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Re: S&G: Scaling
By:Dave Houser
Date: 10/14/2010, 4:57 am
In Response To: S&G: Scaling (jagiven)

: I own a CLC Chesapeake 17LT plan, but
: it is really too big of a boat for him to handle. Anyone have
: any tips on how to scale it down to for him. I am sure there is
: some ratio between the linear affect of shortening the boat and
: the cubical affect on its volume, but I do not know it.

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