Strip plank maintainance/repair

[Jack Heinlen]

I've been contemplating this boat.

http://media5.hypernet.com/ubb/ultimatebb.php?ubb=get_topic;f=6;t=002967

I finally got ahold of the owner last night, and what he told me had me lamenting a bit.

Here's the deal, the boat is strip planked with Eastern White Cedar, resourcinal glued and edge nailed with bronze. So far so good. The rub. She's been on the hard much(almost half) of the last decade. Seams have opened up. The current owner attempted a repair by filling the open seams with unthickened West epoxy. Several more have subsequently opened up.

My question, not being terribly familiar with the construction technique except in theory is, wouldn't putting something hard in those seams when the boat was dry cause further separation down the seam when the boat goes back in the water? My thought would have been to leave them alone. Another question, if you can speculate long distance off a description: what could be done to fix this?

[Jack Heinlen]

I'll have to go see it before I can answer your questions Mike. It didn't make much sense to me either. He said he'd used tape to hold the epoxy in. He's getting a little on in years, and insisted when asked that is was unthickened epoxy.

This brings up a point of theory. A boat like this needs to be in the water, as much as possible. When you think about it, edge glued cedar on her forms a solid piece of wood, perhaps fourteen feet wide amidships. Wood moves, roughly, 3/16 to 5/16 over a foot. It's got framing running against the movement of the wood. When dried out something's gotta give, and it won't be the WO framing or the ply bulkheads. Filling the seams with anything hard isn't the answer, getting the boat back in the water is. I fear this guy made a major boo boo.

There's a reason this boat is still on the market. A part of it is these issues. I'll go have a look see next week, and try to get a better sense.

Further comments are always welcome.

[ 08-20-2004, 09:09 PM: Message edited by: Jack Heinlen ]

[Scott Rosen]

Forumite Todd Schliemann has a strip planked auxilliary, and I remember him writing a lot about his hull maintenance issues, including open seams. You could look up some old posts, get his email and get in touch with him. He keeps his boat at Coecles Harbor Marina in New York, which has a good crew that's experienced with wooden boats. I'm pretty sure he's got some useful information for you.

[RonW]

I revived this thread from the 2nd. page, I think there may be more information about construction technique then appears on the surface of the thread.

It has been a long standing debate on traditional strip planking, not to use hard glues between the strips or at least on the larger strips.The argument being that if you use a hard glue like epoxy or recorsinol, that the whole side can contract and exspand from keel to sheer as one piece and then literally split and possibly force planks off the transom due to pressure. Could this be the problem with this boat? What would the condition of the boat be if there was nothing between the strips, as originally was done in traditional strip planking.Would some of the strips only have slight hairline cracks, but no splits, and by adding moisture or putting it back into the water, you may have just a little seepage for a day or two and then all is well.
Could this be proof of not using hard glues with strip planking?
The boat is 32 feet long, 37 years old, cedar strips on oak frames and I would guess that the strips are approximately 1& 1/8 inch thick. Could there be too great of a contraction and exspansion rate between the oak frames and cedar planking, that may not present a problem with carvel, but strip planks hard glued may create a problem.

Any opinions on this? And remeber this is not a 19 footer with 5/8in. thick planking.

[TimothyB]

According to other sources than I, strips will only expand much if you use hardwood for it, which is why cedar is specified for most strippers, regardless of nailing or gluing.

Basicaly, you need to use a stable softwood. Cedar, good pine, even Mahagony strips.

Redmond has some info about it on his web page concerning Elver:

http://www.sredmond.com/strip_plank.htm

[RonW]

Timothy B. you are correct and I agree with you.
Steve Redmond's discussion on strip planking is the most and best on this subject that I have seen so far.It has been in my favorites list for a long time. I have researched this subject for several years, and hopefully this fall or spring will start on a 23 ft. lobsterboat in traditional strip planking.In doing the search thing again, I just came across a post I missed, just posted in july, and it states that richard pulsifer has been building his hamptons out of traditional strip planking, with beveled not cove and bead strips, nailed with bronze ringshanks and using of all things 3m5200 between the strips. He also doesn't use any glass in or out.I found that to be interesting and really right on target with my research. Besides resorcinol and epoxy being used between the strips, I have also read red lead paint, white lead paste, nothing, and now 3m5200.I find it interesting that chapelle staes that the method dates to the very early 1900's but did not gain favor among builders due to the high cost of nails. That problem has been solved.I also just read that one of john gardner's last 2 books has quite a discussion on strip planking and I think he advocates nothing between the strips.

[TimothyB]

I have JGs book and yes, he does advocate nothing at all between the strips. Of course, he is talking about specifically doing the strips as bevelled by hand, carefully fitted so that there are no gaps between strips, much the same way you would do carvel (i.e., no gaps when final fitted dry)

Of course, there are those of us who (a) are not skilled enough to do this or (b) dont want to spend the time doing it hence the use of something like 3M 5200 as a sealant between strips. If they loose fit, the 5200 will ensure a tight bond while they take up.

I like (i believe it was paladin) the advice that one should use a circular saw to make the fits next to perfect. Aside from the garboard plank, which I suppose would have to be carefully fitted by hand, he suggested you setup a circular saw to ride the outer edge of the plank being fitted, so that the saw blade is set to take 1/2 the width of its cut from plank #1 and 1/2 from #2. Then you clamp down a slightly over sized strip and run the saw through the line where the two strips meet, thus making a very flat join.

In those cases where the curve was extreme, you could run it through a few times to get flat, full width joins.

There is wood wastage, but if you are using softwood it shouldn't be too pricey to waste 10% or so on this.

This way you would have what I bet could be pretty close to perfectly fitted joins in a fraction of the time. So maybe you could use gardner's advice after all.

[ 08-28-2004, 09:46 AM: Message edited by: TimothyB ]

[HarryH]

About 30 years ago I purchased a nice little 17' working skiff built in Nova Scotia, the hull built on the lines of traditional lobster boats. (In fact, it came with an old working head for hauling pots.) It was strip planked pine over steam bent oak. The planks were wider than thick, perhaps 1-1/2" and 3/4" respectively. When out of the water for the winter, you could slip a credit card through the planks, and those were the smaller sized gaps. She would go down to within a foot of freeboard when I put it in come spring. When I bailed her out several days later, she shipped NOT A DROP for the rest of the season, unless I did not go out in her often. Then the planks above the water line would tend to open up a bit, and water would spray in while planing! Then it would tighten up again.

God I loved that boat. Sweet lines, strong and heavy. True to the economics of the area and times (I guess), along with the use of native pine planks, it was edge fastened with 6d galvy common nails, and clinch nailed at the ribs with cut nails. No glue.

Because of the comings and goings of the planks, particularly at the turn of the bilge, it was tough keeping paint on it all season. And an occasional-bleed through due to an errant nail needed attention. But overall it was a handsome and uncommon craft, and drew comments.

Anyway, it sold me on strip building. I'm starting a 23' Downeast design, which will utilize 13/16" sq strips, edge nailed and glued. But this boat will utilize more upscale materials: wana, resorcinol, bronze.

My .02

Good Luck..

Harry

[RonW]

Very good conversation Tim & Harry. I have always question the use of strips that are not square, but twice and more the width versus the thickness.It seems to me that square strips are more stable, and I will add that I think after ripping them, even from kiln dried lumber that you should give them at least a month or so to stabalize before applying them.It looks to me like these wider then thick strips are a lot more like a minaturized carvel planking then a strip planked, but without the rope to take up slack for contraction. Harry gives a valid example of the contraction on his boat, here again the strips are twice as wide as they are thick.Suppose 50 years ago you told the nova scotia builders of harry's boat that they needed to use resorcinol between the planks.Could they have given you a funny look and responded that it will split itself to pieces when it drys and contracts. I am not opposed to useing a glue, but more opposed to using wider rather then square stock. Go back to the original post on the 32 ft. sailboat, I would bet the strips are somewhere between 1 & 1&1/4 inch thick, and if they are 2 or 2&1/2inch wide with resorcinol glue, Then it set for years and dried out and contracted, is the hard glue holding the planks tight why it is splitting? Through exspansion and contraction something has to give somewhere.If this is the case, then it is a construction technique fault.There are becoming more variations on the strip planking method, and I am not sold that all the variations are solid and stable.Some of these may not fail for 20 or 30 years later, it just takes time for them to blow themselves apart.
Glueing up or laminating small pieces into a large piece becomes a stable piece,but glueing large pieces together can create too much pressure on the glue joint or wood if the wood is weaker then the glue line, and with hard glues the wood is generally weaker then the glue line.

A couple more comments or opinions on strip planking-traditional. I think that square strips not only are economical to obtain, but it gives you the option of applying the strips whichever way you want to obtain proper grain orientation. You could roll the strip 90degrees for grain orientation. I am under the opinion that if the grain was 90 degrees to the frames, that when you nail them, the nail is going through multiple layers of grain, not only does this reduce any chance of splitting, but also aids in a reduction in exspansion and contraction. In nailing I think that the traditional hot dipped galvanized trim nails would be better then bronze ring shanks with heads.Remeber that the nail is totally encased in the strip. But the big advantage could be that you could drive the trim nails at a slight angle left or right, causing the nail to act more like a drfit pin then a nail.The ring shanks with a head would have to be driven at 90 degrees for the head to lay flat, and then you loose the drift pin effect. Plus you have the flat head to contend with. The trim nail could be set with a nail set, this could give you the option of using a small hand plane to the top edge of the strip to create the bevel necessary to get the 2 strips to fit very tightly to each other, and being pulled even tighter by the drift pin effect of the trim nail.I would be inclined to think on smaller boats, particularly trailer boats that a more flexible glue might be in order then a hard glue like resorcinol or epoxy. And as far as a 40 or 50 footer with 1&1/2 inch or greater thick strips that properly fitted strips would be better off with nothing between the strips.Of course I would use bronze screws to fasten the strips to the frames.

My comments are out of the hope of obtaining any and all information on the subject. So feel free to add more info concerning a technique that very little is written on or maybe totally understood.

Harry what plans do you have for your strip planked down eastern? I have glen-l's eagle the rounded chime version in a small lobsterboat.They also have the double eagle a hard chime, sawed frame plywood version. But I thought I would take the easy route, all just for those soft riding, pretty, round chime hulls.Oh well. Plan on useing southern yellow pine for frames and strips, little white oak for capping and so forth.

[HarryH]

My boat was designed by a fellow named Frederick W. Bates of Damariscotta, ME in 1965 and redrawn (mostly for powerplant revisions, I think) in 1973. My set, purchased in '75 is number 139 (I am building it almost 30 years later; don't ask).

I understand Mr. Bates (now deceased) sold hundreds of sets worldwide. It caught my eye while thumbing through "Sportfishing" magazine in the early 70's, where as a mini-feature, the article touted its lines and design heritage. Mr. Bates, a marine designer, built the first one for himself. Although the plans are well detailed, it is assumed the builder can handle lofting and is at the very least a skilled woodworker with some boatbuilding experience. It is not for the first time builder, but Bates did keep the non-professional in mind by simplifying construction without sacrificing sea-worthiness, function or beauty. Laminated stem, use of plywood where it makes sense, strip planking, etc. help meet his desire sucessfully, I think.

I finished the lofting, have my keel stock and planking on order, and am gluing up the 4x5 stem over a jig I recently finished.

I am happy. I feel like this is the boat for me, and am thrilled to building it. Hope some of this is helpful.

_H

[Tonyr]

Ronw, I see that you have the Glen-L Eagle. Do you mean the plans, or have you actually built the boat? I am at the epoxy-and-fibreglass-ing stage on the planked hull of a stretched (24 ft) version, at this time. I used white cedar for the strips, and PL Premium as the glue.

So far so good, but it is quite a project, more than I anticipated.

Tony.