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Re: Strip: How necessary are stems?
By:ScottBaxter
Date: 12/9/2011, 5:11 pm
In Response To: Re: Strip: How necessary are stems? *PIC* (Bryan Hansel)

The biggest problem I have with this entire thread is that I look at my gut and all other comments about weight seem irrelevant. Then I look at my camera gear and I think 15+20=almost the weight of the kayak.
: I've always found this argument somewhat flawed, because you almost
: never have a paddler that weighs exactly X weight, nor do you
: know exactly how much gear he's going to carry, how heavy his
: paddle is, lifevest is, tow rope, VHF radio, nor do you know
: what kind and how much camping gear/food, etc. he's going to
: bring with him, nor how big of a first aid kit, what fittings
: he's going to use, etc... Or if he's going to use it unloaded
: one day and loaded the next. When I design a kayak, I design it
: for range of weights and expect it to perform somewhat similarly
: at different weights. Knowing that it will be less responsive at
: heavier weights. Ideally, the paddler wants a kayak that fits
: right with the height and size of the cockpit area reflecting
: the paddler's size. That fit is far more important than if the
: build comes under the designed weight. Although, it's a given
: that you want to match the paddler with the right-sized boat.
: It's always easier to add weight than subtract.

: On a kayak build, we talking about a difference of 15 lbs. either
: way, which is 15 lbs less that the paddler has to yard around if
: it comes in lighter. I'd be very suspect of a design that
: couldn't handle that range either way.

: :so that a novice paddler may not judge the boat to be as stable

: On Stability: Typically, stability curves are higher for lighter
: weights. An example included below. Stability curves don't
: always transfer to reality, but a reduce of 25 lbs. in weight on
: a sea kayak typically translates to a 1/4-inch difference in
: waterline. It really takes about 50 to 100 lbs, to really change
: the feeling significantly. For kayaks builds, we're discussing
: the difference between a 50 lb. boat and a 35 lb. boat. Those
: difference make a difference to responsiveness and efficiency,
: but not so much on stability.

: :If a customer wants a lighter, more responsive kayak, I prefer to
: design it to meet those requirements by changing the parameters
: like increasing waterline breadth, adding rocker, changing hull
: shape, etc. Thsi way it should perform as designed.

: Yes, you can design for responsiveness and the chosen design should
: reflect the intended usage, but that's not relevant to my point.
: When comparing the same hull to the same hull at different
: weights, a kayak can be more responsive. For example, my NDK
: Explorer is far more responsive when unloaded than loaded. It
: works well in both states though. When coming through surf
: landing a heavily loaded boat, I'll take any extra
: responsiveness that I can get. Responsiveness isn't just
: displacement, it's also the total weight working against the
: force you place on the paddle. If you yard around more weight,
: it takes more force to perform the same maneuver than with a
: lighter boat. This also means that if you use the same force it
: would take to maneuver a heavier kayak and apply it to the
: lighter kayak, it's going to react quicker and go further.

Messages In This Thread

Strip: How necessary are stems?
Rob -- 12/8/2011, 8:17 am
Re: Strip: How necessary are stems? *PIC*
Don T -- 12/8/2011, 8:27 am
Re: Strip: How necessary are stems?
Clayton Plunkett -- 12/8/2011, 8:42 am
Re: Strip: How necessary are stems?
Ian Cummins -- 12/8/2011, 9:27 am
Re: Strip: How necessary are stems?
Paul Tavenier -- 12/8/2011, 12:52 pm
Re: Strip: How necessary are stems?
greg h -- 12/8/2011, 3:56 pm
Re: Strip: How necessary are stems?
Paul Tavenier -- 12/9/2011, 12:50 am
Re: Strip: How necessary are stems?
Bill Hamm -- 12/11/2011, 2:38 am
Re: Strip: How necessary are stems?
Bill Hamm -- 12/11/2011, 2:45 am
Re: Strip: How necessary are stems?
Mike Savage -- 12/11/2011, 9:02 am
Re: Strip: How necessary are stems?
Rob Macks/Laughing Loon CC&K -- 12/8/2011, 12:44 pm
Re: Strip: How necessary are stems?
Rod Tait (Orca Boats) -- 12/8/2011, 4:17 pm
Re: Strip: How necessary are stems?
Kurt Maurer -- 12/8/2011, 6:55 pm
Re: Strip: How necessary are stems?
Dwight Lynn -- 12/8/2011, 7:13 pm
Re: Strip: How necessary are stems? *PIC*
Kurt Maurer -- 12/8/2011, 7:56 pm
Re: Strip: How necessary are stems?
Dwight Lynn -- 12/8/2011, 10:13 pm
Re: Strip: How necessary are stems?
Kurt Maurer -- 12/9/2011, 10:06 am
Re: Strip: How necessary are stems?
Bill Hamm -- 12/11/2011, 2:44 am
Re: Strip: How necessary are stems?
Rod Tait (Orca Boats) -- 12/8/2011, 7:44 pm
Re: Strip: How necessary are stems?
Allan -- 12/8/2011, 8:57 pm
Re: Strip: How necessary are stems?
Rob -- 12/9/2011, 8:14 am
Re: Strip: How necessary are stems?
Kurt Maurer -- 12/9/2011, 10:13 am
Re: Strip: How necessary are stems?
Bill Hamm -- 12/11/2011, 2:42 am
Re: Strip: How necessary are stems?
Bryan Hansel -- 12/9/2011, 11:59 am
Re: Strip: How necessary are stems?
Rod Tait (Orca Boats) -- 12/9/2011, 1:16 pm
Re: Strip: How necessary are stems? *PIC*
Bryan Hansel -- 12/9/2011, 2:28 pm
Re: Strip: How necessary are stems?
Rod Tait (Orca Boats) -- 12/9/2011, 3:38 pm
Re: Strip: How necessary are stems?
Bryan Hansel -- 12/9/2011, 3:51 pm
Re: Strip: How necessary are stems?
ScottBaxter -- 12/9/2011, 5:11 pm
Re: Strip: How necessary are stems?
Bryan Hansel -- 12/9/2011, 6:01 pm
Re: Strip: How necessary are stems?
ScottBaxter -- 12/9/2011, 8:12 pm
Re: Strip: How necessary are stems? *PIC*
Bryan Hansel -- 12/9/2011, 11:51 am
Re: Strip: How necessary are stems? *PIC*
Bryan Hansel -- 12/9/2011, 11:51 am
Re: Strip: How necessary are stems? *PIC*
Bryan Hansel -- 12/9/2011, 11:53 am
Re: Strip: How necessary are stems?
Dan Caouette (CSFW) -- 12/9/2011, 1:32 pm
Re: Strip: How necessary are stems?
ancient kayaker -- 12/10/2011, 7:37 am
Re: Strip stems and weight
Will N 2 Go -- 12/11/2011, 11:29 am
Re: Strip stems and weight
Bill Hamm -- 12/13/2011, 4:55 am
Re: Strip stems and weight
Bill Hamm -- 12/13/2011, 5:00 am
Re: Strip: How necessary are stems?
Etienne Muller -- 12/11/2011, 5:01 am