Caulking carvel-planked hull

[Matriarch]

I'm not too thrilled with the prospect of seam filling with caulking cotton and caulk. Does anyone have experience with a "better" or more "modern" way to fill the seems between planks on a carvel-planked hull? A local guy suggested a good quality silicon caulk but that seems too easy and I've never heard of anyone else doing it. Thanks for your advice. :confused:

[Donn]

Ma, Go to the Building & Repair FAQ (http://media5.hypernet.com/ubb/ultimatebb.php?ubb=get_topic;f=1;t=008298) , and look at the first entry under "C" while you wait for answers.

What kinda boat?

[Andrew Craig-Bennett]

No better way.

But let us let you into a secret - it's rather fun to do!

[Art Read]

BEFORE you have at your boat's seams, get yourself a little tube of that fancy "silicon caulk", spread it on the edge of a piece of scrap wood and then try to ever get paint to stick to it again. Even AFTER you've sand, cleaned or scraped it all away. And don't forget that driven cotton in the seams is actually a STRUCTURAL part of your boat's fabric.

[Walcheren]

Yes it is fun to put cotton in the seams with a caulking wheel. I made my own. Then I put tape on each side of the seam and finished the seams with sikaflex. You may not want to do the taping but cleaning up sikaflex I find a pain. Above the water line one might consider using red lead putty instead of sikaflex. Works fine.

[Bob Cleek]

Your "local guy" has his head up his arse! Caulking carvel planked hulls... mmmmm... lessee... I can't think of any other kind of planked hull that you'd caulk besides a carvel planked hull. You could say you were caulking a riveted iron hull, but that's just a turn of the phrase. That involves cold chiseling the plate edges, and so on, and has nothing to do with driving cotton into the seams... but I digress.

Let me just say that I've seen more salvagable carvel planked wooden boats ruined beyond any reasonable recovery by people screwing with caulking who know nothing about it. That isn't meant to be insulting, since the only people who know anything about caulking are people who have learned how to do it right, and maybe some who learned by a process of elimination and sad experience how NOT to do it.

The first question, unless you are looking at a brand new uncaulked boat, is why does it need caulking? If it truly does, and has been caulked before, know that repair, reefing and recaulking, requires MUCH more skill than does caulking a new hull with properly fitted and beveled seams. This is where most really screw it up, ripping out perfectly good caulking because of a few (perhaps inconsequential) "weepers" and completely destroying the seams in the process, making recaulking properly impossible. The net result is a ruined boat. (BTW, nine out of ten boats that people think need "recaulking" really need REFASTENING before anybody even thinks about caulking!)

Bite the bullet and find somebody other than your "local guy" who knows his way around a caulking mallet and a bucket of irons. Pay him for his experience in cash or booze, depending upon his proclivities, and have the job done right. Your boat will thank you for it. Otherwise, if you don't know what you are doing, you might as well go fixing your wristwatch with a crowbar.

And, no Virginia... there's no "modern" way to properly caulk a carvel planked boat. This is because nobody's ever figured out a better way to do it than the tried and true.

PS: Art's comment is SO true... the hard driven caulking is a structural part of the hull. It keeps the hull from working and keeps it all rigid. You MIGHT find some goop that will keep the water out (E.g. 3M 5200 is the favorite of most fools), but it won't keep your boat together!

Don't let a good boat go bad! If you don't think anybody is going to happily pay you to do the job for them, you shouldn't be doing it yourself. Do it once, do it right, hire a licensed contractor!

[ 12-18-2003, 10:15 PM: Message edited by: Bob Cleek ]

[Wilson Fitt]

It is fun, at least until the tendonitis sets in, and not the arcane art that some would have you believe.

http://www.imagestation.com/picture/sraid93/p44c9afef0c4aa67118a42898ed1b986f/fa434e74.jpg
The cotton has been driven home in the lower seams so it's not visible in this picture.
A friend who subsequently sailed several thousand miles with us said "You mean to say that all that will be between us and a watery grave is some fake Santa Claus beard?"

http://www.imagestation.com/picture/sraid93/pa40dd6c13da95ce7a45c31e57d3c5bb2/fa434e72.jpg
Don't be put off by the caulking mallet. That's just for show. First thing I ever made on a lathe. Any wooden mallet will do.

http://www.imagestation.com/picture/sraid93/pd3c55b90032a6d8069246cf73d150192/fa434e6f.jpg
Seams filled. There's lots of conflicting advice on seam compound so pick your poison as long as it is not silicone. We used Sikaflex.

[Wilson Fitt]

My opening comment above ("not the arcane art that some would have you believe") was not intended as a slice off Bob Cleek, for whom I have great respect. His post appeared while I was lost in Imagestation wilderness. However, I am a firm believer that anyone with moderate skills and sufficient persistance can do a decent job of building a good wooden boat.

[Mr.O]

While the subject of caulking is up again let me pose a question regarding when to caulk.?? Lots of humidity now in the Northwest so planking has closed up considerably. If I caulk and fill the seams now with Sikaflex (I'm thinking) then as the humidity changes and the planks start to separate apart; will there be a lot of stress on the seam filler? Enough to cause it to separate? Should I wait until the planks are in a state of lower humidity and caulk and fill seams then? Am I creating a problem that really isn't a problem or?? I visualize seams with bulging filler or ones with deep indentations. Help me out PLEEEEZE.

[Walcheren]

I would like to know how big a boat Matriarch is working on. Caulking a 40 foot yacht is quite different from a 16 foot row boat.

[Gary Bergman]

Ditto to Art 'n Bob..I maintain a 40 footer and a 72 footer, and cotton is word. They forgot to mention the rum, tho...( and, if'n you don't do lead, try Interlux seam compound before you run for the Sikaflex)

[ 12-19-2003, 10:46 AM: Message edited by: Gary Bergman ]

[TimothyB]

Bob! You forgot to give him the link to Fab O Caulk City in England:

http://www.tradboats.com/index.html

This guy makes real caulking irons. Nothing fancy, but he has a basic kit and mallets made of the real stuff. If you are gonna be caulking anything you want to caulk with this stuff, or similiar.

--T

[Art Read]

Now that we've all beaten up on you enough about what is a WAY too common mistake, tell us about your boat. New construction, restoration or just an older sweatheart that "leaks a little"? There are people who contribute here who can answer almost any of the inevitable questions you'll have, but as you've seen, "caulking" is a pretty broad, and VERY "sensitive" subject. ;)

[Bob Cleek]

Ditto to what Wilson says above! He is right that caulking isn't rocket science. I suppose I could have been more clear, but his pictures make my point. Wilson shows a beautiful planking job there. All his seams are even and fair. I'm sure his bevels (into which the cotton is driven) are also all even. In that case, driving cotton into the seams is a joy. The amount of cotton and the depth and pressure of the set are all the same all the way.

Now, imagine those same seams after somebody has dragged a sharpened file tang or whatever across them, tearing out big slivers and gouges and so on. Then add a bunch of old cotton that just won't come out, assorted other crud and who knows what, and you have a ruined uneven seam. When recaulking, in some spots you'll have to drive more cotton and in others less, all the while trying to keep the amount of cotton and the hardness of the drive even across the whole seam. Sometimes, the seam damage is so great, like when the bevel is gouged out deeply and/or widely, that you have a hard time getting the cotton to stay in the seam no matter how hard you drive it. Then, if the back of the seam isn't good and tight, you've got the risk of hammering the cotton, iron, and all right through the seam into the inside of the boat!

I guess the point is, caulking is a lot like painting: preparation, preparation, preparation. The worst of the work in recaulking is in preparing the seam, reefing out the old cotton and leaving a good seam behind. Driving the cotton and spreading the stopping isn't that big a deal, unless you've got punk seams. BUT, like anything else, a half hour of watching somebody who knows what they're doing won't make you a master caulker, but it will keep you from botching the job.

[Matriarch]

Thank you all for the info, most of which was helpful. Please bear in mind that I asked the question because I did not already know the answer. I had always planned to recaulk (or rather, ADD some caulking) but thought it best to determine if there was something I was missing. I think we can assume that I am inquisitive, not stupid.
For those interested, my boat is a 1940 57-footer with 1-1/2" cedar planking over oak frames. (Not LAP STRAKE PLANKING, into which caulking COULD also be shoved.) The boat is very solid and although floating well with minimal bilge water/pumping two months ago, it had three weeks to dry out before it was loaded onto a truck for transport. At that time, the boat was raised and pitched slightly nose-down, which caused a LOT of water to exit the bow area FAST. Since it will not be relaunched until this summer, I thought it best to provide a little insurance before I determined that the pumps couldn't keep up with the water intake, thus creating a new marine habitat.
I do plan to assess the real needs, buy the correct tools and take the appropriate action with experienced help.

[Art Read]

Well... Now that we have a little information, the folks who REALLY know will find it easier to give you proper advice. For what it's worth, to me, your boat sounds hell for stout and should've taken the "indignities" of being hauled out and transported fairly well. (Given no other obvious structural problems) The water "flowing out" of her bows does "sound" alarming, but if she'd already dried out a bit and was oriented "bow down", it really may not be much of an issue after all. And remember, she wasn't supported on that trailer the same way she will be once she's back in the water. That alone could open up even the tightest hull! Again, experience counts here. And an understanding boatyard. As strange as it sounds, boats that leak like hell on the hard often swell up tight as drum once put back in the water. "Repairing" their caulking while the planks are shrunken and open can actually cause severe damage. A few weeks sounds pretty fast for the seams to open but moving it on the highway would speed up the drying process. It may sound like a broken record, but I think you really want someone who's spent some time around a caulking mallet to advise you. Must still be a few of them in South Carolina, no? And here's where an "understanding boatyard" comes in... You may very well want to put the boat in the water "temporarily" to help swell up the planks to the point that the caulker can do his job without risking blowing out your seams. It sounds extravagant, but the cost of a haulout, done twice, after a boat has been trucked at highway speeds and/or left on the hard is a LOT less than re-caulking needlessly. Or destructively. Got any pictures of her yet? We LIKE pictures! ;)

[ 12-20-2003, 06:29 AM: Message edited by: Art Read ]

[Ian Wright]

What Bob said to the power of ten,,,,, with an addition for the hard of stopping. Once the seams are caulked they should be stopped(filled) with linseed oil putty with a little red lead powder below the water line and white lead paste above.
There Is No Better Goop To Use And None Cheaper.
3M make nothing better neither do sikaflex. Use the real thing. It needs no improvement.

IanW

[Matriarch]

Although I probably have a couple hunderd photos of the boat, I have no clue how to add them to this post or upload them to establish a URL. I DO know how to add them to an email and will do so for anyone who requests them. Reach me at jsmthadley@msn.com

My situation here is somewhat unique in that there are no marina facilities available here on the lake. The boat will be "launched" the same way it was unloaded from the truck.......with a large crane. It will either be "seaworthy" when it's dunked or it will sink, making my homework concerning seam sealing extremely important. I'll install a "soaker hose" in the bilge and a couple on the outside to allow as much pre-launch swelling as possible.

[Bob Cleek]

Sigh... no, it won't sink when it is launched. Fill up the seams with soft soap, which will keep most all of the water out until she swells back up and will squooze out and disappear. Put a pump on her and leave her in the slings until she's proved she can hold her own. Chances are she doesn't need caulking at all. Sounds like your bilge water simply leaked out on the trailer because the forward tilt ran it up against planking ABOVE THE WATERLINE, which was dried out and open to begin with.

Now, I don't want you to get offended, BUT, it is apparent from your posts in this thread that you don't know enough about what you are doing to attempt to fix whatever problem here you might have (or not). Do yourself a favor and get somebody on board who knows what you are doing. This forum is a great place to get all sorts of advice, but you have to know what you are doing to separate the fly **** from the pepper. Half the posts in here are from well meaning folks who haven't seen a whitecap in their lives, nor done any of the tasks they pontificate about.

[Matriarch]

Bob Cleek: If you are ever offered a job with the diplomatic corps, I suggest that you don't quit your day job. I find it interesting that you, of all respondents, would use the word "pontificate." I genuflect to you, in light of your holier-than-thou wisdom, dispensed with the diplomacy of a cannon. When this "unqualified" boat owner causes your predicted irrepairable damage, I'll assume the booming voice from the clouds saying "I told you so!" to be yours. Until then, please mentor some other poor ignorant fool. My feeble brain has been overloaded with your enlightenment.

[Donn]

Ma...he's probably one of the ones on the forum who has caulked a carvel hull. One assumes he's gentler with the mallet. :D

Email me your favorite few pictures, and I'll post them for you.

donnwest@msn.com

[Donn]

Here's Matriarch's boat. A 57' Elco, ca 1940.

http://www.imagestation.com/picture/sraid93/p9d2220378e6fe9f67cf22250994b3427/fa3e54b4.jpg

http://www.imagestation.com/picture/sraid93/p8156c59620bf3b067a786a7a3deab8b5/fa3e54b5.jpg

http://www.imagestation.com/picture/sraid93/pd5201f485fb683f3443b69597e2ec9e5/fa3e54b9.jpg

http://www.imagestation.com/picture/sraid93/p26f715288d58d71d8ab71c5f70a93a73/fa3e54bc.jpg

http://www.imagestation.com/picture/sraid93/pfc06f8b58137d57324d69425e704cf78/fa3e54ba.jpg

She's gorgeous, Jan!

[ 12-21-2003, 08:07 AM: Message edited by: Donn ]

[On Vacation]

Keep talking. Some here will lead you in the direction. But what boat do you use on the local lake? Nice Boat, but where on the coast is it?

http://www.crescent-resources.com/images/residential/homes/lakekeowee/main.jpg

[Andrew Craig-Bennett]

I hope I may offer an opinion; I have not owned a boat as big as yours; but I've had my 37ft sailboat for 20 years, sometimes I've done the work myself with professionals looking on and sometimes professionals have done it with me looking on and trying to learn.

Looking at the seams in the forefoot area, I would think that the stopping should be raked out in that area and anywhere else that looks like that. The cotton underneath may well be OK - I would look carefully at it, lifting a strand in a few places. If it is white and still looks like cotton it's OK and can just be hardened down. If it has gone brown and friable then it has rotted and should be replaced. Don't rake the cotton unless you need to do so.

There is a clever way to get the stopping out without wrecking the plank edges or pulling the cotton. You need a special tool whichboils down to a rectangular bit of steel, about an inch by 3/4" x the thickness of the seams, welded onto a rod in a T shape, with a handle at the end of the T. Insert in seam and tap with hammer and the old hard stopping pops out leaving a clean seam.

Go along the seam with a caulking iron hardening the cotton down (no need to overdo it, but with 1 1/2" planking you can be fairly robust about it - you can pretty much judge by the sound).

Immediately (within a couple of hours!) after hardening down, paint the seam and cotton with primer, using a narrow brush.

Replace the stopping with new stopping as Ian Wright describes - you more or less roll this into the seam off the blade of the knife.

This is quicker and much cheaper than using 3M or Sikaflex and is what she had done to her in 1940 -she's lasted pretty well so it should be OK.

[Bob Cleek]

Matriarch, you mother... Sorry to have tangled your knickers in a knot. Sometimes I get a little testy and start typing what I thing. My long suit isn't diplomacy, the fine art of bull****ting a bull****er, as it's been described. Nice boat by the way. Let me clarify what caused me to betray an edge too raw for your taste.

Now, I don't know it all, nor even most of it. I tend not to say anything unless I feel pretty sure what I'm talking about. Something about remaining silent and being thought a fool rather than speaking and removing all doubt. What bothers me is when I see a post which by its content and language betrays that the poster really doesn't have a clue what they are talking about, nor any idea what caused the problem they are wrestling with, let alone how to fix it. This is all right. A smart guy who doesn't know asks.

Problem is, in here, in a well-intentioned rush to be helpful, people start posting all sorts of stuff, some of it helpful and correct and some of it unmitigated bull****. Pity the poor poster who's asking the question without knowing the answer. How might he guess which answer is right?

In your case, you obviously have not encountered before now even the rudiments of caulking, or you wouldn't have asked if there was some modern goop you could replace it with. (Nor would you have observed that clinker plank can be caulked.) This is fine. This is how all of us who have had some experience learned at one point or another. It is also clear that your boat is likely far to large and heavy for a do-it-yourselfer to "mess around" with. Neither can anyone here really diagnose and prescribe cures for what we cannot really identify. (Who really knows why the bilge leaked at the bow without poking around in it firsthand.)

I would just about bet that even if you were able to separate the fly**** from the pepper in here, you wouldn't have it in you to tackle recaulking a boat that size and weight. She's sit out on the hard weekend after weekend until she'd shrunk up to nothing and all her fastenings loosened and her frames cracked and eventually she'd fall apart like a barrel with a busted hoop.

A man's gotta know his limitations, as Clint sez. Given your present level of experience and the quality of your boat, she deserves to be maintained properly. This will save a lot of money in the long run. A few bucks invested in a good surveyor who knows wooden boats (not an easy find sometimes somewheres, I realize) will be able to tell you what is wrong with the boat, what needs to be done to repair it, and how much work and cost is involved. You may well decide after having a qualified surveyor advise you that she doesn't need caulking (great news), or that some small repair you can do yourself is all she needs (good news), or that this is really a job for the pros (bad news).

That's all. I just hate to see really good boats worthy and capable of restoration and many years of life ahead of them get ruined when owners have more ambition than time, skill, or money. I know, I've almost bit off more than I could chew a time or six. Blame it on the romance of wooden boats.

And don't take anything you read in here so seriously. It's about having fun.