Sharpie Questions

[Forbsie]

1. The bottom of my boat is painted with black stuff that looks like tar but the builder says he used black rubber paint from Alsfords. When I scrape it off it comes off in a dust and leaves a black lustre on the wood. It has preserved the wood very well. Any idea what this could be?

2. The planks that make up the bottom have daylight showing between them. Will they take up when put in the river, should I fill the gaps with red lead putty, fill them with whatever the answer to 1. above is or is there another answer?

3. A patch of about 3" x 1/2" at the transom end of the starboard hull is a bit damp. This is on a 17' x 2' plank of Honduran Mahogany. I don't think that I need worry too much about it yet but is there any treatment that I can apply to dry it and protect it.

I hope that the sages of Classic Boat Forum can help me on these and I apologise for not using the correct terminology.

 

[snowleopard]

Your planks will probably take up if the hull is currently very dry. It's impossible to say for sure because of all the variables. If you decide to fill the gaps, be sure to use a non-setting compound. If you caulk, the whole hull could be damaged as the planks swell and have no room to expand.

If the wet bit is soft, you have wet rot. Let it dry out thoroughly and treat with Git-Rot which is a resin and anti-fungal combined.

 

[DanTribe]

If that was Alsford the timber & builders merchants, the black rubber paint may well have been Synthaprufe.
It is a chlorinated rubber bitumen compound used as a damp proofing in buildings.
I used it on my boat for some years on the recommendation of the boat yard. Very effective for sealing leaks and not bad as an antifouling, as one year I couldn't afford antifouling and had less growth than usual.
It was a 'orrible job removing it eventually though.
Not sure if it's still available under that name. Try a builders merchant.
Dan

 

[Peterduck]

If you can't find Git-Rot, try International's Everdure. It is essentally the same thing; a very thin epoxy resin with a fungicide. Make sure that the area is REALLY DRY before applying it, as any moisture left in there won't be able to get out and you'll make things worse.
Peter.

 

[Forbsie]

I bought a tin of Aquaprufe. I wonder if that's the same thing. I'll check with them tomorrow.

 

[Captain Coochie]

I bet hes black jacked it , bitumen based rubber sealant , great stuff . Dont think they make it as good now .