NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: The new guy on the horizon...
From: Geoffrey Kolbe
Date: 2011 Oct 11, 07:34 +0100
From: Geoffrey Kolbe
Date: 2011 Oct 11, 07:34 +0100
At 20:54 10/10/2011, Randall wrote:
The method of levelling the AH is the set the level on the AH in line with (or parallel to a line connecting) two of the adjusting screws. Adjust these screws (and only these screws) so that the level reads "zero" and the AH is level in that plane. It is usual practice to turn both these screws at the same time and at the same rate, but in opposite directions. Turn the level through 90 degrees. Adjust the third screw (and only that screw) to bring the level to zero.
Repeat the above a few times until the level reads zero in any orientation.
I have a head lamp which has LEDs in it. I removed the white LEDs and put red LEDs in their place. I can use this light to set up instrumentation at night, write down readings and generally fiddle about without ruining my night vision. Head lamps are available with red LEDs, I think, but in any case a red flashlight (or torch, as we say in the UK) is useful in such circumstances.
Geoffrey Kolbe
I level each of the three legs at least twice, reversing the level by 180 degrees at each leg to get the most accuracy. The wing-nut head screws have ¼-20 threads with a 90 degree, (1/4) rotation giving 1/10 degree change. When I rotate the level 180 degrees it takes about 1/8 turn to get back to zero. The digital level is easier to see in the dark compared to the standard torpedo spirit levels I started with. No flashlight required.
The method of levelling the AH is the set the level on the AH in line with (or parallel to a line connecting) two of the adjusting screws. Adjust these screws (and only these screws) so that the level reads "zero" and the AH is level in that plane. It is usual practice to turn both these screws at the same time and at the same rate, but in opposite directions. Turn the level through 90 degrees. Adjust the third screw (and only that screw) to bring the level to zero.
Repeat the above a few times until the level reads zero in any orientation.
I have a head lamp which has LEDs in it. I removed the white LEDs and put red LEDs in their place. I can use this light to set up instrumentation at night, write down readings and generally fiddle about without ruining my night vision. Head lamps are available with red LEDs, I think, but in any case a red flashlight (or torch, as we say in the UK) is useful in such circumstances.
Geoffrey Kolbe
