Scaling down canoe plans ?

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HighPlainsDrifter
Posts: 70
Joined: Tue Mar 22, 2011 9:30 pm
Location: Brookings, SD USA

Scaling down canoe plans ?

Post by HighPlainsDrifter » Tue Oct 13, 2015 2:25 pm

Lets say, I want to build another canoe and that I have a perfect model of what I want that canoe to be (if only in my head).

I have a 15' Prospector Ranger and I do love the way that canoe handles both tandem and solo...... that is my model of perfection. But, what I would like is a smaller solo "play boat" for just dinking around. Maybe this solo canoe would be 13' (just saying)

Chestnut Canoe Company built a line of canoes called the Prospector. From what I understand is that the hull lines (shapes) of these canoes were all the same (similar) but differed in size. Their line of Prospectors canoes were:

Forest 12'
Fire 14'
Ranger 15'
Fort 16'
Garry 17'
Voyageur 18'

Ted Moores book has the table of offsets for both the "Fort" and the "Ranger". Is it just a simple matter of reducing the offset values by a certain fraction to create a smaller canoe having the same shape??? ......... for example a 13' Prospector could be created by multiplying the 15' plans by 0.87 (13/15)

Or is it possible that Tables of Offsets might exist for the smaller canoes of the Prospector line ?

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Jim Dodd
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Location: Iowa

Re: Scaling down canoe plans ?

Post by Jim Dodd » Wed Oct 14, 2015 9:49 pm

I'm sure someone has the smaller table of offsets.
But as they say "There is more than one way to skin a cat!"

I have taken my own plans to a good print shop, and had them computer enlarged or reduced. It worked great ! It was also very reasonable !

Remember to reduce form spacing accordingly.

You could also do it with graph paper.

Good Luck ! I love modifying plans, but care needs to be taken !

Jim
Keep your paddle wet and your seat dry!

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HighPlainsDrifter
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Joined: Tue Mar 22, 2011 9:30 pm
Location: Brookings, SD USA

Re: Scaling down canoe plans ?

Post by HighPlainsDrifter » Thu Oct 15, 2015 8:56 pm

Jim
Thank you. Thank you. It is great to have a person with first hand experience, share that experience.

After I made my post, I thought about reducing my plans on a copy machine and adjusting my form spacing appropriately (as you say). Knowing that you have had success is encouragement to forge ahead and that is what I will do. With modified plans of the Ranger I will have a way to look at her lines in comparison to other canoes that I am thinking about.

The following day I had the plans of the Ranger that I lofted (from Ted's Table of Offsets) reduced to 85% (approx a 13' Prospector). I then had the printer do a mirror image print of the reduction. When I put the two halves together I could see a canoe that looked pretty nice with a 30" max beam and bow shear at 19". I am thinking that setting the stations for a 13.5' canoe might give me the canoe that I am thinking about........ maybe.

There is always danger in playing with established plans. If I cut the molds and set them up, I will know if I should continue.

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