Dried out hulls and sheathing a wood hull

[DownWest]

Skenn,
Resoltech make an epoxy coating sealer/primer that can be put on damp wood (RE 1010) but, you would have to ask them if it is OK with salt water.

As for sheathing, several layers of veneer (i.e. a new hull) The idea of strip planking is a no-no, as the expanding carvel planks would split the strips, Veneers would be laid on the diagonal in at least two layers so would be strong enough. The advice above is best. Let her take up.

 

[lesweeks]

My impression from talking to the Copper Coat guys at the recent LBS is that it's ideal for plastic & metal boats but not so brilliant on wood. Now they didn't actually say that, of course, but insisted that the coating must go onto clean, bare wood as the first, thinned, coat needs to penetrate the surface of the wood; i.e. all traces of previous finishes must be removed.
At that stage I lost interest having recently got my 'project' back to bare wood and then carefully primed!
How committed are you?

 

[Seanick]

Solent sunbeams

Sheathing a wooden boat in Grp or concrete is the kiss of death

Yup. So what have those very clever (and wealthy) people who run the class of Solent Sunbeams decided????

To allow the sheathing of the hulls to 'reduce maintenance'.

They seem to be ignoring the fact that it will reduce the fleet to compost in a few years.
I am relieved to hear that the Falmouth fleet will not be following suit.

One Sunbeam is currently being 'cooked' to reduce its moisture content to the Epoxy manufacturers requirement.

To win at all cost, and sod the future.

 

[Keith 66]

To my everlasting shame i was once persuaded to sheath a carvel boat in epoxy & glass, it came out initially very well. Several years down the line & before she ever went in the water the keel had split lengthways vertically, a 6" by 7" lump of old oak is never going to stay stable no matter how much epoxy you put on. She ended her days being sawed up & burnt.
If she had been a horse i would have shot her.

I am currently restoring a very lightly built carvel sailing dinghy & the epoxy sheathing route has been suggested several times, it aint going to happen on my watch.

 

[chinita]

Just for fun, and to allow me to maintain my own wooden boat, I did the one year course at the IBTC Lowestoft.

Most of the stuff in their sheds is in a similar condition to what you describe. Just about all of them will be re-caulked (the remainder being splined).

Caulking is not rocket science. It is physical, yes, and requires technique.

The College will tailor a short course for you - perhaps just a few days - to give you the knowledge and 'skills'. Why not give them a ring?

Personally, I would not consider sheathing of any variety. I like to see what is going on.

 

[DownWest]

Over the other side of the pond, they have something called 'Seam Slick' AFAIR. The excess squeeses out as the planks take up. SeaNick might like to comment on it.

 

[oldfrank]

Let's try and take this in easy stages. Sheathing an old hull is usually disastrous - and often only carried out for a few more seasons use at relatively low cost. Once water gets behind the matting it'll start to lift and the boat will rot quickly.

Splined topsides and sikaflexed bottom togther are fine ... but the sikaflex doesn't have an idefinite life expectancy.

It is possible to spline the entire hull and apply 3 (min) coats of epoxy - rollered on (without matting) and smoothed out with one of those spongey things on a stick. Paint is supposed to keep the water out and epoxy is just a very efficient paint. Use 217 hardener instead of the usual 216 - there's less of a bloom ... and when it's warmer you'll be able to get three coats on in day. You have then sealed your hull; water shouldn't penetrate and your days of moving planks should be over. You need to be very careful to ensure the entire hull is sealed (the keel is often the difficult bit - don't forget to tighten up the keel bolts). Subsequently you will have to be very careful about how much water you allow to stand in the boat - preferably none. Standing water will cause the planks to swell and give problems with the underwater splining - you can never fully stop the water running down the mast for example. This is entirely usable system - but you do have to look after it.

 

[Seanick]

Over the other side of the pond, they have something called 'Seam Slick' AFAIR. The excess squeeses out as the planks take up. SeaNick might like to comment on it.

I have used Seamslick. Its handy to have in a pot on board for a weep, but its more expensive than linseed oil putty, which is quite good enough and has worked since time began.
Once a boat is back in good ownership and in the water on time then drying out is not an issue for most boats.

 

[Seanick]

Let's try and take this in easy stages. Sheathing an old hull is usually disastrous - and often only carried out for a few more seasons use at relatively low cost. Once water gets behind the matting it'll start to lift and the boat will rot quickly.

Splined topsides and sikaflexed bottom togther are fine ... but the sikaflex doesn't have an idefinite life expectancy.

It is possible to spline the entire hull and apply 3 (min) coats of epoxy - rollered on (without matting) and smoothed out with one of those spongey things on a stick. Paint is supposed to keep the water out and epoxy is just a very efficient paint. Use 217 hardener instead of the usual 216 - there's less of a bloom ... and when it's warmer you'll be able to get three coats on in day. You have then sealed your hull; water shouldn't penetrate and your days of moving planks should be over. You need to be very careful to ensure the entire hull is sealed (the keel is often the difficult bit - don't forget to tighten up the keel bolts). Subsequently you will have to be very careful about how much water you allow to stand in the boat - preferably none. Standing water will cause the planks to swell and give problems with the underwater splining - you can never fully stop the water running down the mast for example. This is entirely usable system - but you do have to look after it.

I agree with most of the above. The issue of the Sunbeams is they are open boats, with usual paint and varnish finishes inside.

We have done some work on a 30sqM. She was epoxied in Germany in the late eighties. I have never seen a more perfect example of how to do it. The whole of the inside was coated in multiple coats of epoxy, The build up is good, about 2mm, and the finish like glass. All the steamed timbers were epoxied filleted to the planks and there are no chinks in the armour! Externally she was sheathed and faired.

I am not anti epoxy if it is done as above, but in most cases its half a job (ie external only) and is a quick fix for the short term. I liken it to putting high tech render on a house with subsidence.

Splining the topsides however is a great way to add strength and reduce maintenance. SCODS built at Burnes Shipyard over 50 years ago have enjoyed smooth topsides for years, only repainting to cover damage from mooring bouys or damage.