Date: 5/21/2003, 8:44 am
: Putz's book didn't give widths but I took measurments from the plans and
: tried to calculate the widths and got 21" (fairly narrow) and
: 25.5". Don't know if I got it right.
: In kayaking terms you are a max load even before you put your pfd on. A 13
: ft. boat would have to be 40 in. wide to support someone with your heft.
: You can build your boat to whatever width you prefer but it will have to
: be fairly long or you'll have the waterline up around the cockpit rim. We
: are all prisoners of Archimedis Law. The push up has to be a little more
: than the push down. The push up is provided by the water you displace
: which means a big boat for a big paddler.
: When a designer like Percy Blandsford (of the BK series) sets a load limit I
: don't think he envisioned a max load every time the boat hits the water.
: When you suit up to paddle you and your gear could be in excess of 300
: lbs. A constant load that size will flex the hell of the frame over time.
: Therefore, strong lumber and heavy lashings.
: Skin boats don't have the margin for error that their plastic cousins enjoy.
: By building bigger on all dimensions you will have a safer boat.
: Charlie
Charlie,
Thanks for the response. Perhaps I mistyped, but the BK 10 is 11' long and rated for 300 lbs. and has a beam of 28", if I remember the beam correctly. I figured that increasing the length and beam dimensions to 13' and 30" respectively should increase the load capacity to at least 350# (which should give me a bit of a factor of safety that I am looking for), but I don't have any calculations to back that up. I wanted to lengthen and widen to get keep the same draft (whatever that may be with the original design) but increase the load capacity to something that is more reasonable for me, a larger paddler. And I was using this design as it is close to the Folbot/Klepper style that I feel I am comparing apples to apples, although it is hard to know that for sure since I have neither built the BK10 or seen a Folbot in real life. I am strictly judging that they are both close to be apples based on pictures. I also hope to not need to push my kayak to its weight limit since paddling will be a part of my weight loss program and since I will be building rather late in the season (wife says I need to finish the basement repairs first), I may not even get it completed in time to use before next spring, by which time I am hoping to be weighing in no heavier than 250#.
The question I have, how do you base the 40" beam? What weight load are you using, what calc's are you using or what boat are you using to base the 13'x40" load capacity? If I am stuck at a 40" beam at 13', then I would just build CC's 15' double that has a 30" beam (can't recall which BK# it is offhand) and modify it for a single paddler. As I recall, it has plenty of carrying capacity (500#, I think) for my current heft. 15', IMHO, is about the limit that I find acceptable for a single person canoe/kayak that is used for recreational paddling.
Paul
Messages In This Thread
- Skin-on-Frame: Walrus Q's
Paul Probus -- 5/20/2003, 2:20 pm- Re: Skin-on-Frame: Walrus Q's
Bill Price -- 5/21/2003, 11:22 am- Re: Skin-on-Frame: Walrus Q's
Paul Probus -- 5/21/2003, 12:46 pm
- Re: Skin-on-Frame: Walrus Q's
Paul G. Jacobson -- 5/21/2003, 1:30 am- Re: Skin-on-Frame: Walrus Q's
Paul Probus -- 5/21/2003, 9:17 am- Re: Skin-on-Frame: Walrus Q's
Paul G. Jacobson -- 5/22/2003, 12:25 am- Re: Skin-on-Frame: Walrus Q's
Paul Probus -- 5/22/2003, 11:46 am
- Re: Skin-on-Frame: Walrus Q's
- Re: Skin-on-Frame: Walrus Q's
- Re: Skin-on-Frame: Walrus Q's
C. Fronzek -- 5/20/2003, 8:53 pm- Re: Skin-on-Frame: Walrus Q's
Paul Probus -- 5/21/2003, 8:44 am
- Re: Skin-on-Frame: Walrus Q's
- Re: Skin-on-Frame: Walrus Q's