Each pose is 10 to 15 minutes.


In this case, times are different angles from one side to the other, with reference to the line representing the 12 noon, ie, graduation is not symmetrical and this very important detail must be taken into account if we are projecting a vertical clock for a house facade. Similarly, depending on the value of the decline of the dial with respect to the North or South, only you can view the hours or from dawn to noon or from noon until sunset.
design Quadrant sundial declining presented in this post is designed to simulate the corner of a house, ie two adjacent walls and kept at 90 degrees relative to each other through the foot or gnomon. This concept is to achieve structural stability of the clock and ensures that the two walls that are kept up to 90 º. Quadrant angle to our project declínate Solar is 45 ° to the vertical plane that looks at the poles.
performing the necessary calculations to determine the quadrant angles downward schedules can make tracing them on paper to get this way the templates.
templates glued to a cardboard cut out. Assembly
the clock keeps the same look like this.
Note in the pictures held by the gnomon angle with respect to quadrants (in this case 45 degrees) and how are the quadrants corner for stability.
To read the time on this watch, we must orient so that the gnomon is aligned with the axis of the poles, ie pointing to them in the same way we did with previous clocks.
dial clock dial downward and horizontal.
Clock equatorial sun dial and the watch dial downward.
This last image shows clearly the deflection angle of the sundial has declining compared to the equatorial sundial.
Made the path, we have the pattern for making the sun clock
Cut the pieces and assembled the watch, it keeps the look shown in the figures below.
Note in the picture the triangular shape of the gnomon, the inclination of the upper edge of the triangle with respect to the horizontal is just the angle that corresponds to the latitude of the place, so that once placed our sundial in a sunny spot, the top edge of the gnomon is parallel to the axis of the poles and pointing north. The time is marked by the shadow that is projected onto the horizontal dial.
horizontal dial clock dial with the vertical.
The watch dial vertical is more complex in design than dial equator, because the divisions indicating the time does not correspond to the simple division angle equal parts of 15 degrees of tilt per hour, but a graduated scale distorted by the vertical projection of the quadrant equator. However, for this instrument is functional, the gnomon must be parallel to the axis of the world, pointing to the poles in the same manner as the sundial equatorial dial.
With our knowledge of geometry and trigonometry in high school we acquired the ability to design and projecting a dial sundial vertical, horizontal and declining among others, once assimilated the idea of \u200b\u200bthe equatorial quadrant projections on other surfaces.
The following image shows the mathematical development to determine the projection of the equatorial quadrant hour angles on the vertical quadrant.
Templates cut and pasted to the cardboard base.
Cutting
binding groove of the foot to support gnomon.
union slots completed.
Quadrant front or north side.
Quadrant
rear or southern side.
Front View.
Note in side view the sundial is completely vertical, but the upper surface of the foot, which is the gnomon is tilted. The angle of inclination with respect to the horizontal have the same value as the latitude.
To view the local solar time, we must put our clock in a sunny spot and oriented in the same way as previous clocks, ie, the gnomon must point to the poles and parallel to them.