strip advice

[outrigger man]

After years of reading im finally a member and have the ability to converse with some of you old salts, Thank you. Im building a outrigger canoe and want to use as many recycled materiels as possible, Im planning on building the main hull out of 3/4 square red cedar ( i traded a truck load of clear for a roof repair) and dont want to glass it. Question one is what glue would you recommened between strips ( im planning on nailing them together). Question two is where the strips die into the stem what would be the best way to fasten them. Question three is are there any enviromently friendly products that i could coat the hull inside and out with this type of construction. Thanks again although construction is my trade this is my first boat and am open to any and all comments.

[gibetheridge]

Can you show the plans, or pictures of an existing hull?

[Rich Jones]

3/4" square strips, that's going to be a pretty beefy canoe. That sort of construction is usually used on bigger, beamy craft such as rowing and sailing boats. I'll be interested in the responses, though, as I might want to build a 14' sailboat with the same construction. I like the idea of strip building, but don't want the fiberglass. Most canoes are built of one-quarter inch strips and glassed inside and out.

As for your questions: Either epoxy or resinol (the water added to powder glue) Epoxy is very strong and has gap filling properties but is hard to sand. Resinol is likewise strong, waterproof and might be easier to sand(I've no experience with it), but is not gap filling and requires tight fits. Since there will be no epoxy and fibeglass to seal the wood, I'd seek advice on fasteners. Any kind of steel nails (which are only there to hold the strips together until the glue drys)might start to rust and bleed through your paint. Also with strip-plank construcion, you'll need some ribs, but not nearly as many as carvel. That's another advantage to fiberglassing; it adds rib-like strength to the boat. As for the stem, add some countersunk and bunged screws to add to the strenght of the glue holding the planks. Most boats of this type are finished with an oil-based paint. As long as you're not dumping the left over paint on the ground, that should be eco-friendly enough!
I'm also a carpenter and found that boatbuilding is a welcome relief from the straight lines of everyday carpentry. Plus, it's a real mind-bender and stimulates your brain. Keep us posted.

[mcdenny]

Welcome to the forum. Lots of experienced folks here who are happy to help. What design are you building? Where do you intend to sail?

In general, PL Premium would be a good choice for gluing the strips together. It comes is a caulking gun tube so is easy to apply to the strip edges. You can get a tube for $3 at the local big box store to try.

Be careful taking an existing design for a stripper meant to have fiberglass skins and converting it to your thicker strips with no glass. Wood generally and cedar specifically has very little cross grain strength. Before fiberglass/epoxy steam bent ribs provided cross grain strength and that is what the fiberglass in contemporary construction is for. I imagine it is possible that closely spaced, stout, long nails might provide this strength but you should make sure your method is sound before you build a boat. Maybe others with experience with this method will chime in.

[WI-Tom]

3/4" square strips, that's going to be a pretty beefy canoe.

I agree. The 18' ketch I'm building now (http://www.dhkurylko-yachtdesign.com/build.htm) uses 1" x 1/2" strips, and it's designed the way you mention: edge nailed and glued, 7 laminated frames, and glass sheathing optional (abrasion resistance) but not necessary for strength.

Of course, using 3/4" x 3/4" strips means you'll be able to really go to town on the hull with an angle grinder or belt sander for fairing (fun fun!), without having to add as much expensive fairing compound (which, since it's not weightless, would make for a heavier boat). You could shave 1/4" off the hull thickness and still be fine. (But would you WANT to shave that much off?)

I think PL Premium or even Titebond would be fine. I didn't bevel my strips, so I used epoxy to fill the gaps. PL Premium would work for that, too--and be a heck of a lot easier to work with! (cheaper, too). But for some deep-seated faulty emotional reason I felt better about using epoxy.

Tom

[WI-Tom]

Question two is where the strips die into the stem what would be the best way to fasten them.

I used stainless screws. Left some in, pulled some out after the glue dried.

Tom

[Y Bar Ranch]

This is one of my bookmarked sites...

http://www.selway-fisher.com/Stripplank.htm

[Frank R]

Please follow this advice:
Use a plan that is devised for this type of construction. You will have too many skills to learn and mistakes to correct while constructing the boat to have to worry about adjusting a plan to suit your building needs.

My opinion is that strip planking will result in a hull that is way too heavy for an outrigger canoe.

You can rip your cedar into 1/4 inch strips and glass the interior and exterior. The glass goes transparent and leaves the beautiful wood to show. Epoxy is not some evil eco-unfriendly material.

[wizbang 13]

So,what is this boat, a canoe or a sailing catamarang of some type? bona fide design?size and use?
Strip planking, red cedar ,3/4 "squares,epoxy, is an excellent way to build a boat, jus depends on what boat.

[Cuyahoga Chuck]

Your building plans seem kind of vague and your intent to be eco-friendly may get in the way of practical boatbuilding. Your first crack at boatbuilding will be hard enough without a lot of self-imposed add-ons.
The general thrust of strip planking is there has to be something substancial to lock the strips together. In the old days it was a lot of steamed ribs clinch-nailed to the strips. Today it's epoxy and fiberglass on each side. Or glass on the outside and some kind of frames on the inside. The idea of just gluing strips of lumber together doesn't seem practical.
Here's an articlel on doing strip building the old fashioned way. Edge-nailed strips and steamed ribs. It will give you an idea of what kind of engineering is required to produce a substantial stripper hull.
http://www.svensons.com/boat/?p=Utility/DollyVarden

[Bob Cleek]

Buy all of John Gardner's excellent books on building small craft (available from the WB Store). Read them until you have a complete understanding of the building techniques he describes. Pick a design from his books that is simple and easy to build. Follow the instructions. Don't get ahead of yourself, Grasshopper. The only "environmentally friendly" boatbuilding techniques are the traditional methods, devised before mankind invented a lot of nasty chemicals. Boats held together with petrochemical resins and solvents, goops and goos, aren't "environmentally friendly" and aren't anything near inexpensive, compared to tried and true traditional construction. The only catch with traditional construction methods is that you have to learn them. Those skills come out of experience, good advice, and well-written books, not out of a tube or a can.

[WI-Tom]

Boats held together with petrochemical resins and solvents, goops and goos, aren't "environmentally friendly" and aren't anything near inexpensive, compared to tried and true traditional construction.

Hmm... I spent less than $400 on my goopy, gooey, petrochemical resin-laden sailboat. This summer I spent 20 days sailing the North Channel in it. Not to mention various other shorter trips.

And haven't I been hearing about a soybean-based epoxy that's less toxic? (Maybe on the Duckworks forum?) Of course, industrial agriculture is involved, so no doubt Mr. Cleek will point out that it still doesn't qualify as "environmentally friendly." I'm sure all of the tools he recommends--hand tools, of course--for traditional builds are unsullied by the petrochemical industry in any way. They're not made by machines, or shipped anywhere. Customers don't drive cars to stores to purchase them.|;)


The only catch with traditional construction methods is that you have to learn them. Those skills come out of experience, good advice, and well-written books, not out of a tube or a can.

Yep, no skill involved with modern glues. In fact, my whole BOAT came out of a can! It's great! Just pop the top off and there it is, a boat!! My sails--a lateen, a spritsail, and now a balance lug--they came out of a tube!!! Along with all my spars!!!!! (That was a looong tube, of course.)

There's about a gazillion ways to build a boat. Most of 'em even float. No dogma necessary. Have fun.

Tom

[Gary Dierking]

Outrigger canoe hulls generally have a near constant midsection with most of the curvature (and bending of your planks) occurring near the ends. 3/4" thick planks would be very difficult to bend that much unless steamed. How long is your hull?

[bennieboat]

"There's about a gazillion ways to build a boat.
Most of 'em even float"

yes, mine is one of them

eh, when you don't glass the strips
then don't glue them ?

just nail the strips onto eachother every few inches
and screw the strips to the stem

and coat the hull with traditional varnish inside
and above the water outside;
paint it under water
environmental contribution: no antifouling

that is the way my sailboat was built almost 60 years ago
( like the other few thousand of the same class )

it is left in the water during 'summer' seasons
and kept on the hard in winter, outside
for repairs and varnish

the wood strips will shrink in winter,
leaving in water after launch, for a week
then the wood swells, watertight again

it needed new decks and major repairs after 40 years
(then i bought it)

it is still sailing

i know, this is a dumb answer
i shouldn't give an anecdotal answer to a general question

what i want to say: when done right, and with some luck, the simplest constructions will last and last, when not neglected

but without knowledge
glue with thick epoxy and coat with thin epoxy
then paint it
very forgiving
( that is the way my boat lasted another 20 years )

Ben

[outrigger man]

Heres an atempt at some of your questions, the design is based off off gary dierking Ulua, I was thinking the extra width on the strips would replace the strength of the glass its 20 ft long 19 inches wide and 22 or so deep, Im planning on two bulkheads for and aft sealed with flotation also a few partial bulkheads for the seats. its going to be on the hard between usess due to convience. I thought about pl premium but was concerned about fairing due to its seemingly poor sandable qualities. im not too concerned about a little extra weight but want to insure strength a much as possible. thanks again and Im all ears. fastener advice is welcome also should the strip grain be horizontal or verticle for best strenth, what about alternating them? Gary your the man ive read the pages out of your book I was thinking of building a lamenated stem with a dado in it to "catch" the ends and give them some holding strenth. Surely you have built a strip without glass what was your experience in a nutshell?

[outrigger man]

the plans call for 6 oz glass inside and out on 1/4 inch thick strips and i was thinking the extra wood might compensate for the lack of glass I like the idea of soybean based epoxy, has anyone had experience or know a supplier?

[andrewe]

Apart from the structural reasons for glassing, cedar is fairly soft, so the glass gives it some scrape/ding protection. Friend had a strip-planked, galv nailed and glued (urea formaldahyde aka cascomite) 24ft sloop. Built in the 60s, still good, but not from cedar.
A

[wizbang 13]

Sounds like you seek to convert a boat designed for strip built ( ala canoe) into strip planked. bad idea
Drift from the design to make a "greener" boat?
Save a gallon of gas if you think it will save the world, more gas for me.

[Canoez]

the plans call for 6 oz glass inside and out on 1/4 inch thick strips and i was thinking the extra wood might compensate for the lack of glass I like the idea of soybean based epoxy, has anyone had experience or know a supplier?

You should use the glass as specified by the designer. I'd stick with epoxy if I were you. The two layers of glass are there for both strength and to protect the relatively soft core material from rot and other mechanical damage. The advantage of using these materials is that if properly constructed, you will have a light and durable hull that will take less fuel to transport and will last for a long time, reducing the need to build a second boat in future because the boat you propose didn't have great longevity. Otherwise, Mr. Cleek's suggestion of picking a boat designed for more traditional construction if you choose not to use epoxy is the better option.

As a rule, boatbuilding is not generally the world's most eco-friendly activity. All construction methods have some consequence. You can choose traditional construction using things like white and red lead in the construction along with solvent based coatings and wood - including some that may have travelled from far across the globe. You can also choose some more modern methods that use high-tech adhesives and coatings. If you're bent on being totally 'green' I suggest you look to the types of boats that were built by "first peoples" in the area where the style of boat that you are interested in was traditionally built and studiously copy their methods and materials.

[Dan St Gean]

You should use the glass as specified by the designer. I'd stick with epoxy if I were you. The two layers of glass are there for both strength and to protect the relatively soft core material from rot and other mechanical damage. The advantage of using these materials is that if properly constructed, you will have a light and durable hull that will take less fuel to transport and will last for a long time, reducing the need to build a second boat in future because the boat you propose didn't have great longevity. Otherwise, Mr. Cleek's suggestion of picking a boat designed for more traditional construction if you choose not to use epoxy is the better option.

As a rule, boatbuilding is not generally the world's most eco-friendly activity. All construction methods have some consequence. You can choose traditional construction using things like white and red lead in the construction along with solvent based coatings and wood - including some that may have travelled from far across the globe. You can also choose some more modern methods that use high-tech adhesives and coatings. If you're bent on being totally 'green' I suggest you look to the types of boats that were built by "first peoples" in the area where the style of boat that you are interested in was traditionally built and studiously copy their methods and materials.

I've built Gary's Ulua in cedar, glass, and epoxy. Great boat, and I still feel fine about the environmental consequences. If you are using wood--that wood had to be harvested, transported, milled, etc. Even first peoples tended to use lots of resources for craft--whole logs carefully chosen for a single boat, debarking birch trees for canoes, etc. Let's not get too hung up on the eco nature of boats here as mining lead, pouring it, and then gloating about how one sails and doesn't use a drop of gas in it's use?

I'd say build Gary's boat as designed, and enjoy a super paddling and sailing experience.

Dan

[Canoez]

I'd say build Gary's boat as designed, and enjoy a super paddling and sailing experience.


Absolutely.

[Todd Bradshaw]

I have yet to strip any round-bottomed hull where a goodly number of the strips didn't need to bend and twist, often to a rather great extent. If you try to strip an Ulua with 3/4" strips, I'm pretty sure that you will soon run into areas where your strips just won't make the curves and twists that they need to make. If they even can be forced into that shape and you don't have skins reinforcing them, they'll probably split wide open the first time the weather changes. If you're dead set on 3/4" strips and no fiberglass skins, I'd start looking at some of Gary's hard-chined, flat-bottomed designs made for plywood construction. They still may not be a sure thing when it comes to bending those big strips, but your chances of being able to do it would increase substantially.

[alkorn]

I imagine it is possible that closely spaced, stout, long nails might provide this strength but you should make sure your method is sound before you build a boat. Maybe others with experience with this method will chime in.

Three or four years ago I did a test to compare cross-grain strength of epoxy-glued WRC strips with no edge fastening, edge fastened with trunnels, and edge-fastened with ringshank nails. None of the test samples had glass on them. I posted the results to the forum:
http://forum.woodenboat.com/showthread.php?76103-Strip-Plank-Edge-Fastening-Test&highlight

The sample was too small for the results to be conclusive, but it appeared that:
- the trunnels did not help the cross-grain strength at all
- the nails did not increase the load at which the sample began to fail, but made it fail more gradually as the nails pulled out.

This was a pure cross-grain failure test, and the fasteners did not make a dramatic difference. My interpretation of the results is that in a real hull with some frames, where both along- and cross-grain strength contribute, fasteners would not do much to increase the strength of epoxy-glued strips.

That being said, what concerns me about your idea is the overall expansion and contraction of the hull. If you repeatedly wet and dry the hull will the strips split? Will they pull off the frames?

[Cogeniac]

Eco Friendly.. hah...

So, go find a deadfall tree and cut it up using a hand saw.. Oops! removing the deadfall tree will eliminate a habitat for the critters and bugs that are meant to return it to the earth.. hewing the timbers will require tools that consumed energy to fabricate, and you, yourself will consume energy that will have to be replaced by food.. food that probably is not carbon footprint free, nor is it petrochemical free...

Then again, when your no glassed boat made with strips too thick curve as needed AND to stay attached without adhesives, starts to sink, I suppose you will avoid calling for help since that will involve boats with motors...

Seriously, you may be taking the eco-friendly thing a bit far (soy epoxy? somehow, that doesn't sound right...) Have you considered some other hobby like hiking?

[wizbang 13]

Hello Alkorn, I looked back on your strip plank test./thread.
First, I wonder where all those former members went, I have only been here 14 months?
As I mentioned earlier, strip built is a different animal than strip planked.
Strip built needs the sheathing inside and out, and does not need the internal /vertical fastenings. It is for canoes and light small craft.
Strip planked, is for larger vessels. It does not need sheathing. Some say it does not need the vertical nails,which I disagree. As far as I am concerned ,eliminating the fastenings in a strip planked boat is like eliminating there re-bar in cement work.
2 different things.

[outrigger man]

As for Cogeniac s' assumption that im a hippie, I would like to clarify, that this is based on his northern Ca. association. Im anything but a tree hugger. I hate glass work and have had experience due to surfing and surfboard repair. I love woodworking and also the idea of building with strips being that I come across good wood for free or close to it often ( always in smaller pieces). I appreciate the helpful comments from the rest of you. As the 3/4 wont bend as quickly i have contemplated streching out the bow and stern to accomidate this.

[Cogeniac]

Yea, I think all of the hippies retired here in Sonoma county ;-)

Actually I was poking a little fun at your goal of true eco friendliness. Sorry if you took it wrongly.. The problem being that it seems no matter what you do, anything other than living like the first people is bound to be eco-unfriendly.

I understand your aversion to glass. It's icky messy stuff to work with, but for some applications it is far superior. For a canoe, you might just look to canvas and some sort of paint. a 3/4 plank canoe will be mighty heavy! Indians used Birchbark, so maybe there is some more up to dat approach like that you can use.

If you are dead set on using 3/14 plank, then I'd suggest something like a catboat. Big round tubby craft that can be trailered...Whatever you decide, be sensible so that you don't end up with a boat that is too heavy to use conveniently, or too weak to survive any sort of on-water "adventure".

Cheers.
S

[outrigger man]

no worries, I was thinking that the weight between the plan specs of 1/4 inch with 6 oz glass on both sides, to straight 3/4 wouldnt be that much different and 3/4 glued and nailed with bulkheads has got to be plenty strong enough. Although none of this is based on engineering or experience thus im here trying to gather some advice. My eco friendliness is driven by cost ( i have guns drive a truck chew and was born in tx. :)

[Cogeniac]

"i have guns drive a truck chew and was born in tx. ..."

LOL, hence the aversion to Norcal Hippies!! I think it's something in the Texas aquifer.

The weight thing might be about right (I didn't do the math to compare), but the benefit of glass is that it ties the strips together along multiple axes of motion (some more than others). I am sure you can do it, it may leak a little and such. Probably the biggest issue is the one raised by another post. Specifically, getting the thick strips todo what you want at the ends where they need to take compound curves. You may need to steam them to get them to fit without a) a lot of effort, and b) a lot of strain on whatever is fastening them in place...which may lead to faster failure or plank cracking, etc...

[JimConlin]

"i have guns drive a truck chew and was born in tx. ..."

LOL, hence the aversion to Norcal Hippies!! I think it's something in the Texas aquifer.

The weight thing might be about right (I didn't do the math to compare), but the benefit of glass is that it ties the strips together along multiple axes of motion (some more than others). I am sure you can do it, it may leak a little and such. Probably the biggest issue is the one raised by another post. Specifically, getting the thick strips todo what you want at the ends where they need to take compound curves. You may need to steam them to get them to fit without a) a lot of effort, and b) a lot of strain on whatever is fastening them in place...which may lead to faster failure or plank cracking, etc...

I did do the math . 1/4" cedar strip composite will be half the weight of 3/4" unsupported strip planking and the strip planking will be desperately weak in the transverse dircetion. I'm not from either CA or TX.

[outrigger man]

Thanks for all the advice, i appreciate it alot due to my lack of experience. I tested the bend towards the bow and stern and it was rather easy. As for the transverse strenth i will need to look up what this is before further comment:) . I decided to do my own test on weight difference, even though the weight on paper pencils out at half i find that this is hard to belive. Perhaps its just my glassing?