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Darrell & Jill
08-12-2004, 12:10 PM
I inherited an old (70yrs)lapstrake cedar row boat which I want to refinish. I was thinking West system and 4 or 6 oz cloth would be the way go except for the corners of the lapstrakes? Will I have to fillet all the lapstrake corners with fairing compound before laying the cloth as the manual suggests? I want a clear finish so this would be very visible. Is there any reason why I couldn't just paint the epoxy on in multiple coats to protect and finish the wood hull without using cloth?
Thanks,
Darrell

NormMessinger
08-12-2004, 12:21 PM
Hey, if it is opinions you want let me be the first to proffer one. I think I'd not be inclined to use either glass nor epoxy on a 70 year old boat. Be true to it's generation. Epoxey does make a heck of a sealer for paint or varnish. If you have your heart set on epoxy consider something like System Three's Clear Coat then multiple coats of varnish or other top coat with good UV inhibitors. Getting glass to lay nicely over the laps will not be easy.

That'll be two cents, please.

Next.

Ian McColgin
08-12-2004, 12:32 PM
You raise some interesting problems. Expect some crossfire.

Unless you build for it from jump, it can be hard to make epoxy harmonize with such an old boat.

If she's bone dry and has been a while, chances are that the seams are nice a wide open. If rivited, you can start by tightening them up in the usual tedious two person approach. Do this and strip the wood while you contemplate the choises ahead.

Is she going to live in the water or on land? If in the water, then there's a good case for trying a totally traditional restoration as you may be able to get her tight once the planks take up a bit. I'll not address that approach here.

If you're going to dry sail her, then it is possible to stabilize the wood with epoxy but this can be tricky. I'd use WEST thickened a bit or better yet GluVit (more flexable in the cracks) to seal the laps, letting gravity help the flow from the inside first and then from the outside. If there's drippy flow-through the lap, it's easier to fair out the outside of the hull, hense the order.

After cleaning that up, I'd use CPES (now under a new name) as a primer and Cetol as a finish. Both are vapor permiable so the boat will breath and dry when up on the hard.

Glassing an old lapstrake boat can be done but it's a hideous job that mostly shortens the life of the boat and often does nothing to staunch leaks at the laps anyway.

G'luck

Cuyahoga Chuck
08-12-2004, 12:44 PM
You're right. 'Glass won't conform to the hills and vallies of a lapstarke hull. All of the gullies would have to be faired out to about a 1/2 " radius.
When you are finished the boat will barely resemble it's lapstrake beginnings.
It will also take on a lot of extra weight. Epoxy weighs about as much as water.
The amount of epoxy involved will be considerable and epoxy isn't cheap.
If this boat is a junker and you just want to get some use out of it before it goes to Valhalla do what you plan.
But if this boat has some antique value you can kiss that goodbye the minute you start applying the 'glass and goo.
Even good lapstrake boats need to be wetted so the planks swell up. If you coat everything with epoxy the wood will be protected but it may not swell enough to seal itself. Ordinary marine finishes don't seem to inhibit swelling.
Antique boats are like antique furniture. The closer they are to original the more valuable they are. The trick is to maintain value while getting some use out of them.
What you need most is to have someone who is knowledgable about lapstrake eyeball your boat and advise you on which restoration technique is for you.
Charlie

John Bell
08-12-2004, 12:51 PM
I'm with Norm.

Glass over solid timber doesn't usually work very well. It's also just about impossible to get glass to lay down over any sharp edges. Four oz. cloth might lay smoothly over a 1/4" radius, but to try it on anything tighter than that is asking for a mess.

My (controversial)opinion is that epoxy coating a surface without glass isn't worth the effort or the mess. For a sealer under varnish, let me suggest Interlux's Inter-Prime 1026 wood sealer instead of epoxy. It's a lot easier to apply and really does a nice job of getting a surface ready for varnish.

Another idea for an old traditional boat like yours -- why not just oil everything up good with some of the linseed oil and turps 'boat lotions' some of our 'old, traditional'( ;) ) members espouse?

John Bell
08-12-2004, 01:11 PM
Random thought: what exactly does "protect the wood" mean?

Does epoxy coating something really "protect" it?

Water contributes to wood's destruction only when the wood is at a certain moisture level that will support the growth of wood-eating microorganisms. Epoxy coating may help keep the wood dry enough to preserve it, but it's not impervious to moisture. Once expoxy coated wood gets wet, it may also slow down drying, thus hastening rot. Other coatings like paint allow the wood to breathe more than epoxy and proper construction and ventilation will help keep moisture levels in the safe zone. Then there's antimicrobial treatments like Cuprinol that keep the rot from even growing.

If wood is allowed to dry out too much it will check and crack, fastenings will become loose in their holes, and the boat may simply fall apart. If not that, it will leak like a sieve. Epoxy might help here, but so will paint and attention to keeping a boat in a proper environment.

Then there's the ruinous effect of the sun. Surfaces not protected from UV quickly degrade as the lignin that holds the wood fibers together is eroded away. Epoxy isn't UV stable, so it's no good in this regard. Paint and, to a lesser extent, varnish are your friends in this department.

I mean, epoxy has some good properties for boats and boatbuilding, but to automatically think that it is the best "protectant" for wood isn't justified.

End of rant. Now, back to your regularly scheduled Forum.

[ 08-12-2004, 02:14 PM: Message edited by: John Bell ]

Darrell & Jill
08-12-2004, 01:22 PM
It was in rough shape when I got it. The previous owners simply found it under their cottage. I stripped the old lead based paint off it and have sanded the wood. It has copper rivets about every 3 inches some of which are loose, which will need to be tightened. The lapstrake seams are quite gapping in places and even with swelling I'm not sure if they would tighten up. In any event I plan to dry sail her so that is not an option. I'm not interested in keeping her original or valuable but if I get a lot of use paddling my wife around the local pond, I would be happy ( and so would she ;) !). Epoxying the laps and CPES/Cetol finish sounds like a good compromise. Thanks for your suggestions.
Regards
Darrell

NormMessinger
08-12-2004, 02:20 PM
" Epoxying the laps and CPES/Cetol finish sounds like a good compromise."

Stand by. There may be other options given this new information. Epoxy gets hard. You may need something that will fill the cracks but yeald if the boards move a bit.

Darrell & Jill
08-12-2004, 03:40 PM
If the West system with fillers is too brittle to fill the gaps in the laps, what would you suggest?

CPES is proving a hard source up here in Canada, would S1 from Industrial Formulators work as well?
Regards,
Darrell

NormMessinger
08-12-2004, 05:26 PM
There was a thread or two recently in which a flexible caulking material was mentioned. I was hoping someone who participated in that discussion would chime in since I was not paying enough attention to remember what was recommended. Not 3M's 5200 nor sikaflex. Boatlife, perhaps.

Help us out here, someone.

Doug Hamilton
08-12-2004, 06:10 PM
D & J:
The line of products of Smith & Co. including the two-part sealer, CPES, and the two-part epoxy filler, Fill-it, is available from
Chuck Brown,
BCS Inc.,
861 Morton Line,
RR#1 Cavan, ON.. L0A 1C0

Jim H
08-12-2004, 06:11 PM
Originally posted by NormMessinger:
There was a thread or two recently in which a flexible caulking material was mentioned. I was hoping someone who participated in that discussion would chime in since I was not paying enough attention to remember what was recommended. Not 3M's 5200 nor sikaflex. Boatlife, perhaps.

Help us out here, someone.Wouldn't the boat have to be good and wet (taken up) before you tried to caulk her? If it's been dry such a long time wouldn't you have a lot of movement in the wood when it finally takes up again?

Ian McColgin
08-12-2004, 06:22 PM
I have successfully dribbled Liquid Lifecaulk into the lapstrake seams of an old dory made of some wood that sullenly refused to swell. But Lifecaulk is not really meant for this application and I'd have done better with Gluvit, except this was a mid winter fix and too cold to make the Gluvit set up.

The dribble problem is how to make a decent glued seam in this situation. The only product I've used that travels well is Gluvit. It's an epoxy sealer with some rubbery (not rubber I think but the quality) filler. It's viscosity enables it to travel well into deep cracks and poorly made or working seams. Lovely stuff.

Goblin's coach roof must have been canvassed originally. Chasing deck leaks I found it had been linoleumed. True! Ripped that out and did not want to do a recanvassing in the middle of the summer on a boat I lived on. After a few unsuccessful stabs, I filled the very biggest cracks with liquid life caulk and Gluvit'd the whole shebang. Worked so well I eventually just added deck paint and never did get around to the recanvass job.

It was amazingly flexable. On a hard beat, the strain of Goblin's rig wracked the boat so hard that athwartships doors could not be closed if open nor open if closed. We had a guy trapped below once till I hit on him charging the door right as I tacked!

Lifecaulk is very messy and I should not think you'd need it on lapstrake seams anyway. But get your hands on some real Gluvit. The stuff's tenacious.

If you really can't get CPES, gluvit is ok as a general sealer if you spread it as thinly as possible. I use a plastic squeege. Gluvit takes a long while to cure and will give an amine blush you won't believe. I had deck paint lift in the dory Leeward because I put the paint on two days after the Glovit - had sanded and acetone washed and thought all would be well. Give it at least a week before putting CETOL on. Gluvit goes milkey when wet and that could happen before a full cure but worry not, it will go clear again when dry and then stay that way just fine under Cetol. Gluvit is a wierd purpley brown and darkens the wood a bit but spread really thin it will not be at all offensive.

After this rave, they ought to put me on their ad budget.

Gary E
08-12-2004, 07:18 PM
Ditto Ian's recomend of Glovit. I used it on the deck, cabin top and flybridge of my sportfish. Ohh, one other thing, I put the color pigment right into it, no painting required even though they tell you to paint over it.

G

JimD
08-12-2004, 07:20 PM
Just how rough shape is she? My very limited experience repairing a very old boat with epoxy was to decide it wasn't repairable and would have to be entirely rebuilt plank by plank so I gave it back to the guy who gave it to me. I was prepared to use gobs of epoxy inside and out, and fill gaps and cracks with epoxy thickened with colour matched wood flour but in the end the wood itself was just too far gone. In any event like others say glass on lapstrake wouldn't make much sense. If you did decide to glass the planks after they were thoroughly epoxy encapsulated and glued together to make a dry, monocoque hull twer it me I'd wouldn't even try to wrap the glass over the laps, just make sure the plank edges were well sealed.

David Conard
08-12-2004, 07:57 PM
When I bought an antique cedar rowing shell, the very experienced person who sold it to me described using epoxy on old cedar as being like laying a pane of glass on a pillow. I think I would tighten up the rivets, give it a healthy dose of boiled linseed oil and turpentine inside and out, varnish the inside, use flexible caulk and a nice color of Kirby's on the outside.

Darrell & Jill
08-12-2004, 08:52 PM
Thanks all for your help, advise and benefit of experience. Knowing this kind of knowledge is so easily excessable is a big comfort.
Regards,
Darrell

Phil Young
08-12-2004, 10:19 PM
Never tried it, but I wonder if Coelan wouold be a solution. Maybe coupled with gluvit or whatever in the seams. Coelan seems to be some sort of very flexible sealing dack varnish. Do a search here.

paul oman
08-13-2004, 05:41 PM
First use a solvent thinned clear marine epoxy (or purchase such as a "pentrating epoxy - probably something with less than the 68% solvent level in CPES)

Next add a clear, non solvent flex agent to the brittle marine epoxy ($10) to get a clear coat with some flex to match that of the wood.

Finally topcoat with a 2 part clear uv blocking linear polyurethane or use varnish which will also prevent the UV yellowing of the epoxy and provide a level of warmth and depth not found in the lpu clearcoats.

cost with the lpu clearcoat would be about $250 total, including the epoxies etc. etc.

paul
progressive epoxy polymers
www.epoxyproducts.com/marine.html (http://www.epoxyproducts.com/marine.html)