NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Metal 3-Arm Protractor "Handedness" (Station Pointer)
From: Fred Hebard
Date: 2025 Sep 3, 08:07 -0400
From: Fred Hebard
Date: 2025 Sep 3, 08:07 -0400
I wonder whether some 3-arm protractors had a scale running from 0 to 360 degrees rather than two from 0 to 180. Then the left or right handedness would refer to whether the scale ran clockwise or counter clockwise?
Fred Hebard
mbiew@comcast.net
On Sep 2, 2025, at 17:20, NavList Community <NavList@navlist.net> wrote:Re: Metal 3-Arm Protractor "Handedness" (Station Pointer)
From: Alexandre Eremenko
Date: 2025 Sep 2, 12:38 -0700Can you give any links where some particular protractor is called "left-handed" or "right handed"? Perhaps with a picture?I own one of them, and have seen many pictures, and I did not spot any difference (they all look remarkably similar, independently of the country of production).
The thing looks completely symmetric and a mirror image will look exactly the same, including the scale, except a very small difference in position of the central arm. I cannot imagine what difference this small deviation from symmetry could make.
Here are two photos of my protractor:
Alex.
