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

: I am considering building one of Putz's Walrus's and have gone through the
: archives, but may have missed the answers to my questions.

: First question: What are the beam widths of each Walrus (W1 and W2)?

: Second: Has anyone shrunk one of the designs down to 13' to 15' in length?

: I am looking to build one of the Walrus's but shrink it down to about 15',
: though I may consider shrinking it further to 13' (although I believe I
: would probably build Clark Craft's BK#10 design and elongate it to 13'
: with a 30" beam). Since I am a heavier paddler (285 lbs.), I believe
: I need a beam of about 30" for either sized boat. If neither of the
: Walrus's have close to a 30" beam (I would consider 28" to be
: close, 26" to not be as close as I would like) has anyone increased
: the beam?

: I may be opening up a proverbial can-o'-worms here, but is there a rule of
: thumb for "Greenland" style kayaks, like Putz's Walrus, Clark
: Craft's BK10, etc. for length vs. beam width for load capacity. I ask
: because I compared CC's BK10 to Folbot's Yukon kayak and they are rated
: for the same load (300#). Either CC is overly optimistic, Folbot is overly
: cautious or something in the middle because the BK10 is 11' long with a
: 28" beam vs. the Yukon being 13' with a 30" beam. Or perhaps
: they really are that different despite them being very similar looking to
: the casual observer.

: If it matters, I am planning on using it mostly in flat water, inland rivers
: and streams, although possibly where one river near me is close to going
: to a large bay and is approx. 1 mile across.

: Thanks,
: Paul