Thwarts & Seat placement opinions

[BWCA66]

Looking for some opinions and I know I'll get them here! Maybe even a few related to my questions......

So my 17' Merrimack get rather unstable when someone north of 220 lbs is in the bow seat. The hull is a kevlar/carbon build and it's a symmetrical canoe.

First thwarts, there is no thwart on the bow side of the yoke. I'm thinking that adding a thwart on a 17' canoe would help, what do other canoes that length have?

Seats - the seats sit an inch or so under the gunnels ( hung from the gunnels) but 11-12" off the floor. I'm thinking of lowering them to 9" (don't kneel much anymore).

Also think I may move them to give more room for gear and pup between them. The bow seat is 25" wide at the front and 56" front the end of the canoe. The stern seat is 18" wide at the rear and 37" off the end of the canoe.

Don't want to make the seats too narrow or leg room uncomfortable. Also, use is mainly lake and rivers with no more than a class II. I'm a putzy paddler so not really concerned about speed and turning optimazation just stability and capacity. I also tend to end up with a different partner on most trips.


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[dougd]

I can only give input from rebuilding 2 MR Malecites, 16' 6" so close to the Merrimack, so not the same boat but kind of the same set up. I ended up moving the front seat back from a crazy short measurement which I don't have off hand to something like 51" front of seat to 62" back of seat. At least one could now kneel if need be instead of NOT being able to at all IMO and that is from experience. The back seat I moved forward as I use this hull for soloing with a load so can trim it out and part of that is putting my Duluth Kitchen Pack behind me which I wasn't able to do with the original seat set up. So, those measurements are 61" on the back of the seat and 70" in the front. The seat drops are only 2" so maybe playing with the length of those will help. (Just took these measurements) I'm a light weight, 140 pds soaking wet so I can't help out with that part of your equation. And like you I use mine for mostly lazy rivers and lakes.

Having the stern seat moved forward so much from the original setup has been kind of a bonus for me as I still have control with strokes but am forward enough so with some weight in the boat the bow isn't doing a wheelie! I did on one of the Malicites tried a center seat and because of my size it didn't work for crap and had to move it, too much of reach for me and couldn't keep the boat going the way I wanted. Hope this helps. BTW, these are Ed's contour seats I'm using.

dougd

 

[Chip]

I don't have advice on specific measurements, but it sounds like BWCA66 might benefit from a sliding seat set up. Put someone heavy in the bow, slide the seat back. Need more space amid ship, slide the seats toward the stems.

 

[Glenn MacGrady]

The only 17' canoe I see on the Merrimack site is the Traveler:


The fore-aft seat placements look traditional and reasonable to me.

A bow quarter thwart is usually installed a few inches behind the bow seat. It's usually only omitted if the maker expects paddlers to sit in the bow seat backwards to solo it.

A big disparity in paddler weights will always be a problem in tandem canoes regardless of who sits where. You have to compensate. Either put the heavier person in the stern and learn to paddle bow, or put gear or artificial ballast in the stern if the lighter person is back there.

I'd say the seats are definitely too high for optimal stability. Lowering them to 9" - 9.5" off the bottom, consistent with foot size extraction if you are full or part time kneeler, will increase stability greatly over seats that are 11"-12" off the floor. Seat height is the first alteration I recommend. It's easy, it's reversible, and it makes no new holes.

If lowering seat height and rebalancing people, gear and ballast don't satisfactorily solve your discomfort, only then start monkeying with seat positions. The bow seat looks as if it could be moved back a few inches, which might help somewhat with a heavy bow paddler and also as a bow-reversed solo seat. But you will probably have to buy a new seat with longer rails. In such a case, I don't think you'd have a need (or room) for a thwart behind the bow seat.

Sliding seats work in theory and sometimes in practice. But they add weight and cost and are more liable to break than fixed seats, especially when sat upon by heavy paddlers.

 

[BWCA66]

I don't have advice on specific measurements, but it sounds like BWCA66 might benefit from a sliding seat set up. Put someone heavy in the bow, slide the seat back. Need more space amid ship, slide the seats toward the stems.

I've considered that but I usually have no issues with balancing weight on a trip using placement of gear and my 70 lbs pup.

 

[Midwest Firecraft]

My 16' 9" Bell Northstar and 18' 6" Northwind both have thwarts behind the bow. The only one that doesn't is my B16 prospector, as Glenn mentioned so you can paddle solo from the bow seat backwards. That is one beautiful canoe!

 

[memaquay]

What Glenn said, lower the seats, put the heaviest person in the stern.

 

[BWCA66]

The fore-aft seat placements look traditional and reasonable to me.

A bow quarter thwart is usually installed a few inches behind the bow seat. It's usually only omitted if the maker expects paddlers to sit in the bow seat backwards to solo it.

A big disparity in paddler weights will always be a problem in tandem canoes regardless of who sits where. You have to compensate. Either put the heavier person in the stern and learn to paddle bow, or put gear or artificial ballast in the stern if the lighter person is back there.

I'd say the seats are definitely too high for optimal stability. Lowering them to 9" - 9.5" off the bottom, consistent with foot size extraction if you are full or part time kneeler, will increase stability greatly over seats that are 11"-12" off the floor. Seat height is the first alteration I recommend. It's easy, it's reversible, and it makes no new holes.

If lowering seat height and rebalancing people, gear and ballast don't satisfactorily solve your discomfort, only then start monkeying with seat positions. The bow seat looks as if it could be moved back a few inches, which might help somewhat with a heavy bow paddler and also as a bow-reversed solo seat. But you will probably have to buy a new seat with longer rails. In such a case, I don't think you'd have a need (or room) for a thwart behind the bow seat.

Yes, it's the Traveler model. I'm going to add a thwart and lower both seats and see how that works. I still may play with seat placement at some point. The leading edge of the bow seat is 7" further from the end than the leading edge of the stern seat. If I move the bow up a bit there would still be plenty of leg room and it would make the seat frame narrower reducing some of that flex.

Thanks Glenn.

 

[BWCA66]

What Glenn said, lower the seats, put the heaviest person in the stern.

I tend to take a lot of newbies to the BWCA who prefer (me too) not to be in the stern. Weight balancing usually isn't an issue even if the bow paddler out weights me.

 

[Larry650]

From the picture it looks like you have wood screws thru the gunnel holding up the seat. No washer under the screw head on top of the gunnel. That's beautiful, BUT, the only thing resisting gravity is the diameter of the No 8 screw head. I've never seen this and it looks like that arrangement would work loose after a few miles with even a average size butt in the seat pulling on a paddle.
You can probably tighten everything up with new longer No 6 or larger stainless bolts with finish washers on top of the gunnel, AND, new drops cut from the same wood and dimension as the seat.One or two inches lower on the seat has made a very noticeable improvement in stability for a couple of old boats of mine.

 

[Will Derness]

Dropping the seats will mean longer hanger dowels. Suggest you beef up the hangers to deal with seat sway issues- especially with bigger paddlers. When I’ve created wood hangers I get a rectangular oak milled piece of appropriate size and cut it to length to provide wider support at the gunwale and seat. Better yet would be a 1 piece truss connecting front and rear seat stays.

Here is a recent hanger I made trying to broaden the contact point with the gunwale.

 

[scoutergriz]

I've considered that but I usually have no issues with balancing weight on a trip using placement of gear and my 70 lbs pup.

I used to think the same until I actually got a sliding seat, it helps with a lot more than stability, it means my bow paddler can slide forward or back depending on their size to adjust legroom for comfort, and they can adjust their position to make their stroke more efficient and less tiring because they can reach the water without over extending.
It even makes portaging easier because I can use the seat position to balance the canoe perfectly.

 

[BWCA66]

Dropping the seats will mean longer hanger dowels. Suggest you beef up the hangers to deal with seat sway issues- especially with bigger paddlers. When I’ve created wood hangers I get a rectangular oak milled piece of appropriate size and cut it to length to provide wider support at the gunwale and seat. Better yet would be a 1 piece truss connecting front and rear seat stays.

Here is a recent hanger I made trying to broaden the contact point with the gunwale.

Those look great, I think I see making some of those in my near future. Thanks!

 

[BWCA66]

From the picture it looks like you have wood screws thru the gunnel holding up the seat. No washer under the screw head on top of the gunnel. That's beautiful, BUT, the only thing resisting gravity is the diameter of the No 8 screw head. I've never seen this and it looks like that arrangement would work loose after a few miles with even a average size butt in the seat pulling on a paddle.

Merrimack has been making them that way for years. I haven't had any issues with them coming loose.

 

[Will Derness]

Those look great, I think I see making some of those in my near future. Thanks!

Suggest you make hanger as wide as seat stay and even wider at gunwale. You are looking to maximize points of contact to dampen sway.

 

[BWCA66]

Suggest you make hanger as wide as seat stay and even wider at gunwale. You are looking to maximize points of contact to dampen sway.

Thanks Will! Sounds like a good project when I get back from delivering canoes to Vermont and NH.

 

[lowangle al]

I had the same problem with a big guy in my malacite. I couldn’t adjust the load to compensate and we were bow heavy the whole trip.

The next time I was bringing a big guy I brought my OT tripper and made him carry it. That worked out good for me.

 

[Mike McCrea]

Like Will Derness if I am not using a full truss drop, which is my preference, I use drops with wider contact under the inwale. I am lazy, and frugal, so I have templates for “Shallow S” curve drops in different depths.

P5260005 by Mike McCrea, on Flickr

The lazy and frugal part is that the “Shallow S” is a repeatable curve, each cut forming the side of the next (upside down) drop; no wasted wood, half as many cuts, and it is a bit more elegant than a simple \_/ wedge drop.

 

[ppine]

Remove the seats and try paddling on some milk crates. Move them around. See what works for you.
Any tandem tripping canoe should have 3 thwarts, for strength and for lash points.
Lowering stock seats can really help some canoes.

 

[goonstroke]

Like Will Derness if I am not using a full truss drop, which is my preference, I use drops with wider contact under the inwale. I am lazy, and frugal, so I have templates for “Shallow S” curve drops in different depths.

...

The lazy and frugal part is that the “Shallow S” is a repeatable curve, each cut forming the side of the next (upside down) drop; no wasted wood, half as many cuts, and it is a bit more elegant than a simple \_/ wedge drop.

Dropping the seats will mean longer hanger dowels. Suggest you beef up the hangers to deal with seat sway issues- especially with bigger paddlers. When I’ve created wood hangers I get a rectangular oak milled piece of appropriate size and cut it to length to provide wider support at the gunwale and seat. Better yet would be a 1 piece truss connecting front and rear seat stays.

Here is a recent hanger I made trying to broaden the contact point with the gunwale.

....

Those are nice drops.

While we're on the subject, does anyone have a trick for drilling a straight hole through the drops with a hand drill (i.e., no drill press around)?