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Forum topic by indplswoodworking posted 05-04-2014 09:33 PM 3332 views 4 times favorited 135 replies Add to Favorites Watch
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indplswoodworking

281 posts in 1012 days


05-04-2014 09:33 PM

Topic tags/keywords: question

I am interested in designing and building a wooden kayak! After reviewing several plans I think it is doable. Has anyone every built or finished one and has information to share?

These are the free plans I am considering following. The are very detailed and give dimensions , parts list , and step by step instructions.

http://www.guillemot-kayaks.com/guillemot/blog/nick/ganymede_offsets_free_plans_build_ganymede_kayak

The best part is they are free and downloadable.

Thanks Gary from Indianapolis

-- https://www.facebook.com/MccloudsCreativeConcepts


135 replies so far

View Mark Shymanski's profile

Mark Shymanski

5115 posts in 2431 days


#1 posted 05-04-2014 09:41 PM

Check out the podcast “Hooked on Wooden Boats”. It is a pretty good source of information about the world of wooden boats. Some of those Guillemot kayaks are beautiful!

-- "Checking for square? What madness is this! The cabinet is square because I will it to be so!" Jeremy Greiner LJ Topic#20953 2011 Feb 2

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shipwright

5215 posts in 1516 days


#2 posted 05-04-2014 11:29 PM

Looks pretty doable. I’ve never built a kayak but I have built a few boats. If you have any specific questions I can help you with, feel free to PM me.

-- Paul M ..............If God wanted us to have fiberglass boats he would have given us fiberglass trees. http://prmdesigns.com/

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AandCstyle

1419 posts in 976 days


#3 posted 05-05-2014 01:21 AM

You might consider this one from FWW:

http://www.finewoodworking.com/membership/fwnpdf/011095067.pdf

If your not a member it was in the July/August 1992 issue. The author claimed you could complete it in 2 weeks. FWIW

-- Art

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runswithscissors

1146 posts in 744 days


#4 posted 05-05-2014 07:21 AM

I have built several stitch and glue kayaks from Pygmy kits—Goldeneyes and Cohos. They will sell you plans as well as kits. The stitch and glue process is fast, simple, and builds a very strong hull. There are several designers of S & G kayaks, but I am convinced Pygmy’s system is superior.

CLC (Chesapeake Light Craft) sells plans for several models, and there are others, whose names don’t come to me right now. I don’t have access to the FWW article without a trip to the library. Guillemot usually specializes in cedar strip construction, which is laborious but makes a beautiful craft.

I am concerned that that design being offered looks like a flat bottom—as near as I can tell from the photo and the dimensioned plans. The flat bottom can be very satisfactory in row boats and sailboats, but it can be dangerous in a kayak. That’s because they have little to no secondary stability. With a normal V bottom or round bottom kayak, as the boat heels, you encounter resistance to further leaning (not a huge amount of resistance; you can, of course, capsize). A narrow flat bottom boat can have quite a bit of primary stability (i.e. when sitting upright), but when heeled suddenly reaches a point of no return and goes over. Don’t compare it to a dory, which also has a narrow flat bottom, because the dory has sharply flared topsides which provide the secondary stability. If anybody wishes to prove me wrong here, have at it.

If you build this boat, be sure to practice some wet exits first before you take it out onto big water.

If you are interested, I can go into more detail about why I like Pygmy’s stitch and glue system over all others. I can also help you through any difficult spots you might encounter. Feel free to ask.

-- I admit to being an adrenaline junky; fortunately, I'm very easily frightened

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indplswoodworking

281 posts in 1012 days


#5 posted 05-05-2014 11:20 AM

Thanks for all the informative and encouraging feedback. Honestly, I was unaware of so many people are experienced in boat building. I would expect because they are busy applying epoxy to the boats or in a waterway enjoying them. HAHA I am going to review all the information provided at this point.

Honestly , this first boat is to test and hone my skills.I have 20 years of woodworking experience and have owned bass boats in the past so I have a GENERAL familiarization with the processes and am familiar with learning as I go. If I enjoy the process I will purchase plans for more of a streamline plywood kayak in the future but intent to only take this to a lazy lake or reservoir in central Indiana a few times a month. I will not be launching it in any raging rapids. Just to do a little bird watching. If it turns out well I may sell it and use the proceeds to buy that streamlined version mentioned before.

-- https://www.facebook.com/MccloudsCreativeConcepts

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indplswoodworking

281 posts in 1012 days


#6 posted 05-05-2014 11:24 AM

First questions : Luan or the fancy marine grade plywood?

I will be using cloth and epoxy on the hull that should completely strengthen it and waterproof the vestal. I understand Luan has voids and the marine plywood is far superior. I just don’t want to over engineer the kayak. And most importantly the Luan is way cheaper and I am familiar with staining and finishing the veneer.

Let me know what you think! I am literally days away from taking the plunge and buying the goods. Thanks!!

-- https://www.facebook.com/MccloudsCreativeConcepts

View Mark Shymanski's profile

Mark Shymanski

5115 posts in 2431 days


#7 posted 05-05-2014 01:17 PM

Voids can be a pain in the neck, not while building, but when using your boat. You can put a huge amount of effort into a boat only for a rock to find that void with only one thin ply holding the water out. I built my first (only, so far) boat from 3/8 construction grade plywood. I’ve coated ghe entire exterior in epoxy and am counting on the over design thickness to hold the water out should I hit that mythical rock.

-- "Checking for square? What madness is this! The cabinet is square because I will it to be so!" Jeremy Greiner LJ Topic#20953 2011 Feb 2

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jmartel

2557 posts in 869 days


#8 posted 05-05-2014 02:55 PM

You should use marine plywood. There are 3 basic grades of marine plywood though. Aquatek, Hydrotek, and Okume. They vary in quality with Aquatek being the worst, and Okume being the best and lightest. They also vary in price accordingly. 4mm stuff I believe is somewhere around $50-60 for Aquatek, $70ish for Hydrotek, and $90-100 for Okume. Aquatech tends to splinter more than the other 2, and Hydrotek being in the middle.

Runwithscissors, this is indeed a flat bottom kayak. It does have flared sides, though. Flares about 4” at amidships. Flat bottoms do not necessarily mean less secondary stability. It depends on the flare, and the round bottom boat you are comparing it to. In this case, it should be plenty. The hard chine adds additional strength as well, which reduces the amount of framing needed and allows for a lighter boat.

It’s not a particularly pretty boat, but it should perform ok. Personally, I would buy plans for a different boat. I don’t like the hull shape. Plus, I prefer the strip decks. Look for a hybrid boat where you have the Stitch and glue hull and strip decking. Below the waterline it is easy to build/fix. Above the waterline is pretty.

I design boats for a living, though they are quite a bit larger and usually steel.

-- End grain is like a belly button. Yes, I know you have one. No, I don't want to see it.

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indplswoodworking

281 posts in 1012 days


#9 posted 05-05-2014 07:45 PM

I am sold on the marine plywood!

My next step is making the final decision on the plans then off to the lumber yard!

I will be posting more info very soon and thanks for all the great feedback!!

-- https://www.facebook.com/MccloudsCreativeConcepts

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runswithscissors

1146 posts in 744 days


#10 posted 05-05-2014 08:03 PM

I agree that the chine makes the hull into a sort of torsion box (it will be very strong), but I’m not convinced it will reduce the amount of framing. In fact, the only framing in the Pygmy boats (multi-chine Coho and Goldeneye, or V bottom Arctic Tern), consists of the bulkheads, and even they may be left out. No other transverse framing at all, nor any fore and aft timbers (keel, chines, etc.). I suspect the dead flat bottom (not quite flat, as the sides, when pulled in to form the 4” flare, will create a small amount of fore-and-aft rocker) will easily “oilcan.” This is why many lightly built plywood dinghies have an internal and sometimes external keel as well.

Of all the plywoods, I would vote for okume. 4 mm (about 3/16”) is a good compromise between weight and strength. There are other more expensive and prettier plywoods, but they tend to be heavier. Okume isn’t noted for its decay resistance, but a boat sheathed in glass and epoxy (DON’T use polyester resin, even though it’s cheaper) shouldn’t be a problem. I would certainly store my kayak out of the weather. UV is as hard on them as anything.

I should clarify the term “round bottom.” About the only truly round bottom kayaks are racers, and they are as squirrely as you could imagine. The typical kayak (unless V bottom) should be called round bilged, as the actual bottom may be nearly flat or slightly V-ed.

If the discussion should reach the point of how to join panels to gain length, I have more opinions to vent, but I’ll save those for later.

-- I admit to being an adrenaline junky; fortunately, I'm very easily frightened

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richardwootton

1408 posts in 674 days


#11 posted 05-05-2014 08:31 PM

Gary, I’ve been wanting to build a stitch and glue kayak for some time now. I’m an avid recreational kayaker, but I’m no crazy whitewater guy, class three is about as high as I go with my skills and boat. Good tip on practicing the wet exits, they’re not hard at all, and I’m sure if you google it there will be several videos on YouTube. Good luck and post pictures for us!

-- Richard, Hot Springs, Ar -- Galoot In Training

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jmartel

2557 posts in 869 days


#12 posted 05-05-2014 10:02 PM

Typically, chines do add quite a bit of strength and reduce the amount of framing needed. The bottom flat panel is a pretty wide area without any buckling support, however. That is the limiting factor here. A chine will not negate the need for a keel, but it will reduce need for stiffeners and bulkheads. That’s what I was referring to. In a kayak, it’s pretty negligible, as the small and typically round shape don’t require much bracing anyway. It’s more of a benefit in larger boats.

-- End grain is like a belly button. Yes, I know you have one. No, I don't want to see it.

View Planeman40's profile

Planeman40

502 posts in 1479 days


#13 posted 05-05-2014 10:28 PM

“Voids can be a pain in the neck, not while building, but when using your boat. “

When using thin plywood like 1/4”, voids can be found and marked by placing a strong light with a reflector around it very close to the plywood underneath. Darken the room and move the light around. Voids will be seen as bright spots. Mark out with a pencil on the plywood surface and work around them. Also, inexpensive exterior grade plywood can be used if you are looking for a savings. You are going to glass over the surfaces anyway. “Marine grade” only means surface grade wood is used throughout and the glue is waterproof. Exterior grade ply uses the same glue but uses cheaper inner plys with occasional voids.

However a note: I did all of this back in the 1970s while building a homebuilt plane. In the following years things may have changed. I recommend you call Weyerhaeuser or Georgia Pacific and confirm.

Planeman

-- Always remember: It is a mathematical certainty that half the people in this country are below average in intelligence!

View Mark Shymanski's profile

Mark Shymanski

5115 posts in 2431 days


#14 posted 05-05-2014 10:40 PM

I’m going to gave to store the ‘strong light’ trick for future builds, thanks Planeman.

-- "Checking for square? What madness is this! The cabinet is square because I will it to be so!" Jeremy Greiner LJ Topic#20953 2011 Feb 2

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runswithscissors

1146 posts in 744 days


#15 posted 05-06-2014 12:44 AM

I would avoid any plywood from the big box stores. Their’s will be fir, yellow pine, or, as you mentioned, luan. Marine grades are costlier, but worth it. And I think 1/4” is too heavy, and not needed for strength in a kayak. Though you might make a case for it—for the bottom only—in a flat bottom boat. People have used 1/8” (3 mm), but that will make a somewhat fragile boat, though very light. And don’t fall into the temptation to “add a little structural support here, and bit of beefing up there,” as that kind of thing leads to added, and unnecessary weight. A properly built plywood kayak, 15 to 17 feet long, should weigh no more than 35 to 45 lbs; a bit more if you have bulkheads and hatches. If you don’t put in bulkheads and hatches, plan on float bags to make your boat unsinkable.

I hope I don’t sound discouraging. I know you can do this. Around here (Pacific NW), we see people buy what I call “pond boats,” try paddling them, discover they don’t track worth a darn, are agonizingly slow, and are virtually helpless in any kind of wind, and then wonder what all the fuss was about. So they give it up, not realizing how a superior design can bring a load of fun and all-around satisfaction. You can use a good kayak for birdwatching, fishing, gunkholing, and camp-cruising. Once you’ve gained the necessary skills, you can take them onto big water—even the open ocean and through surf.

-- I admit to being an adrenaline junky; fortunately, I'm very easily frightened

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