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Re: S&G: Scaling
By:jagiven
Date: 10/14/2010, 11:29 am
In Response To: Re: S&G: Scaling (Dave Houser)

Thank you for the tips and pointing out some additional options that I frankly had not thought of. I have looked at a few of the different SOF boats such as the Kidarka. Long time ago I had considered making a SOF boat, but never did. This might be a good practice boat. Next week I will have to pull out a few of my SOF books and look them over. When reviewing the Kidarka I have to admit I did not remember what the acronyms (terms HB & HAB) used in the offsets (more homework).

With the scaling information given; I reviewed the 17LT. With a scale of 82%, I took a couple of quick measurement conversions and that will keep the deck ht ~10”, beam @~19”, L @ ~14’, paddler wt ~88-121 lbs, cargo wt max ~ 165 lbs. I picked 82% based on the deck height using the Kidarka as a base line, any lower than that I think it would be difficult for him to get into.

As of today he might be a little small for a scaled down CLC 17LT, but at the rate he is growing he probably fit in it by middle to late next summer. He is bigger than two of his cousins who are 9 & 11.

: Scaling S&G kayak must be done in all three axis the same
: proportion or the panels will not fit together properly.
: However, the thickness of the panels is insignificant compared
: to their length and width so they only need to be proportionally
: changed in the length and width to still fit together snugly.
: The volume and displacement of a kayak depend on all three
: dimensions of a kayak (length, width and height) so the
: displacement will vary by the proportionate change of the
: length, width and height, of the kayak, multiplied together, and
: remember, all three proportions must be the same. So if you
: scale the dimensions of an S&G kayak to, say, 70% the
: displacement will become .70 x .70 x .70 of its original
: displacement or .343 of its design displacement.

: Let’s look at the CLC Chesapeake 17LT. Its over all dimensions
: are 16’11.5” x 23.5” and paddler weight of 160-220 pounds
: and maximum payload of 300 pounds. If we scale it down to 70%
: its dimensions become length = .70 x 16.96 ft = 11.8 ft. and
: width = .70 x 23.5 in. = 16.5 in. The minimum paddler weight =
: .70 x .70 x .70 x 160 lbs = 54.9 lbs and the maximum paddler
: weight = .70 x .70 x.70 x 220 lbs = 75.5 lbs. and maximum
: payload weight = .705 x .70 x .70 x 300 lbs = 103 lbs. When
: scaling an S&G down too much the kayak becomes too narrow
: and too tipsy.

Messages In This Thread

S&G: Scaling
jagiven -- 10/12/2010, 8:07 pm
Re: S&G: Scaling
Bill Hamm -- 10/14/2010, 9:36 am
Re: S&G: Scaling
Dave Houser -- 10/14/2010, 4:57 am
Re: S&G: Scaling
Dan Caouette (CSFW) -- 10/14/2010, 6:27 pm
Re: S&G: Scaling
jagiven -- 10/14/2010, 11:29 am
Re: S&G: Scaling
Bill Hamm -- 10/14/2010, 9:42 pm
Re: S&G: Scaling
Johne -- 10/13/2010, 12:42 pm
Re: S&G: Scaling
Bill Hamm -- 10/14/2010, 4:40 am
Re: S&G: Scaling
george jung -- 10/13/2010, 4:03 pm
Re: S&G: Scaling
Bill Hamm -- 10/13/2010, 8:27 am
Re: S&G: Scaling *PIC*
Charles Robinson -- 10/13/2010, 9:49 am