Find True North and set the direction of the Sunquest sundial

The Sunquest sundial should be oriented towards True North so that the axis of the gnomon is exactly parallel to the axis of the earth.  Find True North and set the direction of the Sunquest sundial after the latitude and longitude settings are finished.

truenorth01Setting via the North Star (instructions by Richard L. Schmoyer, 1983).

If the North Star, Polaris, is visible, direction and angular elevation can be set at night.  The entire sundial, except for the gnomon, is assembled and oriented through the empty gnomon pivot holes, aligning them upon the star.  The North Star is located after finding the Big Dipper, by following the line from the two stars forming the pouring end of the dipper.

With your eye at the southern or lower pivot hole, turn and tilt the sundial to bring the North Star into view through the upper pivot hole.  Now tighten the pedestal jaw bolt just a little to hold the setting for further refinement.  Meanwhile the two bolts holding the latitude and equatorial nested crescents should be tight.

Sighting accuracy is better if your eye is looking through the center of the lower or south-end pivot hole.  make a plug to fit the 1/2″ gnomon bearing hole, and with a 1/16″ sight hole; or tape a piece of cardboard temporarily over the bearing hole and make a small sight hole at the center.

Further, since the North Star is so-called only because it is the bright star near the true axis (extended) of the earth, the sundial should not be firmly tightened up until its axis also follows into space to true north, the point about which all the stars, including Polaris and the sun, appear to rotate.  Polaris is less than one degree from true north and its direction approximately opposite to the direction (from north) of Alkaid, which is the star at the handle end of the Big Dipper.

This pattern of Polaris, true north, and Alkaid, in whichever position it appears as it rotates in the sky according to the hour or season is used to position the sundial axis for the final alignment.

As viewed from the sight piece, the angular distance from the center to the edge of the north end bearing hole is approximately equal to the part of a degree that the star departs from true north.  It is an interesting exercise to find that the time-telling accuracy of the Sunquest sundial is sensitive to this small correction.

With your eye centered at the lower pivot hole, adjust further to make the upper hole center appear to move along an imaginary line between Polaris and Alkaid, toward Alkaid, but just enough to put Polaris almost out of sight at the edge of the hole.  Tightening the pedestal bolt now fixes the axis of the sundial.  This setting need not be disturbed in removing the two bolts holding the equatorial crescent and the latitude crescent halves together to re-insert the gnomon.