Painting topsides

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dur

dur

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The top sides paint on my new acquisition is in very good order except on the seams where it is all cracked to a greater or lesser extent. At its worst very small flakes of paint are missing and the primer can be seen. A good deal of it is just a crack in the paint. The boat does not appear to leak and the survey put cracking down to "natural shrinkage and expansion"
The hull is teak on rock elm. The paint is Blakes.

What, if anything, should I do with the paintwork this winter?

This pic. is zoomed in close. The chain plate is for scale. The cracking is not any worse here than anywhere else...

seam_paint.jpg
 
I would have thought that the cracking was due to the hull 'working', but what the remedy is I confess I don't know. Hardening up the rivets [assuming riveted planking] might improve it, but that is a helluva big job. At one stage on my ol' boat, the paint was coming off in sheets, which indicated that it was time to take it back to bare wood and start again. Over time and after repeated applications, the paint film gets so thick that it develops a strength and rigidity of its own, which overcomes the adhesion to the wood. That is clearly not the case here, though.
Peter.
 
That looks pretty normal to me. Wood expands and contracts with moisture and temperature, paint is inflexible. I think that's life with a wooden boat.

I like the colour - Duck Egg Blue, I think? The same as mine.
You could try brushing on hot tar next time - that expands and sqeezes, and softens in hot weather!
 
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I would have thought that the cracking was due to the hull 'working'

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I would expect there to be more signs of movement on the inside if the planks are moving about on the timbers and I haven't noticed anything. I will have a good look next time I am on the boat but I don't think that is the problem.
 
Cracking from a hull working normally results in little saw toothed edges to the cracked paint, as the paint shears along the line of the seam. This just looks like regular expansion/contraction to me. Very difficult to avoid unless you can stabilise the moisture content of the timber. I have had most success by working epoxy filler (Microlight) into the seems when the planks were very very dry (Australia, 35% humidity, temps around 30 C). This lasted me well for around 8 years. Splining the seams is the upmarket way to have a fair hull, but no small job to do.
 
If the boat has been out of the water for some time, the moisture content will drop, and the hull change shape fractionally. If she's then painted, and returned to the water, the moisture content will come back up again, and you'll get the small movements that leave these cracks.

Surest way I've found is to leave her in the water as much as possible, and take her out to paint while it's reasonably cool. then get her back in the water as soon as possible. This keeps the hull m.c. as stable as possible. Once you build up a good layer of paint, the change in moisture content happens more slowly, and I know peple who keep their boat out of the water for several months over the winter with no cracking of the paint at all.

Personally, I've got lots of painting to do on Ruthie, and it's all happening in a maximum of 2 weeks, preferably less, in April or May, before the sun gets to hot, and the air to dry. Her hull has cracks in the paint similar to yours. I'll fair them with a random orbital, fill with primer and undercoat, then topcoat and get her back in the water. Therefore all the new paint should be applied to her when she's in exactly the same shape as she naturally is on the water.

All the above is my expereince, andd I'm sure if you get a really good seal, you can artificially keep the moisture content stable, but by keeping her on the water as much as possible, I'm hoping to let her find her own balance.
 
That looks exactly like the paint cracks I've experienced on my 1932 Hillyard. The boat's been out of the water for at least 7 years, and I am helping with a restoration. In our case, the hull was very dry as she spent those 7 years or so in a shed. I painted her early this spring, and I think that in our case, the cracking is due to our wet summer. We have had a tarp over the boat during the year or so of our ownership, but the sides are unprotected, and a summer of rain has caused the splines to swell, cracking the Blakes undercoat on top.
 
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I like the colour - Duck Egg Blue, I think?

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Thanks - a Blakes mix by the previous owner of, I think Biscay and a pale blue. Thankfully he prepared me a couple of pages of instructions on how to look after and work his boat, including the mix ratio. I like the colour too so I think it will stay for now.
 
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little saw toothed edges

[/ QUOTE ] Ah, that explains an interupted conversation I was having with Seanick in which he asked if the cracks were zig zag or straight. Thankfully they are much as the picture. The cracks generally run along one side of the seam for a while and then cross and run the otherside but not to any pattern.

I have learnt a little bit more - thanks
 
Thanks Jesse. As you and grumpydog suggest, I think the summer hasn't helped. I believe she was painted in the spring, when we actually had the summer, and then, of course, it has rained since.
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fill with primer and undercoat, then topcoat

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So a light sand over the the whole of the topsides and pick off any loose paint on the seams. Then prime and build up undercoat on the seam, sand back then top coat? One topcat or two?
 
When I started work on my Hillyard's topsides each seam was in a similar state, only worse with lumps missing along the length.
One side was worse than the other... likely because the dark green hull had suffered from exposure to the sun.
I abandoned the idea of burning off the old paint and starting again after boatyard advice and went to with a random orbital sander using 80 grit. Where the seams were very dry I raked out to the cotton and filled with a putty and white lead mix. Then primer undercoat x 2, faired off then another undercoat and two coats of Blakes Pearl White.
Since then I have repainted twice, once while the boat was still in the water. The seam splitting has much reduced but there will still be work to be done.
Its a case of steadily keeping on top of thing, I don't expect it to be completely cured.
 
Its always safer to keep to one paint system, they are designed to work as a system. I've used dulux weathershield on boats and regard it as a very good quality paint particularly good on wood IMHO.
 
johnstones primer

I think you mean to say Undercoat......... thats what should be used to fill scratches ect!!

I personally use any Primer and then use Dulux Weathershield undercoat and topcoat. Some people swear by these products on wood boats (I'm one of them) others have had bad experience with the products. It is, I feel all down to the preparation.

My hull is carval and I get asked many times if she is GRP......... GRP indeed Huh!

Tom
 
I wouldn't have a problem changing to Weathershield (used successfully at home for some years) apart from a: the limited colour range and b: as a newcomer to a woodie which is also already in nice order, I think I should be careful about too many changes early on. If that makes any sense!
 
Fair enough, but don't be put off by limited colour range, I have had great fun mixing the different colours to get the colour I want......just be sure to keep a note of the proportions of each colour.
 
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