Modular Test Bed

I am almost ready to make my next boat.  Almost.   Honestly, I simply can’t believe how much this choice has been vexing me.  I’ve been pondering the question for at least a decade, and seriously so over the past two years.  In that time, I’ve changed my mind… constantly.

Why?

This could be my last boat.  Chose well.  Ack!  And… for the past decade I worked for a nightmare of a boss.  I dreamed of escape.  Often I dreamed of crossing the Atlantic Ocean in some crazy small craft. Other times I dreamed of boat trips across the waterways of the country, trips that would take months.  Escape.

Now I am retired.  I have nothing to escape from.   So… what do I want?  Well, I’ll share more about that soon.  In the meantime, I do a small build for fun, one that could serve as a dinghy, of sorts, for whatever big boat I build next.

I’m designing and building a modular pontoon.   Build a dozen or more sections and put it together in any way I chose.

Here’s my first configuration:

Numbers for each pontoon:

  1. 3 feet long – length of each pontoon
  2. 7.75 inches wide and deep (dimensions of each side of a pontoon.)
  3. But first, calculate with the pontoon only 4 inches deep.

Here’s the math:

Results

  1. One full pontoon = 41 pounds of flotation each.
  2. One-half pontoon (end pontoon) = 20 pounds
  3. One front and one back pontoon = 40 pounds
  4. One center and two end pontoons = 81 pounds.  Multiply by two assuming a raft with two pontoons. = 162 pounds flotation.

So… to float 280 pounds – me plus a bunch of “stuff”

Two pontoons

  1. 4 end pontoons = 80
  2. 6 center pontoons = 240 pounds – 3 on each side
  3. 8 pontoons at 3 feet long each = two pontoons at 24 feet long

or

Three pontoons

  1. 6 end pontoons = 120 pounds
  2. 6 center pontoons = 240 – two on each of three pontoons
  3. 12 pontoons = 360 pounds buoyancy – 3 pontoons with 4 each is 12 feet long.
  4. Possible width – assume each pontoon is 8 inches wide. With 8 inches between each.   24 inches of pontoon plus 16 = 40 inches wide

Or, assume 5-inch submersion of each pontoon. Much better results.

So… to float 280 pounds – me plus a bunch of “stuff”

Two pontoons

  1. 4 end pontoons = 100 – 25 pound each.
  2. 4 center pontoons = 204 pounds – 2 on each side
  3. 4 pontoons at 3 feet long each = two pontoons at 12 feet long

304 pounds buoyancy.

This clearly works better.  Note that I haven’t figured in the weight of the boat itself, but there is plenty of buoyancy left in the calculations.

More details coming.

One Comment

  1. I love the concept and the calculations that go with it. Very cool!

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