~ click on a small picture for further details ~
The positioning must be done in a way that maintains the correct setting throughout the year, not just the day that it is set.
    It may be done simply by bending the support pipe, or easier, by rotating pipe couplers. Three versions are shown on their stumps. The CDials and VDial are all using the bent pipe method. All end up pointing the same direction when correctly set. With just the bent pipe, it is necessary to grip the pipe firmly and bend the same as if there were couplers. This will require several sucessively better attempts over several days to zero in on the exact position. With the ODial or CDials, it is probably easier to make one of the adjustments in the morning and/or evening and the other adjustment at a time 6 hours between.
    It is also possible to align the elevation and direction on a clear night. The time wire should align with the north star. A compass during the day can also be useful, but remember, it is off several degrees in many locations. The elevation can be also set with a level and protractor set to the local longitude. In the end, if the sundial is well constructed, the date will always be correct as well as the time. Using pipe couplers allows almost independent adjustment of the elevation, direction, and time. All the couplers form 90 degree angles to each other. The couplers are shown here for the VDial. The bottom two are 6 hours apart, as must always be the case, to keep these two adjustments orthogonal (independent.) The adjustment for the VDial must be made near 10am in the winter (11am summer) then the other rotated near 4pm winter (5pm summer) because this is the time when the date wire shadow is visible. The idea is to have the axis of rotation be around the line between the sun and the sundial. The only times this works out exactly are on the spring and fall equinox when the path of the sun is in the plane of the sundial time scale. The setting may have to be refined over a couple days. The coupler is rotated so that the date wire shadow projects a shadow on the correct date on the date plot.
    The bottom two couplers are marked with the time they should be set, while the top coupler, marked T, can be set for the correct local time whenever it is convernient. Overall view shows how the couplers look on the VDial. The compression nuts can be loosened and tightened to allow the rotation of the pipes. A 90 degree coupler could have been used, but this is less confusing for a demonstration model. It is also cheaper to just bend a piece of pipe. The closeup view shows the 90 degree bend between the two upper couplers. The order of the couplers is arbitrary as long as they are accurately in the three planes.