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 Post subject: Re: Guidelines for scaling drawings?
PostPosted: Tue Jan 31, 2012 5:36 pm 
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Joined: Mon Sep 12, 2011 6:29 pm
Posts: 139
Location: Chicago
Thanks for the advice. I hereby cancel my scaling-down venture.
Maybe I can modify my storage area to accommodate JEM’s 15’ 3” Trapper.
The Laker is beautiful but too much decking for me; more kayak than canoe.


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 Post subject: Re: Guidelines for scaling drawings?
PostPosted: Tue Jan 31, 2012 5:45 pm 
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Joined: Fri Jun 18, 2004 8:14 pm
Posts: 4855
Location: Greensboro, NC
I'll try and have a look at it later this week.

This is a really busy time of year for my family. My daughter's basketball team has their last game Thursday (13-0 so far and clinched at least a share of the conference title. Go Cougars!!!). So things in our house will slow down a bit.

Feb 25 is the last game of the youth league team I coach. After that, more time for boat designs.

_________________
-Matt. Designer.


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 Post subject: Re: Guidelines for scaling drawings?
PostPosted: Tue Jan 31, 2012 11:29 pm 
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Joined: Wed Feb 21, 2007 10:48 pm
Posts: 988
Location: Tx
Les
I think you will be happy with your choice.
I started yaking in a 9 ft 5in yak (plastic) and from there to a 12 fter then a 15 fter now a 17 ft 2 in NW , in every cast the length has helped in the speed tracking, ride stability ,now to me a 16 fter is about as short as I want to go.
Loading and hauling a yak that is 15 ft isnt much different than a 13 fter.
Ron


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 Post subject: Re: Guidelines for scaling drawings?
PostPosted: Tue Feb 07, 2012 10:47 pm 
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Joined: Mon Nov 12, 2007 8:12 am
Posts: 192
Location: S.E. Queensland
I did make my last one a bit narrower and a bit lower. 2 inches and 1 1/2 inches respectively. Just out of personal preference. Didn't attempt to scale anything just stitched it together as per the plans. Marked out where I wanted it to end up took it apart and began cutting :D Had to fiddle a bit with making it all come fair again and the boat might well be a tad longer than it started out because I "closed" the side panels up a bit. The angle of the sides might not be exactly as intended either, but I am still very happy with the result. Had to alter the sizes and angles on the frames to suit as I went along. But pretty much I just winged it. Also increased the VEE bottom aspect.
I did this because when I see some of the bigger guys in these boat that still appear, to me anyway, to have too much freeboard. I'd be about 150 lbs wet through. Just a personal preference, and hopefully less of a wind signature. Funnily enough once I had lowered the sides a bit I then proceeded to make the front deck higher by increasing the curve depth. It still looks fairly well balanced. I reckon the original round decked okwata design suffered because of the "blandness" of the deck being all the same from one end to the other, like a section cut out of a piece of pipe. I even lifted the bow and stern a bit to help overcome this.
This probably isn't an ideal method as far as scaling goes, but so long as you end up close to what you want the ony risk is to a few sheets of plywood.
Cheers John.


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 Post subject: Re: Guidelines for scaling drawings?
PostPosted: Wed Feb 08, 2012 10:34 am 
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Joined: Mon Sep 12, 2011 6:29 pm
Posts: 139
Location: Chicago
Thanks for the reply John.
Glad you're happy with your modifications; however, as you say, to change some dimensions or angles and leave others as designed is not scaling; if I were to shorten the length of a canoe design, I would not consider it 'to scale' unless I changed every dimension correspondingly, top to bottom and bow to stern; if everything does not end up exactly to scale, then I would be losing the advantage of a professional design. To do so would be taking the plans for a JEM Trapper canoe and building something that is NOT a 'JEM' Trapper canoe. The first boat I built was done totally by 'winging it' and by untrained, unexperienced intuition -- it turned out terrible -- that is why I intend to build my canoe by following professionally designed plans - if not strictly 'as designed', then strictly 'to scale'.
As it turns out, my storage area will accommodate the 15'3" x 35" canoe after all, and it will fit through my basement windows, so I have no need to scale down the canoe.


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 Post subject: Re: Guidelines for scaling drawings?
PostPosted: Wed Feb 08, 2012 7:58 pm 
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Joined: Mon Nov 12, 2007 8:12 am
Posts: 192
Location: S.E. Queensland
Not intended as a method of scaling. It was all about ending up with a boat that was closer in a few aspects to what I wanted. Which was what you wanted after all. If you're gonna go to the trouble of building a boat, or anything else for that matter, why not incorporate a few of your own preferences? When I did the cockpit I went back to my Laker cockpit and used it to work out exactly how I would PREFER a cockpit to be that would suit me. Taped a cardboard cutout over the laker and made enough space around me for me to fit easily and any gear I would be likely to want in there. That made the cockpit scaled to me. I know a few people that would realy struggle to get in and out of it. The hatches were made to accept the largest item I would probably ever try to put inside them without that item getting jammed.
Regarding any differences I may have made to the dynamics of the boat that would obviously be my problem and I certainly could not complain to Matt if the boat decided it would travel slower, be less stable, track badly or whatever. But that's ok I allowed for the fact I have reasonable balance and could adjust stability with seat height. I would imagine the actual differences I made, probably apart from stability would be negligible. The boat paddles well and suits me.
I spose I'm just saying don't be afraid to waste a bit of plywood for the sake of not getting what you realy want. I don't believe I was taking a liberty with Matt's design as it was one that had been discontinued and I'm sure Matt would agree it did not prove popular. I just saw potential and worked on that. A boat ended up being built that otherwise would not have been.
Cheers John


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