Fixed Ballast for Shackleton

Water or fixed ballast?

Scamp is designed to take on approximately 175 lb. of water as ballast.  I never felt quite right about this design characteristic.  Though I appreciate the concept of water ballast in larger sailboats (where weight savings can be over 1,000 lb.) I question whether the benefits are realized in small sailing vessels. If you want the lightest trailering rig possible, then water ballast proves to be advantageous.  However, to me, Scamp is such a light sailboat, that to add fixed ballast doesn’t seem to present any real problems or huge disadvantages.

Some of the draw backs of water ballast may include:

  1. Drilling a hole in the bottom of the boat to bring in water.
  2. Maintaining the water tank from algae or microbial growth.
  3. Transporting invasive larvae (think quagga mussels here.)
  4. Sealing the water tank from surrounding water tight compartments inside the boat.
  5. Accessing the drain hole each time you sail.
  6. Toping off the water tank with additional water (gravity doesn’t’ completely fill the water chamber) each time you sail.
  7. Draining the water tank after each sail.
  8. Drying the water tank from residual water after each sail.

Some of the advantages of fixed ballast may include:

  1. Never forgetting to fill the ballast tank before setting sail.
  2. No maintenance, with dry ballast I can fix it and forget it.
  3. No water sloshing around to potentially destabilize the boat.
  4. Dryer cockpit sole.  I know I would spill water each and every time I top off the water tank with a pitcher of water.
  5. Lower center of gravity.
  6. Adjustable by adding or removing additional plates as needed.
  7. Storage of additional heavy gear in this same BH area.

For these reasons, I’ve decided to add 150 lb. of fixed ballast in Shackleton.  Why 150 lb.?  I’m simply guessing that 150 lb. fastened directly to the bottom of Scamp is worth at least 175 lb. of water dispersed over the entire water tank area.  With these ideas rattling around in my head, I visited Pacific Steel for my ballast needs.  DSC01000DSC00991DSC00998DSC00997DSC00004 I had them cut 6 pieces of flat bar, measuring 3/4″ x 6″ x 20″.  Each of these plates weigh 25 lb.  This will give me 153 lb. of ballast in the bottom of my boat.DSC00002Cleaning up the rough edges.   DSC00005DSC00006  Coating all sides with two coats of graphite epoxy.  I will then build a wooden box to hold the plates.  This box will be glued to the bottom of the hull.

Summary:

I’m hoping these changes will simplify and quicken my sailing experience.  Anytime I can simplify my life, I’m usually happy with the results.  Hopefully these changes will bring about similar results.

Box design to follow.

 

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2 thoughts on “Fixed Ballast for Shackleton

  1. Brent –

    Think about the stresses, trailering etc, when out of the water. Hulls are designed to have water pressure “upward” counteracting the mass “downward”

    I’d highly recommend shooting an email to John Welsford to get structural reinforcing input. He over-designs his boats for stress but his input would be highly desirable.

    He’s in Port Townsend this week and the next for the SCAMP Camp and the Red Lantern Rally but I think he’s answering emails at jwboatdesigns (at) xtra (dot) co (dot) nz
    Remember to correctly rephrase the email address above.

    I’ll try to remember to ask him to look for your email on the ballasting issue.

    I do like your thinking…

    Simeon (Noddy, SCAMP #11)

  2. Simeon,

    Good suggestion. Email sent. Also, did you ever get a chance to shoot a rigging video? I would find such a video very helpful.

    thanks,
    Brent

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