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~ click on a small picture for further details ~
The V-shaped sundial requires some mechanical skill for building. The version shown here required a little brazing and careful wire bending. The feature is that there are no shadows that obscure or confuse the basic time function.

   As in the other designs, this one is centered on 2pm for daylight savings time (1pm standard) to give 8am to 8pm in the summer, but you can set the scale to whatever 12 hour time span you like.

    Some variations of this design are possible, but be careful to consider the resulting shadows for all times of year and throughout the day. This design allows for easy setting of two of the three axes. By going out on a clear night, simply sighting along the time gnomon to the north star, sets the elevation and the direction. If positioned correctly, only the time will have to be set the next day, the date should be correct throughout the day. If not, see the section dealing with the Pivot. The date ring radius was chosen to be one half of the time gnomon. Again, any radius could have been chosen, but this gives a reasonable plot size and looks attractive. As discussed in the "Analemma Plotting" link, there is no relation between this radius and the time scale lengths.
   These two wires were again brazed in place, but it is possible that adaquate strength might be achieved by drilling a hole and using epoxy. In some ways this would be easier to align since the middle section of the wire could be cut off afterwards. The one side has to be quite strong, however, since it provides the support. The version here was done by carefully measuring the distance from the center of the date shadow wire to this wire circle and clamping before brazing.
    For the summer, the time shown here is about 12:25pm since it would be daylight savings time. Having the dual scale avoids readjustment when the time is changed. The date shadow wire is adjusted during the year so that its shadow is aligned with the analemma plot on the glass. There is a paralax problem here if the wire is too fat, but this is not really a problem if one looks at the shadow with the sun at one's back while making the date adjustment.
   The glass date platen was made by plotting the analemma on inkjet overhead transparency film. The printing is applied to the rough side. (See the link on the bottom right side.) The glass was coated with a clear epoxy, the plastic film with the plot was then smoothed on top, and a second coat of epoxy was then applied to the plastic film. This provides a tough weatherproof surface that resists scratching and also keeps the V structure from slipping in the wind. For added looks and enhancement of the plot, the months and plot line were highlighted with a decorative ballpoint pen. It is a good idea to test the ink to see that it doesn't run with the epoxy. To avoid problems, a clear acrylic spray can be used over the ink.
   Notice that the 15th of the month is plotted, but the 14th and 16th are not. This is to make the 15th is more visible. Within a couple days, the date can be read right off the analemma plot. The V scale is bent to 60 degrees and has a length such that the center of the gnomon time wire is exactly in line with the top ends of the V. This gives exactly 12 hours of usable time, without obstruction, even near an equinox. Again, it can be seen that the right side dangles while the left side provides the correct angular support. It can be seen that the tilt of the V is between flat when all the way to the right, and 15 degrees when all the way to left. A 15 degree tilt represents an hour of time adjustment. [(15deg/hour)x24hours=360deg, a full day.] This scale is almost linear, as shown in the equations in the "VDial Theory" link on the bottom right. Within a few seconds, the 16+14=30minute analemma width can be simply set equal to the radius from the date shadow wire to the date wire arc.
   The most critical detail is the time scale. A good approach is to tape some paper together and draw a half circle with the time gnomon wire atthe exact center and a straight line between the tips of the V scale. A drawing compass set equal to this radius will mark off 60 degrees on the circumference. Marking off arcs above and below the circle from adjacent marks will and drawing a line from the circle center will split thisinto 30 degrees. Cutting the angle in half to 15, then 7.5 degrees will give the hour and half hour positions. Laying the V structure in top of this plot, maybe with a small notch for the time gnomon wire, will allow the time scale to be marked on the INSIDE surface of the V time scale. The scale will be spaced wider at the vertex than near the middle. It begins to spread out again toward the tips. Care is important. If the time is off by more than 4 minutes, in the summer, this exceeds the error being corrected. The glass platen is epoxy coated to make it esentially transparent to avoid a shadow. An opaque surface would lead to confusing shadows, which this design has eliminated. It is also desirable to have the plot line and months a darker color to avoid the same problem, although black may be difficult to see against the background.
   It is imperative to have a solid support structure, like this stump. Remember, the time should be correct after wind, rain, drought, and freezing weather. It is much more fun to watch the months go by accurately without having to constantly make adjustments. Looking at the platen bottom, it is easy to see where the glass has been glued to the + shaped wire support. The two wires were brazed together here, but they probably could have been simply glued. There is a fair amount of stress on the shorter wire to keep the V from tipping. As an alternative, the long wire could have been looped back into a U or circular shape and glued.
   Notice that the short wire must be short enough to miss the shadow wire when it is adjusted. Looking at the front, it is apparent that only the left wire circle segment gives support. There are two stops on the left wire. These are to avoid having the date shadow wire slip beyond the edge of the glass platen. The support pipe is shown brazed to the right side, but it doesn't matter since the pipe will be bent, or the couplers adjusted, to set the time.
   The length of the gnomon wire should be about equal to the vertical wire length. The earth tilts at 23.4334 degrees which means that each side of the gnomon wire will have to be about half the height or more for the projected shadow to fall on the time scale at the vertex. It is a good idea to curl or cap the ends of the wire to prevent possible injury. This vertex picture shows the details of the basic structure. The vertical support wire passes through the scale to a perpendicular wire that displays the date shadow. This date shadow wire is hooked around the glass analemma scale to keep the V structure from tipping back and forth. Since the structure always tilts, except at the equator, some free play is acceptable to allow free movement for setting the date. On the other hand, it should not be allowed to wobble in the wind.
   The critical construction detail is that the date shadow wire must be the center of the two outside wire circle segments. The curvature of the scale where the vertical wire passes through is of no importance, as long as it is above the date shadow wire. Any variations are taken care of when the time scale is drawn. It could easily have been a more U shape instead to the V. It is good to have the sides straight, however. This way the the shadows that the V casts do not cause confusion. After some length of time, the paint on the analemma fades and the overcoating tends to fog. A more weather resistant method is shown which only uses a wire the shape of the analemma, and markers on the wire. The first of each month is marked. Also the Summer and Winter solstice are marked with a more obvious soldered-on wire loop.
   The seasons are marked on the outside frame by paint with Winter-blue, Spring-green, Summer-red, and Autumn-yellow. Of course markings could have been made into the metal directly for more durability.
   Notice that the thinner wire analemma is below the level of the guide frame wire so that it never touches the slide.
   On the whole, this seems a simpler and more rugged method to use.