Mailport July 2011 Issue

Mailport: July 2011

More Math Fun

I’m sure others have pointed this out, but ex-professors can’t let such things pass. Reader Tom Nies (Mailport, June 2011) is correct in his “You Do the Math” letter: The area of a circle is usually expressed as Pi times Radius squared (Pi x R2), and varies as the square of the radius. But if you substitute the diameter measurement, which is twice the radius (R=D/2) in the equation, you get Area=Pi/4 x D2, so your original statement that the area varies as the square of the diameter was also correct. Now you see why ex-math professors don’t get invited to many parties.

Tom John
Pandora’s Boat, New Horizon 25
Hudson, Fla.

Next: Rope Cleaning

Comments (1)

Hey. This letter is two jammed together with some text missing.

Regarding the epoxy testing, please also consider testing products from Progressive Epoxies ( The proprietor, Paul Orman, has a rather cacophonic website, but he seems to have a very good product line at practical prices. I'm doing a huge hull blister re-lamination using their "Premium No Blush" cycloaliphatic epoxy, and I'd love to know how that stacks up to West. I've never had trouble with West, but I want the best epoxy on my bottom & blush is just more work. Are non-blushing epoxies really a free lunch? I considered Raka, East, System 3, and MAS before settling. Initial results are good, but I cannot test like PS can! Thansk!

Posted by: PAUL S | September 1, 2011 1:12 PM    Report this comment

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