StreamZones.com         Longitude and Latitude Calculator       Horizontal Sundial       Vertical Sundial

This is a 20 second video of an amazing Digital Sundial.

It was produced using a 3D printer by a frenchman.

Sundials and Kangaroos

There is a tiny subtlety if you want to use this sundial in the Southern hemisphere:

Try to visualize an kangaroo in Australia. Just like everyone else, this ‘roo has to orient the tip of its sundial toward the north pole. For him, that means having the tip of the sundial pointing toward the ground…. this doesn’t seem very practical. Our hinge mechanism doesn’t even allow to tilt the sundial below horizontal.

The trick here is simply to build a subtly different magical black box (also called a gnomon) for kangaroos: in the Openscad script you can set a flag that will simply rotate upside-down the whole swiss cheese inside the gnomon, and build a ‘Southern-hemisphere’ version of the gnomon. 

This way, the ‘roo can simply use this Southern-hemisphere sundial exactly the same way a cow or a penguin would use their Northern-hermisphere version the sundial, with just one difference: the ‘roo will have to point the tip of his sundial toward the *South* Pole. 

Fun fact about this sundial

You will most likely never see it in a supermarket or a department store. The swiss cheese inside the sundial is so intricate, that you can’t realistically use injection molding, or some other mass-production method. 3D printing seems actually to be the only practical way to build this digital sundial ! 

Open Source model

Click this link to download the source code for a 3D printer.

Here, this digital sundial is an interestingly exotic case:

It seems almost perfectly well-suited for an Open Source Hardware business model. You can only craft it with hobby/prototyping tools, and only very slowly (one every 1.5 days): basically it’s ideal for ” High-Tech Artisans “.

Makers with a 3D printer will need  patience for 35 hours of printing (it is a somewhat challenging print) still will have the opportunity to build their own digital sundial, and then hack it / modify it / invent something else.  Geeks that might be interested in a cool gadget that won’t be available anywhere else.

Wouldn’t you also need also to adjust the angel based of the time of year? I mean the sund doesn’t get up so high in the winter.

That is a brilliant question !! And I am glad you asked. Indeed the declination of the sun changes by as much as 47′ during the year: the sun will move along the longitude lines from one day to the next.

The “trick” to get the sundial to work throughout the year is really trivial actually: you just need to use very wide pixels (along the north-south direction). It’s a bit like seeing the sun from the bottom of a well: the wider the well, the longer you will see the sun at the bottom.

So ideally, a pixel should be wide enough to accept sun rays tilted (along the north-south axis) by as much as 47′.
In pratice a compromise is needed with the 3D printed version: to keep it printable, Limit that angle to about 24′. So to use this 3D printed sundial throughout the year, you need to slightly misalign that sundial up or down by about 10′ every 6 months.

Would it be feasible to increase the time resolution to 10 or 5 minutes?

It should be possible indeed  with a  a little bit of fiddling with the Openscad script.
But you might have either to print tinier details to get it to work properly, or alternatively to print it bigger (with the same resolution). Note that you can always print the gnomon in several pieces if it becomes too big for your printing plate.

FineTunedUniverse.com

GooToYou.com

ICR.org

Creation.com

CreationMoments.com

AnswersInGenesis.org

North West Creration Network

ICR.org   Defenders Study Bible

John 3:16

3:16 For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.