I am working on a watch face with a tourbillon hour hand and a large retrograde minute hand. I am using the expression (490 + (#DWFMS#/ 360 * 260)) and it works fine for 0 - 30 minutes, but then goes wrong.
You can do it with two hands hiding the one that has gone off track . You can use a non liner formula involving sin and rad or you can look at a +/- formula and use abs in it . I will have a look after Dinner . That particular hand is not best for stretching as it will change shape.
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This is a very crude solution following on from your Liner Concept . I found the scale you have a bit misleading . Going from 0 to 55 . Well if you wanted to run it in 5 minute steps that would be fine .
I will have a look at a non liner but someone might get there before me .
BTW I used the Minute hand for this test .
The curve looks elliptic, so using the the formula for an elliptical path, the formula for the height would be (used seconds for easy simulation, you can change to minutes):
(468/(sqrt(1-0.36*sin(rad(#DWFSS#/2)))))
I am assuming 220 degrees path as opposed to @russellcresser - makes it a little easier with the formulas.
So the rotation is: (220-(((#DWFSS#)/(360/80))))
The Hand details (using the standard one in your diagram):
X: 160
Y: 17
Width: (146/(sqrt(1-0.36*sin(rad(#DWFSS#/2)))))
This width makes the hand look proportionate all the time, although it only varies between 146 and 182.
Looking forward to checking that out Tom . When I am simulating angles I use #DWFHS# . Then I can use the time machine slider . I some times use it for positions stuff as well and Write the numbers down for later .
I’ve just been making my hour and minute retrograde scales portions of circles. As an example:
Changing the hand length is an interesting option. Somebody must have a hand that spirals outward for some purpose. I know I’ve seen spiral scales for some sort of purpose. Looks like tachymeter or just hours and minutes depending on the watch.
I have a few . My Maths is not strong I have to split the problem up . However We will soon have some of the masters show up and do it in one line . You must be a little more specific . I am not sure exactly what you want to do .
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I have a few . My Maths is not strong I have to split the problem up . However We will soon have some of the masters show up and do it in one line . You must be a little more specific . I am not sure exactly what you want to do .
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Thought you would be for the win on this one. I remember the back and forth on some of the formula as I tried to keep up without trying it personally (the only real way to ingrain).
To note is that my version of the Facer hands have the same width and height, so the formula will be the same for the width and height, making it easier.
Here my work in progress of this idea (inspection open):
If you are used to your hands in a certain format it is difficult to change , all your formulas are nonsense . I work like that as that is how resources come from my CAD . I use the same workspace for Dials and Hands .