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New Plank Pirogue Duckin Boat.

Gamecock

Well-Known Member
Jul 17, 2012
134
1
Dave , thanks for taking time to post.Looks like a fun project with some meaning to you. It's funny how we pick up good ideas from these post. We have a similar Mennonite community close by, that built our kitchen table. They also have lots of equipment, knowledge, and willingness to help. I'd just never thought about them being a resource before. I will now!
Andy
Hey Andy, I've been dealing with these people for years both here and in Delaware. For the most part they are all good honest folks, but I have been taken by a few. Most times they provide services that aren't available anywhere else, at a reasonable rate. Dave.
 

Gamecock

Well-Known Member
Jul 17, 2012
134
1
Well, I finally got started last week. The 3/8 plywood got scarfed with my circular saw jig and that worked out pretty good. Since then I have bought a Bosch sander. I glued up the ply with West Systems 610. It comes in a caulking tube with a screw on mixing spout. Worked real nice and I probably used to much on the joint but I do have that sander now. I epoxied the knots in the cypress planks too.
 

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Gamecock

Well-Known Member
Jul 17, 2012
134
1
The next day I got the rake cut on the planks. 13ft 6in across the top 12 ft on the bottom with 2 and 1/2 in arc cut out of the bottom. The stems were cut from an old white oak 2x4 with a 30 degree angle and the end caps for the stems will be of the same. I made the center form to bend the planks and after I fastened the sides to the stems I made 2 more forms ,fore and aft, to get her shaped up nice and symetrical. I used stainless steel screws and she is now dry fitted together. Next I'll cut and fit the chines out of cypress 1x4s split in half and beveled close to size and then glue it all up. Dave.
 

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Gamecock

Well-Known Member
Jul 17, 2012
134
1
I forgot to mention that the bottom is 25 inches wide and the beam is 36 inches. Dave.
 

Gamecock

Well-Known Member
Jul 17, 2012
134
1
Thanks Guys, I really appreciate that. This forum and all you guys posting builds on here and giving support to new guys have taught me alot. It's been six years or so getting this boat started but that's just me, a day late and a dollar short. Thanks, Dave.
 

Gamecock

Well-Known Member
Jul 17, 2012
134
1
I had to change the center form so the beam is now thirty four inches wide. Seems the cypress plank I had split in two pieces for the sides developed stress cracks. Probably because the planks were now only 3/8 inches wide and the way the grain ran through them. I've glued patches on the inside of the boat using 1/4 inch plywood and filled the cracks also. This slowed things up considerable. From now on the sides will be at least 1/2 inch wide. As soon as I get the seats installed I can take the forms out and put the bottom on. I'll get some more pictures too. Dave.
 

beekeeper

Well-Known Member
Mar 4, 2009
1,489
15
Glad you are making progress. Never have built with solid cypress , but seems seedtick and Keith told me they sometimes thinned their sides from 3/4" thick to 5/8" to help them bend. 3/8" should have been even more flexible. Was the lumber completely dry before bending? Maybe the tree had a twist or other stress issues before it was milled. Good thing about working with wood is, given enough time and enough lumber any mistake can be repaired.
Looking forward to the pictures.
 

Gamecock

Well-Known Member
Jul 17, 2012
134
1
Hey Mr. Bee, the wood was good and dry, I think it must have been the way the grain ran through the boards and maybe they were too thin for the stress. The rest of my planks are 1/2 inch thick and I'll see how that works out on the next boat. Dave.
 

Kayak Jack

Well-Known Member
Aug 26, 2003
13,235
87
82
Okemos / East Lansing Michigan
I’m not experienced in bending boards or planks. I do know that getting water into wood makes it more flexible.

A long, thin slat can be lain into an eaves trough with the ends capped off, and have water poured on it. Is the wood more flexible if that water is hot/boiling water? Does higher temperature make the soaking process both quicker AND mote effective?

For larger boards/planks, what kind of a “tank” do you put them into so tney are laying in water?

When the Vikings built their longboats, how did they prepare the planks prior to bending them? Weren’t those planks at least a half inch thick?
 

Gamecock

Well-Known Member
Jul 17, 2012
134
1
I’m not experienced in bending boards or planks. I do know that getting water into wood makes it more flexible.

A long, thin slat can be lain into an eaves trough with the ends capped off, and have water poured on it. Is the wood more flexible if that water is hot/boiling water? Does higher temperature make the soaking process both quicker AND mote effective?

For larger boards/planks, what kind of a “tank” do you put them into so tney are laying in water?

When the Vikings built their longboats, how did they prepare the planks prior to bending them? Weren’t those planks at least a half inch thick?
Good questions Jack, I do know that you can steam wood to bend it. For example ox bows. A straight piece of rounded wood that is bent into a u shape using steam.
 

Kayak Jack

Well-Known Member
Aug 26, 2003
13,235
87
82
Okemos / East Lansing Michigan
It seems intuitively appealing that hot, wet wood SHOULD be more flexible. But, having a rig to submerge a large plank into can be difficult. Primitives used a lake and stones; a nice, simple solution. More modernly, maybe I’d lay a large piece of visqueen onto the shop floor, lay down the plank, fold up the visqueen around the plank to form a tub, tape it into place with a pour spout saved on top, and pour in (hot?) water.

And, probably watch water run out all over the floor. sigh
 

seedtick

Well-Known Member
Jul 22, 2006
1,143
4
Denham Springs, LA
I may have mentioned this before, if I have, just scroll on by...…..

Grow back or new growth cypress is stiffer and more brittle than old growth cypress. Not sure what you're using but grow back will be more difficult to bend. Other things to look for when bending in the sides if to be sure the outside of the boat is the outside of the tree.
inside ...)))).... outside
another thing is to try to use a board where the growth rings are more plain sawn as opposed to quarter sawn. That is growth rings should be closer to parallel to the face of the board instead of perpendicular to the face of the board

another is to bend slowly, the board will move a lot if you don't push it too fast Sometimes it has taken me several days to bend in the sides.
not sure how you're bending the sides but both sides should have nearly the same bending moment. I chock up each end of the sides and put a weight in the middle and shoot for similar bending. If one board is stiffer, then I plane a bit off until they're comparable
Splits sometime happen. That's the nature of wood not being perfect. Most of the splits I've encountered have been after the board was secured in place. Your method of sistering a board to cover the split is doable, but a thicker (therefore stiffer) section of a board will affect fairness. But if you're in a relatively straight part of the side it won't be noticeable.

You might also try fixing a split by installing a spline. Cut a kerf along the split and glue in a thin spline where the split was.

I've never tried wetting or steaming so I can't speak for either of those techniques
 

Gamecock

Well-Known Member
Jul 17, 2012
134
1
I may have mentioned this before, if I have, just scroll on by...…..

Grow back or new growth cypress is stiffer and more brittle than old growth cypress. Not sure what you're using but grow back will be more difficult to bend. Other things to look for when bending in the sides if to be sure the outside of the boat is the outside of the tree.
inside ...)))).... outside
another thing is to try to use a board where the growth rings are more plain sawn as opposed to quarter sawn. That is growth rings should be closer to parallel to the face of the board instead of perpendicular to the face of the board

another is to bend slowly, the board will move a lot if you don't push it too fast Sometimes it has taken me several days to bend in the sides.
not sure how you're bending the sides but both sides should have nearly the same bending moment. I chock up each end of the sides and put a weight in the middle and shoot for similar bending. If one board is stiffer, then I plane a bit off until they're comparable
Splits sometime happen. That's the nature of wood not being perfect. Most of the splits I've encountered have been after the board was secured in place. Your method of sistering a board to cover the split is doable, but a thicker (therefore stiffer) section of a board will affect fairness. But if you're in a relatively straight part of the side it won't be noticeable.

You might also try fixing a split by installing a spline. Cut a kerf along the split and glue in a thin spline where the split was.

I've never tried wetting or steaming so I can't speak for either of those techniques
Thanks Seedtick, I think there was less grain or maybe it ran out on the one of the board I had split in two pieces for the sides. The splits occurred on the same end of the board which was in the same end of the boat. I patched on the inside of the boat with 1/4 ply," I'll try and get pics", I pressed glue in the cracks before gluing the patches. It doesn't look good but if it paddles around in our ponds so what. I have to say that the boards bent easily when I attached them and I took my time bending. The boards were out in the shed when I started but have been inside ever since. The splits didn't show up till 4 or 5 months later. This kinda makes me think they checked from drying out. Years ago I carved duck decoys and if I used white cedar they would check after being indoors for awhile, even with sealer under the paint. This cypress I'm using is new growth and I will definetly use 1/2 inch thickness from now on. Dave.
 

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