I gave my old 16’ Royalex tandem to my son, who probably isn’t going to use it. I may take it back and replace the broken middle thwart. I would use it as a solo, not a tandem, so would sit on the bow seat facing the stern. Problem is the additional thwart that is just behind the bow seat, which precludes sitting backward. Any reason I couldn’t move it elsewhere? What about adding thwarts in general-is it
foolish to toy with design?
Thwarts
how important the thwarts are depends on how ridged the gunnels are. My Royalex Explorer with aluminum reinforced vinyl gunnels came with two seats and a portage thwart. No thwart behind the bow seat. I recently broke the portage thwart. I only miss it when I’m lifting the boat. I’m sure that a pin in strong current would make me miss that thwart but for now it doesn’t seem to be a problem.
If you are using the boat in fast water I’d say move the thwart to the other side of the seat. If you are not then try paddling without it. If the boat is flexing more than you like then replace the thwart.
I have moved them on several
canoes without any problems, but the most I have moved them is about a foot.
Cheers,
jackL
Horse’s mouth
I was just in the same situation. I made a thwart to place on the other side of the seat keeping the original to swap when used tandem. I used SS wing nuts to make the swap fast and easy.
I wrote to Bell to ask them about the wisdom of moving it and here is part of their reply:
“We place a thwart behind the bow seat to make a stiffer, better handling canoe; it’s a Bell Trademark. Your wiggling bow ballast (he’s referring to my pup) probably won’t notice much difference in the overall performance of the canoe with out the bow thwart.
The other option is a third seat or kneeling thwart.”
play with it
Since your tandem is also probabbly pretty wide at the center for solo paddling you could also install a shorter thwart and pull the gunwales in a few inches.
I completely removed a thwart on my wifes solo canoe when I replaced all the wood on it. What does a 13’ canoe need 2 thrarts and a seat for? I would have left out the front thwart too, but its nice to attach things to.
tandem -> solo
– Last Updated: Apr-06-06 10:29 AM EST –
When I converted my MRExplorer from tandem to solo, I removed the center thwart and replaced it with two shorter thwarts displaced about 2 feet fore and aft of center. The 4 foot separation distance more or less matched that of my (factory solo) Courier and looked about the same as pictures of some other MR solo boats. I've never noticed any flexing or torquing, but I haven't pinned it of wrapped it either.
I use a clamp-on carry yoke.
Since then, I've horsed around with a variety of center seat arrangements - a Voyageur slant seat/removable carry yoke lashup, a kneeling thwart, nothing at all, and finally a Northwater adjustable saddle with thigh straps. I like the last best.
The arrangement has a lot of plusses. With the thigh straps removed, I have a huge open work space for poling, it's easy to lash gear in, and it's open enough to bivouac under (try to sleep under a canoe with a center thwart).
hth,
rj
THANK YOU ALL…
…FOR THE GOOD IDEAS. I SHALL PROCEED. HOPE I DON’T WIND UP WITH A WOODEN DECK STEM TO STERN.
have fun
You’ll end up liking your boat more once you’ve messed with it a bit.
Not that it’ll necessarily perform any differently, but it’s just good boat-owner bonding if you don’t mind fiddling with tools.
P.
I just asked…
Sawyer about adding a thwart near my foot braces to hang a thwart bag for easier access while underway. Sawyer replied:Adding a thwart will affect the handling characteristics of the canoe probably in such a way that you wouldn’t like the way it handles after the thwart is added. If you like the way it paddles now, it would definately change with the front thwart added. I like the way it handles,so I am letting it alone.
Happy Paddling billinpa
Was the Sawyer guy
recently seen on Lake Lelanaw?
Just kidding… I gotta agree with Mike on this one. If you don’t spread or reduce when you add the additional thwart, your just gonna stiffen it more. No hull characteristics affected other than that…
Sort of …
but the genius of the open canoe (like the viking boats before it, maybe after it) is the structural balance - supple enough to absorb vibration and shock, rigid enough for efficient propulsion and control responsiveness.
If you’ve ever tried to paddle a canoe with failed
{rotted out) gunnels or broken thwarts, you know what a pig it is. A rebuild or repair transforms it from a '58 Buick to a Miata.
I think that most factory canoes are delivered with a decent balance for their advertised purpose.
1.) Should you simply remove a center thwart? No.
2.) Should you simply add thwarts? Sure, if you want a more responsive boat (and you’re willing to accept maybe a little more risk of damage in a crash or a wrap).
3.) Should you jam in a longer center thwart? Sure. A lot of polers do this routinely to increase the width of the boatprint on the water and increase the rocker making the boat turn more easily.
4.) Should you tuck in a shorter center thwart? Sure. It’ll narrow the boatprint on the water and reduce the rocker. Theoretically anyway, it’ll make for a better laker.
5.) Should you put in wider decks or longer bow or stern handles? Go ahead. It might make for a dryer boat without doing too much damage to other parts of the performance.
6.) Should you replace the center thwart with two different length thwarts fore and aft? Sure, if you wonder what the deal is with asymmetrical hulls. Do it and report back here.
7.) Should you put in adjustable thwarts so you can accomodate different service requirements? Sure. Do it and report back here.
–
Hth,
rj
speaking of wooden decks…
I was thinking about optimizing a tandem canoe for dog transport by removing the center thwart and replacing it with a long plywood “doughnut” : outside edges attached to the gunwales and extending to the forward and aft thwarts, inside cut out leaving a 4" web all around. I thought it might give the dog more room to move fore and aft, while keeping her more centered side-to-side. Any opinions?
dognut
– Last Updated: Apr-06-06 2:15 PM EST –
I'd say go ahead and try it. It figures to make the hull MUCH stiffer in torsion.
(This means make damned certain the hull is straight when you screw down the panel.)
--
rj
Thanks for calling my attention, Mike
I’ve been sort of out of the loop lately. I have given a lot of thought to this changing the rocker question. First I had to figure out a way to actually measure the rocker. I picked up some information from John Winters, designer of the Swift Osprey which is my favorite ride. He measures from a point 1 foot back from the 4-inch water line mark at the stem. On the Dagger Sojourn I just did, that figures out to 2-feet back from the point of the deck plate. Next, how to get a straight line for reference bench mark. Turn the canoe over on saw horses and use a string? Nah, too flimsy. Place the canoe upright on a concrete floor? Yeah, sort of, but very awkward to peer under there and squinch up my bifocals to actually read the tape. Then, Eureka! I found a little $9 bullet laser level at Lowe’s. Just turn the canoe over on sawhorses, measure to exact center, place the little bullet level on the center spot, and move the canoe back and forth to get the bubble level. Then shoot the laser fore and aft and measure up from the hull to the laser beam.
The first canoe I messed with thwarts was the Mad River Freedom Solo. It is a wet ride in big wave trains because of the narrow bow, so I popped in a new forward thwart adding 3-inches. Any change in the rocker is negligible, and the canoe does ride the waves better now, IMHO.
Then I traded for a Dagger Sojourn solo which has a reputation for being hard to turn. The advertised specs are zero rocker aft and 1/2-inch forward. I put the laser level on there and sure enough, the stern was negative 1/4 inch, and the bow was zero rocker. That, combined with a very aggressive “skeg-like” shape to the stems makes the canoe very hard to turn. I left the deck plates and carry thwarts in place and added 3-inches to the fore and aft thwarts, and 3-1/4 inch to the seat. This brought the rocker to 1/4-inch stern and 1/2 inch bow. The turning resistance is greatly reduced, yet the straight ahead tracking is still really good.
So, if I added 3-inches to change the rocker by 1/2-inch, then my assumption is a 6 to 1 ratio. But, like Mike says, a study pool of two boats is pretty weak. I have a Supernova in the works now that I’ve ordered from the factory and asked them to bring in the gunnels 3-inches to make the paddle station narrower. I’ll let you know how that has changed the rocker when the boat gets here in a week or so.
Cheers,
AndyLee