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Gunwale placement

Posted by Hansen 
Gunwale placement
February 22, 2017 04:50AM
I was just browsing the photos section for about the tenth time and I noticed something new that reminded me of an old post.
From the photos of Larry Hedrick and Jeremy Christensen's decked grand canyon honky dories, it looks like they have the gunwale is attached with the gap on the outside of the boat rather than the inside... so the inwale is flush to the plywood and the outwale is held away by the spacer blocks.
If I'm seeing this correctly, it seems like somebody has already used my idea for a response to this post.
Since reading Larry's question about adding something to protect the hull from impact, I've wondered why it isn't standard practice to use the outwale as a bumper by separating it from the plywood. It seems common to mount the gunwale the opposite way (with the gap on the inside of the boat) but I'm wondering if anybody can explain why...
If Larry or Jeremy read this and could weigh in on how well it worked to have the gunwale on the outside I'd appreciate it. Larry - did you answer your own question about impact resistance? Sorry to draw so much attention to your post and your boat all at once... I promise I'm not cyber stalking ;-)

Thanks for the information.
Elliott
Re: Gunwale placement
February 22, 2017 01:44PM
These boats started out as wood frame boats with U-shaped or Trapezoid-shaped ribs inside the boat. Putting a gunwale on the inside meant notching it into the top of the rib frames, which separated it from the panel, on the inside, whether you liked it or not.

With a more stitch-and-glue arrangement, where there are no ribs, A) you don't have to space anything, you can make a solid gunwale wrapped i glass, which is super strong and B) if you do use spacers it's your choice. Put them on the outside if you wish. Or the inside. As you like it.

For any ribless boat an outwale could be aluminum square stock instead of wood. They build aluminum boats that way. Ryan Pearl makes his gunwales that way (on a molded Plascore hull). Think outside the box (outside the hull?).

On decked boats I build the deck flush to the top edge of the side panels, side-to-side, so that way there is no need for a gunwale. That way all you have is bottom sides and deck. I'm building that way now. I'll put some sort of a thin strip molding around the edge so pocket knives and fly boxes don't roll off the deck. But it won't be structural. I built my one man dayak that way.

I'm building (theoretically) a 17' footer that way now. I've had some health issues and I have not been in the shop much in almost a year. What little shop work I have done recently has been about refurbishing a nine year old lake boat.

I'll get to finishing the 17 footer eventually. And it won't have no gunwale at all.



Re: Gunwale placement
February 25, 2017 05:09PM
I'm with you on the ledge top gunwale... makes a lot of sense to me in terms of strength and storage capacity. I think the "turtle deck" looks cool too. Space for spare oars and other "lash down" items could become an issue though.
I still like the idea of a "bumper" gunwale to surround the hull. It seems like there is a breaking point where even a ledge top decked boat would suffer damage if properly driven sideways into a rock, and I like the idea of having a layer that is easy to replace take the first of that impact.

Side note: when you say "17 footer" or others refer to a traditional 17x54 (for example)... is 17' the length of the side panel or the overall length from stem to stern?

Thanks for the comments Sandy. I'm still curious why you don't see this configuration more often and if anybody knows of disadvantages...

Cheers.
Re: Gunwale placement
February 25, 2017 08:53PM
The old 15x48 was made from a 16' foot side panel, from two end to end scarfed sheets. Still 48" wide.

If you scale that up proportionately you get 17 x 54.....made from an 18' foot side panel. 54" inches wide is the same width to length ratio. 15 and 17 are overall lengths (from longer panels) while the width is an exact measurement in inches. Boat builders aren't always consistent.

I'm building a 17' footer (made from an 18' foot side panel) that is 66" inches wide under the oarlocks. I'm down on the Texas Gulf Coast now, not doing any boat building. I'm waiting for warmer weather up North :=))



Re: Gunwale placement
March 09, 2017 12:50PM
The two boat builders I know of who have experimented with wider boats are Cyrus Happy (who owns Ray's River Dories now) and me. There are undoubtedly others. Those are the two I know about.

The Honky Dory (first built in 1986) was made from a 4x16' foot side panel. But instead of a 48" inch bottom it had (has) a 56" inch bottom. That's a wide boat. That's two inches wider than most of the bigger boats made with 4x18' foot panels. At least two builders I know of have scaled the HD up so it uses 18' foot side panels instead of 16' foot panels.

56" inches wide on a 16' foot gunwale-length boat (the HD) scales up to something like 64" inches wide for a boat made with 18' foot side panels. Rows like a champ. Sits higher on the water so there is less chine deep down. So it turns fast. Climbs up waves like roofer on a ladder instead of punching into them.

I've had people tell me they want a boat that sits deeper in the water, that punches into waves instead of climbing over them. But they only know what they have. Everybody who rows a wider boat ends up smiling. I remember the first time I got my fishing guide buddy Randy Berry into an HD.

Randy and I worked as fishing guides for the Yellowstone Angler back in the early '90s. Randy had been rowing a smaller Don HIll boat I helped him restore. Randy spent that whole float spinning the boat, shaking his head and smiling.



Re: Gunwale placement
March 09, 2017 01:12PM
RE> gunwale length determined by available panel sizes.

If you scarf two 4x8 sheets of plywood together to make a longer panel you lose 2" inches or so of overall panel length. So your gunwale ends up 2" inches less than 16' long. Most builders ignore that detail. Most blueprints or plans layout from the downstream end of the panel, so the transom ends up 2" inches closer to the middle of the boat. Nobody notices. It isn't a significant difference.

Plascore is a bit different. You can buy Plascore in any length on special order but it costs more that way. Most builders buy 4x8 Plascore panels. But many use a 6" inch or 8" inch box joint when they put two panels together. That may or may not be necessary. Many builders just butt joint Plascore. If you do box joint it together the panel ends up 6 or 8 inches shorter than twice the length of one. That doesn't matter for bottom panels but it does for side panels. For side panels, if you use box joints, you have to make two splices to get 16 or 18 feet.



Re: Gunwale placement
March 09, 2017 08:57PM
Hansen Wrote:
-------------------------------------------------------
> I was just browsing the photos section for about
> the tenth time and I noticed something new that
> reminded me of an old post.
> From the photos of Larry Hedrick and Jeremy
> Christensen's decked grand canyon honky dories, it
> looks like they have the gunwale is attached with
> the gap on the outside of the boat rather than the
> inside... so the inwale is flush to the plywood
> and the outwale is held away by the spacer
> blocks.
> If I'm seeing this correctly, it seems like
> somebody has already used my idea for a response
> to
> [url=http://www.montana-riverboats.com/phorum/read
> .php?3,20053]this[/url] post.
> Since reading Larry's question about adding
> something to protect the hull from impact, I've
> wondered why it isn't standard practice to use the
> outwale as a bumper by separating it from the
> plywood. It seems common to mount the gunwale the
> opposite way (with the gap on the inside of the
> boat) but I'm wondering if anybody can explain
> why...
> If Larry or Jeremy read this and could weigh in on
> how well it worked to have the gunwale on the
> outside I'd appreciate it. Larry - did you answer
> your own question about impact resistance? Sorry
> to draw so much attention to your post and your
> boat all at once... I promise I'm not cyber
> stalking ;-)
>
> Thanks for the information.
> Elliott

All 3 dories I've built have had the spacer blocks on the inside. Outwale is flush with the outside plywood, spacer blocks inside, and inwale over the top. This gives two distinct advantages - handles, and tie downs on the inside of the boat. 90% of dories I've seen have the spacer blocks on the inside. Every boat I've seen that has them on the outside, just looks "wrong" to me.

Not sure what is going on in the above discussions (TL;DR) nor do I care, but since i was called out by the original poster, I thought I'd weigh in.

Jeremy Christensen
Re: Gunwale placement
March 10, 2017 12:48AM
Thanks Jeremy.
I must have interpreted the photos incorrectly... good to get back on topic.
Re: Gunwale placement
March 11, 2017 10:26PM
As the past owner of a boat with the gunwales built as Jeremy describes, I have to completely agree with his assessment. Great tie downs on the inside and handles that are solid when you grab them, especially in the middle of a river. When you grab the inside gunwale, you pull the gunwale into the block, pulling it against the side and the stiff outside gunwale. If that makes sense. I "think", with blocks placing the outside gunwale away from the boat, it wouldn't have as solid a feel to it. You would be holding onto something just held on by a couple screws at each block. I would like to try the former style of gunwale with an oarlock block of some design, that projects wider outside the boat, placing the oarlocks wider. Once I get building my new boat we'll see what happens, but it will have an inside spaced gunwale.
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