View Full Version : carvel seams again

Bill Griffin
04-26-2010, 08:48 PM
I know I'm probably getting ahead of myself here, but... I started wooding my hull this weekend. Carvel planked, cedar on oak. The frames all need to be replaced, so I'll be removing all the bungs to fasten the new frames. Apologies for no pictures, I'll make a note to take the camera with me next work day.
As the old paint disappears, I see that the seam compound is mostly dried out and cracking. I picked a bit out, and see that the seams are caulked with cotton. So my question with no pictures is, is there a method to tell whether the old caulking is ok, so I don't have to pull it all and recaulk too?
The boat is S&S weekender, 30' on deck, built in 1935. It appears to have been refastened some time ago, using (mostly) the original holes in the planking, so I think, hope, I might not have to replace much of the planking, if any.
I've searched for threads on seams, but couldn't find anything on the condition of old caulking, other than if it's ok to leave it.

peter radclyffe
04-26-2010, 10:55 PM
you can pull some out at random, if its powdery or falls apart its shot, if you can harden it up, it may be o k, if it goes thru to the inside look at the condition of it, if its no good, usually its almost impossible to harden up
after hardening you can prime the seams with red lead or marine wood primer

04-27-2010, 06:16 AM
I would reef out the seams if I were reframing or refastening. This will allow the planks to pull tight against the new frames. When I refastened, I used a hook made from a hacksaw blade, a razor knifie, and a paint scaper (small triangular) to clean the seams.

Todd D
04-27-2010, 07:57 AM
I agree with John - you will need to reef the seams out to properly set the planks onto new frames.

Peter Malcolm Jardine
04-27-2010, 10:32 AM
Seam compound that is dry and crumbly is shot.

Bill Griffin
04-27-2010, 04:52 PM
Thanks guys. I didn't get to the boat today for pics. I can tell the compound needs to go. It sounds like I will also plan on removing the cotton caulking and recaulk also?

04-28-2010, 06:33 AM
Yes. You will find that some of the caulking comes out with the compound. Some can be pulled out in strings. Some has to be reefed out.

05-04-2010, 03:10 AM
Some old books of mine mention a mixture of linseed oil, red lead and putty for seaming compound. Not sure of the proportions through. Any ideas on this or is it not as good as newer products. I have a seepage through the hull and I am going to have to address this when 'Huia' comes out in a few months, cheers Don

wizbang 13
05-04-2010, 03:16 AM
reefing the seams will be a small part of what you are about to undertake

Lew Barrett
05-04-2010, 10:08 AM
If you have red (or white) lead and want to mix it in with putty and some oil, that's just fine. I'd probably use white lead myself if I had it depending on what
color the topsides are going to be. You want a nice trowelable paste, sort of firm.
I suspect the pol is added for ease of tooling in. Otherwise you can use a commercial seam compound such as Interlux's, and add white lead paste to it as well. Or just use the commercial stuff. I like the idea of mixing in the lead paste and you could do that to make the jib easy; mix some white lead putty and commercial seam compound. You'd have some good stuff.

05-07-2010, 10:38 PM
Thanks for the replies, very helpful. So if i am doing the seams below the water line how long before I can apply primer and anti foul after applying the putty and lead mix? Cheers