Mark Wallace's Black Skiff

Sunday, February 26, 2017

CATCH: More on Car-topping

In a previous post, we discussed car-topping. Here's more information...

John Murray of Gaco Oar Locks and the Swift Dory wrote an article on car-topping... This is a photo from the article:

Extension Arm: One way to load a boat onto the car roof

If you car-top your boat, or are thinking about doing it, the article is worth your time.

Sunday, February 19, 2017

Michalak's Robote: Easy Build, Easy Row

Jim Michalak has designed a number of deep-V boats (no chines in the water) including Vireo (as an oar cruiser ), WeeVee a 7’ 6” (2.3m) dinghy and Robote. My own Ross Lillistone Flint is also a deep-V design. My experience rowing Flint and Vireo is that the deep-V design provides a fast hull with low resistance… initially a little ‘tiddily’ but as soon as the chine gets into the water, they become very stable.

Robote is really an extended Vireo… 14’ (4.3m) long, 45” (1.14m) wide, weighing approximately 60 pounds (27.2Kg) as designed.

Frank Kahr's Robote

Plans for Robote

Frank Kahr wrote (in the Duckworks Robote Page) about his participating in the “Blackburn Challenge” in his Robote…
"Wind was SE 15+, rising, with 2-3' chop off the ocean. I rowed about 10 miles, then ran for cover in Pigeon Cove. The alternative was several more miles of windward slog followed by more miles of crosswind. It would have been too much for me." 
"The boat was dry, in good control always. It will cope with conditions in which you have no business being out."
I built a concept model for an oar cruiser based on the Robote design.

Concept Model of an Oar Cruiser Based on Robote

Interior of the Robote Concept Model

Following are the changes and additions:

  • Re-shaped the sheer line in order to decrease windage at the ends of the boat and increase freeboard at the cockpit… lowered top of the stem by 5¼” (133mm), lowered top of the transom by 1” (25mm) and raised the sheer at section 8 (midships) by 3½” (89mm)
    Profile Showing How Windage was Reduced
  • Added a fore deck (crowned 2” [51mm]) 6’ 8” (2m) long, an aft deck, also crowned, 3’ 5” (1m) long and side decks 10” (254mm) wide. The ‘headroom’ under the aft end of the foredeck down to the top of the floorboards is 18” (0.46m).
  • Eliminated the temporary mold at section 5, added a permanent bulkhead at section 4 and converted the temporary mold at section 11 to a permanent bulkhead. Both bulkheads have large waterproof hatches for access to watertight storage compartments.
  • Added floorboards approximately 7’ (2.1m) long to the 7’ 6” ‘sleeping area. The cockpit opening is 4’ (1.2m) long, with a 3” (76mm) coaming on all four sides.
  • I added ‘hoops’ to support a ‘tent’ for rain protection at night and, when the sides are taken down and the ends are partially rolled up, sun protection while rowing.

The decks, large waterproof end compartments, increased freeboard at the cockpit all make this a rowboat that could be taken out in rougher conditions than most rowboats. Jim’s deep “V” hull makes for a boat that is very easy to row and that tracks well. Carrying capacity for equipment and stores, in waterproof compartments is high, sufficient for at least a week’s cruise.

I could envision a mid-fall cruise down Barnegat Bay, after most of the boats have gone to rest for the winter… anchoring off (or inside) the many state and national parks and wildlife refuges along the way… cool weather, no greenhead flies… plenty of interesting places to visit.

Love to see your comments below…

Sunday, February 12, 2017

Floor Boards (& Foot Rests)

In a July 2016 post, we presented Floorboard Alternatives. And frequently, for oar cruisers, we’ve recommended in this blog that floorboards be made from ‘slats’ arranged crosswise in order to provide adjustable anchor points for foot rests and a seat, and a dry sleeping platform.

This post is a description of floor boards and foot rests I made for my Ross Lillistone Flint.

My Ross Lillistone Flint, Raven

The slats in the floorboards are 1” by ½” (25mm by 13mm) Western Red Cedar. The two longitudinal struts (glued and screwed to every slat) are oak, ¾” x ¾” (19mm x 19mm).

The slats are spaced exactly ½” (13mm) apart to allow the cleats to hook under a slat.  The ends of every slat are tapered to the slope of the bottom. The floor boards (and foot rests) are finished in Exterior Watco Oil. Since there is a permanent rowing thwart, there was no need to make a separate, movable, rowing seat.

Floorboards Installed in Raven

I added a wedge to hold down the forward end of the floorboards to prevent them from lifting when pressure was applied to the foot rests. The wedge is jammed under a cleat used for the main sheet when sailing Flint.

Wedge to Hold Down Forward End of Floorboards

The footrests are made from 6mm Ocume, a single oak base (3/4” x 1.5” x 14” long: 19mm x 38mm x 356mm) and three aluminum cleats 3.5” (89mm) inches long, ¾” (19mm) high and ½” (13mm) deep. The three cleats are spaced so that they fit between and on either side of the longitudinal struts.

3 Aluminum Cleats to Hold the Foot Rests to the Floorboards

Foot Rests Locked to Floorboards

Back of the Foot Rests

The footrests and floorboards have worked very well. The footrests can be moved to any slat to accommodate different rowers or to adjust rowing geometry.

If I were to do it again, I’d make the struts (to which the slats are attached) bigger (deeper) to prevent the floorboards from bending up (slightly) when pressure is put on the foot rests. Other than that one change, I would use this arrangement in future rowing boats.

Questions and/or comments are welcome.

Sunday, February 5, 2017

Dories: Grand Banks

Grand Banks Dories are characterized by narrow bottoms, straight sides from chine to sheer and narrow ‘tombstone’ transoms. The original design (approximately 1830, 50 years after the Swampscott dory was first built) enabled the dories to be stacked and taken out to the Grand Banks fishing areas on schooners and then off loaded to one or two-man crews to fish for Cod and Halibut.

Stacked Dories (Source)

Towed Dories from Schooner Albert J. Lutz (Source)

Many designers have created variations of the Grand Banks Dories for recreational use, including Bolger, Michalak and Welsford.

Phil Bolger’s Gloucester Light Dory

Phil Bolger's Gloucester Light Dory, 15' 6" (4.7m) x 4' (1.2m)

Gloucester Light Dory Overview Plan

Phil Bolger...
"This is certainly the best design I ever made… When I come up for judgment and they stop me at the gate and ask, ‘What’s your excuse?’ I’ll tell them I designed the Gloucester Light Dory and they’ll have to let me in." (From Phil Bolger’s obituary in the Boston Globe)

Jim Michalak's Sportdory

Jim Michalak...
“Sportdory is an attempt to improve upon the Bolger/Payson dory I built about 15 years ago. This boat is slightly smaller than [that] dory. In particular the bow is lower in hopes of cutting windage. The stern is mostly similar. The center cross section is about identical. This boat has slightly more rocker than the original Bolger dory.” (Taken from Plans Description on Duckworks site)

Jim Michalak's Sportdory 15' (4.6m) x 4' (1.2m)

Overview Plan of Sportdory

John Welsford’s Light Dory Mk II

John Welsford…
“…a plywood dory with a tombstone transom (it’s not really a dory otherwise); a nicely curved stem to force some shape into the sides forward, a strong sheer kicking up aft to a high stern (thoughts of going surfing) with the maximum beam (further aft than is traditional to make the boat run straight in heavy following seas). Added to this is a big skeg for directional stability and to balance the windage, buoyancy tanks under the seats and a sculling notch in the transom…” (From plan description)
John Welsford’s Light Dory Mk II is 16’ 8” (5.14m) x 4’ 1” (1.26m)

Overview Plan of Light Dory Mk II

Also see Michael Storer’s article: "Are Dories REALLY Seaworthy"