Zig Zag ribs - ever been done?

[bredlo]

Here's an odd question.

Does anyone know if a canoe has ever been built with the rib ends touching each other... making them appear as a single, 17 foot long zig zag? Without knowing much about wood, engineering or boatbuilding, it seems to me you might get a similar strength, while using at least a third fewer ribs - making it significantly lighter, though somewhat harder to construct (bending the ribs in two directions, fewer places to nail the planking, etc.)

To take the design a step further in complexity, you could criss-cross ribs like shoelaces, rabbetting the fronts and backs along the keel line for an intricate lattice pattern.

Maybe it wouldn't be as structurally sound, but I wonder if it'd be any worse than, say, a board and batten canoe. Here's a quick photoshop sketch of what I'm envisioning...

 

[pklonowski]

Zig Zag ribs

I'm no expert, but I would think that the spaces between the ribs are unsupported, and thus would be prone to the planks bending inwards more when pressed into a rock, log, or other obstruction. This would concentrate lot of strain on the planking at the spots where it finally crosses the ribs, making the planking more susceptible to breakage at these points.

Again, I'm no expert... maybe a boat designed for light duty only could get away with it?

 

[Michael Grace]

Maybe this is what the builder was going for when constructing the canoe that Greg posted about in the "Open Forum":

http://forums.wcha.org/showthread.php?t=4541

Seriously, though- why? Other that weight savings, there seems to be little value, and I doubt the weight savings would be significant. It's fun to speculate about such things, but for the added difficulty of this method vs. little weight savings, I doubt it would ever be done (or have been done) in any serious manner.

Michael

 

[bredlo]

Michael,

That thread is exactly what prompted me to wonder if it'd been done intentionally. I agree, the extra work would make it unlikely that somebody would try a stunt like this more than once.... still, I ought to mock up a lattice version as - in my head, anyway - it's just lovely.

Good point Paul on the larger unsupported areas - that could definitely pose problems.

 

[NedL]

Interesting idea, though I don't think it would be particularly easy to get them to lay flat against the planking.