Schedule wheel - photo and video

**Altair** · Dec 18, 2023, 10:51 PM

Schedule wheel.

2:59 video:

Previously:

Gravity flow hydraulics calculator - photo
Decidial British currency converter - photo
Napier's bones calculating device - GIF

**Bony** · Dec 19, 2023, 10:58 PM

A handy gadget, but if you seldom need to work out dates and days here's a suggestion how to easily do this for free by simply using a spreadsheet.

Use the format function in a cell to show the date format you prefer and add or subtract the number of days in question. The resulting date will show your answer.

**Toolmaker51** · Dec 20, 2023, 06:24 AM

The cardboard date 'tool' is likely a 'Perrygraf'. That company designs and manufacturing produced a wide array of such slide rules for a large variety of industries and applications. As such, they are not only handy and dependable for estimating, there's a brisk trade among collectors.
I'm afraid many wind up mere fidget toys in some twits mancave.

**mklotz** · Dec 20, 2023, 09:57 AM

Even easier than a spreadsheet, go here...

https://www.timeanddate.com/date/duration.html

and click on the "Calculators" tab and you'll find a selection of date calculators including, among others, date-to-date and-date arithmetic.

**Bony** · Dec 20, 2023, 04:33 PM

Well spotted Marv. Interesting that the date format shown on that app is dd/mm/yy which is the most preferred way down under. I'm always impressed by the enormous variety of useful (& useless) apps that have been developed. I have about 80 on my phone alone.

**mklotz** · Dec 20, 2023, 04:53 PM

Originally Posted by Bony

Well spotted Marv. Interesting that the date format shown on that app is dd/mm/yy which is the most preferred way down under. ...

When I worked in Europe, I naturally picked up the d/m/y notation. However, we had other Americans working with us so, to forestall confusion, I took to writing the date with the month spelled out - 20 December 2023. To this day I still date checks and things that way so nobody will be confused.

On the other hand, if you have dated files/pictures on your computer, naming them with the date in the form yy-mm-dd will automatically arrange them in chronological order when viewing the folder in which they reside.