New Larger Curved Analemma Plate with Tiltable Nodus for use with 3 Original Heliochronometer Sundial Designs

Summary

Just replace your original flat or curved plate vertical analemma arm with this larger curved model and add a tilt capability to your Nodus.  Please note that this design is only compatible with northern-hemisphere heliochronometers.  If you are interested in a southern-hemisphere design, please refer to this Printable to download the additional parts:  Larger Curved Analemma Plate Design for Southern Hemisphere Heliochronometers by 3DMason | Download free STL model | Printables.com

Main Features

• 25% Larger Curved Analemma Plate for improved reading accuracy;

• A Tilt Adjustable Nodus with curved vertical arm for Sun Elevation Compensation throughout the year. These modifications enable a sharper shadow to be cast against the Analemma plate, especially at the elevation extremes;

How was it Designed?

For definitions on the various parts that make up a heliochronometer sundial, see my other Printable at:  Heliochronometer - World's Most Accurate Sundial by yba2cuo3 | Download free STL model | Printables.com

The spacing between the Nodus & Analemma vertical arms was increased to 100mm; 20mm greater than my original 80mm design.  The spacing increase results in a 25% dimensional increase of the Analemma Curve, therefore increasing the overall reading resolution by an equal amount

The larger Analemma curve was calculated & designed using the instructions from one of my Printables which utilizes several Python scripts within Blender.  Check out How a Curved Analemma Plate was Designed into this Heliochronometer from:  Curved Analemma Plate for a Heliochronometer Sundial by yba2cuo3 | Download free STL model | Printables.com

The Nodus was modified to add a tilt feature & the original flat vertical arm was converted to a curved design.  As a result, the Nodus projection can now be optimized to match the sun's height above the horizon during the course of the year.  This results in a sharper sun spot casted against the Analemma plate which also helps with the reading resolution.

The mounting locations for the vertical arms on the original Alidade remains unchanged from my original heliochronometer designs which means that the larger curved plate Nodus & Analemma designs presented here can be also used on my other heliochronometer designs without additional modifications i.e. 

1. Heliochronometer - World's Most Accurate Sundial by yba2cuo3 | Download free STL model | Printables.com
2. Heliochronometer (version 2) - World's Most Accurate Sundial by yba2cuo3 | Download free STL model | Printables.com
3. Gard Heliochronometer Sundial Derivative by yba2cuo3 | Download free STL model | Printables.com

Understanding how to design an analemma is crucial for the successful construction and accurate workings of a heliochronometer sundial.

If you don't already have a heliochronometer and want to download a design, or you would like to get additional information on heliochronometers in general; i.e. history, theory of operation, design, how to align and use, etc.  refer to this useful Printable:  Heliochronometer - World's Most Accurate Sundial by yba2cuo3 | Download free STL model | Printables.com

Print Settings

• Printer brand:  Prusa
• Model:  MK4S
• Supports:  Yes
• Resolution:  0.15mm
• Infill:  20%
• Brim: Yes - 10mm
• Filament brand:  Doesn't matter
• Filament material:  ABS
• Filament color:  Doesn't matter
• Special Notes:  
  • Print in an enclosure for best results. 

Nodus Assembly

1. Screw a M2x14mm screw all the way into each Nodus tilt knob;
2. Place the Nodus into the oval opening of the vertical Nodus arm such that the Nodus cone is pointing outwards as shown below;

1. Push each knob into the holes located on the sides of the arm & align them with the Nodus mounting holes .  Screw the knobs all the way in but allowing the Nodus to turn freely using the tilt knobs;
2. Remove the Alidade assembly from your sundial by removing the center retention screw & nut from the main dial plate. Using the same M4x16mm screws from your original vertical arms, install the new Nodus & Analemma vertical arms onto the Alidade.  Note the positions in the photo below.  The Nodus arm should be curving inside the main dial, with the Nodus cone pointing outside & the arm mounted on the opposite end of the Alidade arrow.  The Analemma curved plate with the text should be pointing inside the main dial also & mounted on the side with the Alidade arrow.
3. Replace the Alidade onto the main dial plate using the original hardware.

Your sundial upgrade is now ready for use!  I would recommend to re-align & re-level your sundial base since things might have moved.

If you want to try a planetary geared sundial/clock hybrid design which simplifies reading minutes without the use of a secondary Vernier scale, see:  Planetary Geared Sundial/Clock Hybrid - The Best of both World's with Reading Accuracy Optimization by yba2cuo3 | Download free STL model | Printables.com

If you think this is a cool design, don't forget to hit the like button. I hope you enjoy building this design & thanks for your support!

References:

1. Sundials - Their Construction & Use, R. Newton Mayall & Margaret Mayall, Dover Publications Inc., 1994
2. The Equation of Time:  The Equation of Time
3. Heliochronometer - World's Most Accurate Sundial by yba2cuo3 | Download free STL model | Printables.com
4. Heliochronometer (version 2) - World's Most Accurate Sundial by yba2cuo3 | Download free STL model | Printables.com
5. Gard Heliochronometer Sundial Derivative by yba2cuo3 | Download free STL model | Printables.com

Larger Analemma Plate with a Tilt Adjustable Nodus.