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Gunwale question

Posted by Samuel.tashi 
Gunwale question
November 25, 2015 02:42AM
I did a little searching but haven't found a direct answer to my question so here it is,
I'm building a honkey dory and plan to deck it. I want to build the the gunwales with the spacers and oar blocks on the inside of the the side wall. Sandy's instructions say to put the spacers on the outside. I am wondering if there is a reason not to go ahead with the spacers on the inside, and an outwale that is tight against the side wall. Either way, I am also wondering if I should expect any trouble with some sweet clear vertical grain fir making the bend at the bow. It seems pretty tight for 3/4" stock to bend in two axis, but I know its been done a thousand times.

Thanks for the advice.
Re: Gunwale question
November 25, 2015 03:22AM
I haven't used spacers in years, but when I did I found it easier to put them on the outside. I don't think there is "better way" issue here. It's more about what you want and what is easier to build.

I've built only one decked boat so far but I am now working on a second. I didn't use gunwales at all. And won't.

I built the first boat with the deck curved a bit, from end to end, so it fits down tight to the top edges of the sides. For the first boat (my little one man dayak) I bolted the deck down onto a 3/8" foam gasket for the first two seasons. Then I fiberglassed it down permanently. I'm already regretting that decision. The ability to unbolt the deck makes long term maintenance and compartment remodeling a hell of a lot easier.

I'm making a 17' foot decked dory now, made from 18' foot side panels. I'm still working out the dimensions. But that boat will definitely have no gunwales. The deck will bolt down onto a gasket. And the deck makes the boat stiff, so gunwales are not needed. That's my take. I'm not saying my way is better and I'm not saying other more traditional ways are wrong. Not at all.

I am saying the no-gunwales boat works just fine. So--somewhat like gunwales inside or out issue--it starts to look almost like a styling preference. Take your pick. I have a few beautiful 20' foot vertical grain clear fir heartwood boards in my shop. Still. That I may never use. Because I no longer build with gunwales.



Re: Gunwale question
November 25, 2015 03:41AM
There is an inside outside issue with gunwales, now that I think about it some more, that is worth considering.

If you put oarlock holes in a block mounted inside the side panel rather than outside, the center of each oarlock stem will end up almost two inches further inside the boat, which puts the finished fulcrum distance between the two pins approximately 4" inches closer together overall. Think about the width of the spacer plus the 1/4" side panel. And multiply that distance times two because the position change happens twice--once on each side of the boat.

That puts measurably less power to the oars. It might not be much but it's there and it's real. The corollary is even more interesting: the further out you put the oarlock pins the more power you have.

You can juice that leverage advantage a lot with with outrigger oarlock mounts. With oarlocks vaguely like the ones below each oarlock ends up as much as 5" inches further out, which means 10" inches more distance between the oarlock stems overall. That really makes a difference. Really puts the pedal to the metal.

I made some experimental outrigger oarlock mounts that put the oarlock pins 12" further out on each side. The power I had on the oars was amazing. That extreme arrangement did come with a price. I couldn't tip the oar handles down as far as I like, when passing log jambs. And it put the oarlock handles higher, so I had to start thinking about making the rower's seat higher. I gave up on those extreme outrigger oarlocks. But moderate ones, like the photo below, are my favorite way to go now.

The outrigger oarlocks below were an experiment. So I made the tops out of cheap AC construction plywood and didn't fiberglass them. They eventually came apart. I have a much better pair now, made with better materials. And glassed all around. I should photograph those at some point.






Re: Gunwale question
November 25, 2015 05:49PM
For what it's worth, to make an outrigger oarlock like the above isn't all that hard. You don't have to spend hours and hours carefully carving the underside so it fits onto the compound shape of a gunwale. Stretch visqueen over the gunwale, where the oarlock platform will go. Use duct tape at the edges of the visqueen to hold it on tight like a drum head.

Slobber a large amount of epoxy putty on the underside of a roughly shaped outrigger oarlock platform. Press it down onto the tight visqueen. Use clamps and an across-the-boat board to hold the outrigger platform flat and parallel to the shop floor while the glue hardens.



Re: Gunwale question
November 29, 2015 02:30AM
Sweet Sandy, and thanks for the great thoughts.
That is pretty much what I had figured. I suppose framed boats have the inwale spaced out from the side panel because the frames create a space automatically. I like the look of that. But I also agree about the need for the fulcrum to be moved out a bit. I guess the wider boat helps with that too though, at least when compared to the beam of a boat with a 48"bottom. I also like your rigger idea. could definitely be a good option.
Re: Gunwale question
December 20, 2015 05:02PM
Heres another gunwale question,
What do you guys like to finish gunwales with? Is any one using a sealer coat of epoxy, or just varnishing? I have also been thinning about sealing the gunwale bolt holes, and oarlock holes. I'd love to hear any thoughts.

Thanks in advance!
Re: Gunwale question
December 20, 2015 06:32PM
Before you bolt them on epoxy the back.

I will be using paint from now on. Any finish will be faster to apply if you do it when they are off the boat.
Re: Gunwale question
December 20, 2015 07:00PM
If you are going to deck the boat why have a gunwale at all?

Decked boats that do have a gunwale usually put the deck 6 - 8" inches below the top edge of the side panel. Then you do need a gunwale, else the top edges of the side panels would be neither stiff enough or strong enough.

But if the deck attaches flush to the top edges of the side panels the deck makes the side panels stiff. There is no need for a gunwale. I built my One Man Dayak that way. I'm planning on building my current decked 17' footer that way too.

I might glue down a non-structural something at the edges, so fly boxes don't roll off. But I definitely won't have a gunwale.
Re: Gunwale question
December 20, 2015 07:53PM
kelly Neu has a video of her going into the wall below Crystal. Wood gunwales in and out. The boat hit vary hard and broke the gunwale material and also damaged the plywood side down to the deck level. Some temporary repair mush have been needed. A deck which meets the sides with lots of glass and fiber would have been damaged too but possible not as much.

So, guess you are planning to make the deck on your boat up tot the top of side panel. It will be interesting to see what you come up with. It's will take some design for sure since the deck will need to slope down at the oars or you won't be able lift the blades high enough to clear waves.
Re: Gunwale question
December 20, 2015 10:05PM
RE> "oars down to clear waves"

I'll have oarlock towers, to raise them up.
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