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Entry #7

VAGABOND

drawings - stats - boat - budget - explanation - bio

Drawings:

Stats:

28'-4"
  L.O.A.
27'-8"
  L.W.L.
4'-4"
  Beam
41"
  W.L. Beam
5"
  Draft
1200#
  Displacement
800#
  Trailer weight
85 S.F.
  Wetted surface
0.5
  Prismatic Coefficient
333
  Pounds/inch immersion
28.7#

 

Wave & friction drag @ 6.15 mph (2.75 m/s)

Boat:

Introduction

I could have floated a significant part of this trip in an inner tube in the time I’ve spent thinking about this contest. Not that I’m complaining, this has been one of those projects to diddle with a bit and then put away for a while, then pull out and ruminate some more. Simply delicious.

A few assumptions were made and dictated what follows.

(a) The distance is 2400 miles more or less; if more its just more sightseeing.
(b) Only a fool or the truly desperate will run a boat down an unfamiliar river at night.
(c) Water flows downstream, but the wind doesn’t necessarily.
(d) No matter how grand an adventure this is, there will come a time when our intrepid couple will want nothing more than a hot shower, a meal prepared by others and a real bed.
(e) An igloo ultracold 50 icechest will keep ice for five days.
(f) The five dams we have to traverse were built by the Corps of Engineers and have public parks at the dam with a boat ramp. There will be a launch area downstream with connecting roads.

The decision was quickly made to use a hybrid gas/electric power system for propulsion. 2400 miles is over fourteen Ruta Maya races or nine Texas Water Safaris back to back. A long way to paddle or row. Sails’ out, see (c) above.
The Boat

Think long, lean and light. Vagabond started out as a blend of NW trapper canoe, sampan and Texas (Water Safari) racing canoe. The basic concept is a boat that will move quickly and very efficiently, requiring little in the way of power. I couldn’t justify the effort to build an elegantly formed stripper for what would probably be a one shot boat and the design slowly evolved to its current form. The second great liberation happened when I gave up trying to provide a double berth for our intrepid couple and the boat became more balanced and easily driven.

Deceptively simple, the hull is a basic flat bottomed platform of ¾” T&G plywood with sides of parallel cut 3/8” ply tied and taped, pretty quick and dirty. But, when all is said and done Vagabond can slide down the river at six to six and a half miles every hour leaving the least of ripples behind as a wake, about an eighth of an inch high according to Mitchlet.

The superstructure started out as a Conestoga wagon style canopy and slowly evolved into the parallel ridgepole scheme shown. The ridgepoles leave an open slot making it easy to stand and walk back and forth while keeping the standee centered in a relatively narrow boat. The ridgepoles also form the backbone of a button-down adaptable covering able to cope with a driving rain or opened up for more physical and psychological space for an evening tied up along the bank of the mighty Mississippi. In between the covering can be rolled up out of the way or partially unfurled to provide some shade for those glorious sunshiny days when this is a golden trip.

Propulsion

The hybrid gas-electric power scheme was decided on early in the process primarily because I liked it and thought I could make it work. A secondary consideration was all that electricity would be handy when we drag ourselves up on dry land.

Not having the research and development budget of say Honda, we’ll just use some of their and others off the shelf components and marvel at how well they work together. Still water and gentle wind, the specified trolling motor will loaf us along at six to six and a half miles an hour at 25-30 amps. The six-volt golf cart batteries would run the motor for 6-7 hours before needing a charge. I envision running on battery power about 4 hours a day and running the homebrew genset the other 4 hours providing amps for the trolling motor and charging the batteries at the same time. Your mileage will vary. Worst will probably be crossing the lakes in windy conditions. There will be times when finding shelter is the best of all possible choices. I’m not sure whether it would be best to run the genset continuously half a day or in several shorter sessions, but in either case it will take about a gallon of gas a day. The ample battery capacity has the side benefit of providing power for a fan on those still, muggy nights and anchor/navigation lights when necessary.
Portages

Simple swing arm suspension evolved right from the start, and then. An upgrade to the wheels/bearings and it’s a built-in trailer. With a trailer coupler stuck in the stern, a low power dolly, powered by a 2 speed 14volt cordless drill will walk the boat right out of the water. The dolly probably won’t be necessary if our intrepid couple spend a little time online, they should find the three to five volunteers that live near the dams that would be happy to lend a trailer hitch.

I’d be embarrassed to tell you how long I worked on schemes to drag the boat out of the water bow first before I realized the boat could come out of the water stern first, just reverse of the way it goes in to begin this adventure.

Operation

50 mile days more or less with resupply at roughly 5 day intervals, water, food, fuel and ice. Early shoal water runs would probably be done with a sweep off the stern to keep Vagabond straight, though the trolling motor might do the job if the water’s deep enough. The sweep could also serve as mast for a downwind sail for those that just have to have a sail. Majority of time Vagabond will be sliding down river with the current, one person at the helm and the other in the forward stateroom lounging in a camp chair.

Budget:

Click Here

Explanation:

The first item is to provide a twenty- percent contingency to cover taxes, shipping, fasteners, Murphy etc.

Most of the items in the budget are self-explanatory, but here are a few comments.

To keep cost down, as many components as possible would come from general-purpose sources; in as large a quantity as required.

The transport cost (super shuttle) to Fort Benton and pickup in New Orleans is a wild ass guess tempered by where our intrepid couple travels from and depends on the help of family or friends. Fortunately, there’s no trailer cost involved.

There is just a touch of welding required on the swing arms, but I’ve unilaterally decided there’s a mechanics/metal-working shop with sympathetic instructors at our school teachers school.

The weights listed are typically shipping weights where applicable

Bio:

Milton "Skip" Johnson

Skip is an archetect who lives in Houston, TX. He has designed numerous boats including several for the Texas Water Safari. He has entered almost every contest Duckworks has held.

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