with wood dye on a greyed bit of hull is that you can't readily follow the advice on the can and "do a test bit first" (!).

I've just been going through this process on mahogany and settled on a wash down with hot oxalic acid, a good rinse, dry, take down the now very rough grain lightly, a wipe with a "mahogany" dye (red) and a further wipe, when that is dry, with an "oak" dye (yellow). I think it came out all right. The "mahogany" on its own was too lurid, on a red wood.

I have had the same experiences. It seems to work best on teak, and pretty well on mahogany. I haven't used it too much on "non-boat-woods" such as cherry or walnut, but it seems less effective on cedar and fir. Just anecdotal experiences on my part. Most everything apart from teak I try it on is a crap shoot. On teak, it's a miracle worker.

Adirondack
04-27-2009, 12:08 PM
This shell is spanish cedar, so not sure how it will work...