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. A 4-panel design. My own Ross Lillistone Flint is also a 4-panel 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 ‘tidily’ but as soon as the chine gets into the water, they become very stable.


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."

Specifications as Jim Designed Her:

  • Length: 14' (4.3 m)
  • Beam: 45" (1143 mm)
  • Weight:  60 pounds (27.2 kg)
  • Water Line Length: 12' 6" (3.8 m)
  • Water Line Width: 36.5" (927 mm)
  • WLL/WLW Ratio: 4.1:1
  • Hull Speed: 4.7 knots, 8.7 kph, 5.4 mph

Conversion to an Oar Cruiser

  • Lengthen the hull to 16' (4.9 m) by adding a 2' section midships in order to increase capacity and increase Hull Speed to 5.1 knots (9.5 kph, 5.9 mph).
  • Lowered the top of the stem 9" (229 mm), raised the sheer at midships by 3" (76 mm), lowered the top of the transom by 5" (127 mm) and drew new sheer line intersecting these three points to create a reverse sheer.
  • Used full-sized bulkheads at stations #3.75, #5.25 and #10, each crowned 1" (25 mm).
  • This created 2 forward compartments 3' 9" (1143 mm) and 1' 6" (457 mm) long, a 6' 6" (1981 mm) cockpit and an after compartment 2' 6" (762 mm) long.
  • Added a forward deck extended to the top of the bulkhead at station #3.75.
  • Added an after deck 2' 6" (762 mm) long.
  • Added side decks approximately 11" (279 mm) wide midships.
  • A forward hatch 24" (610 mm) by 33" (838 mm) long and an after hatch 24" by 36" (914 mm) long, both mounted on rails, were made so that the open compartments could be closed and the size of the cockpit opening could be reduced.
  • Floor boards were added to provide a dry support for the sleeping pad/bag.
  • The seat rests on two parallel struts and could easily be made to slide on rollers. If the foot brace was made to be locked during both the power AND recovery stroke, oars 12" to 18" (305 to 457 mm) longer than the recommended 8' (2438 mm) oars could be used.
  • Two bows were made that fit into sockets on the deck and can be stored in the cockpit when not needed. These bows support the shelter at night. 
  • These changes would bring Robote's weight to approximately 90 pounds (40.8 Kg). 

A Model Encompassing the Suggested Changes Above:


Robote with Reverse Sheer (This and the 3 photos below by T. Clarke)

Hatches Positioned to Maximize Cockpit Opening 

Hatches Fully Closed with Tent Installed on Bows

Hatches Opened to Enable Access to Storage

Summary-Pros:

  • Sliding hatches enable varying the size of the cockpit opening.
  • Large storage compartments are easily accessed.
  • Reduced windage (in cross winds) by using a reverse sheer.
  • Increased freeboard at cockpit, sliding hatches, fore and aft decks increase seaworthiness.
  • V-bottom, chines above the waterline and extended WLL all make this a faster Oar Cruiser.

Summary-Cons:

  • Added decks, bulkheads and hatches make Robote heavier and more difficult to car-top.

Morning Routine:

Her watch alarm woke her a half-hour before sunrise. She stretched for a couple of minutes, then rolled up her summer weight sleeping bag/pad and stowed them in the forward compartment. She inserted the propane tank of her Jetboil Stove in a purpose-made hole in the lid of her 'kitchen box' so that it wouldn't tip. In two-minutes she had boiling water for her mug of coffee. She pulled out the thermos jar she had prepared the night before with hot oatmeal and raisins. Using the foot brace as a backrest and a life preserver cushion, she sat back and enjoyed her breakfast; thinking about the next 34 miles down Tangier Sound that would take her to Onancock Creek where she would meet with friends.

4 comments:

  1. Between Robote and Flint which do you thnk would be more all round capable? Flint's ability to be rowed while fully swamped in the open version is persuasive for me

    ReplyDelete
  2. Hi Christopher. (sorry for the delay getting back to you... 'stuff' happens)
    I assume you are talking about a 'stock' Robote (NOT how I built the concept model)... Flint has built-in flotation under the foredeck and the 'seat' aft... Robote has no built-in flotation... this will make Flint easier to reboard and it will float a little higher (more freeboard) than Robote with no built-in flotation.
    Both boats would be a real bear to row when swamped!.. a swamped boat, unless it has flotation high up, is very unstable.
    On the other hand, Robote as a proposed OarCruiser, would be better if swamped because of 1) the side decks and 2) the flotation aft is higher up (deck level) than on Flint. Although I doubt you could reboard 'OarCruiser' Robote without shipping a lot of water (but not as much as Flint).
    Hope this helps... Tom

    ReplyDelete