The amazing world of Casio watchmodding

Ten years old and still ticking. On its third band.


I had no idea Casio was still a thing. These watches are sweet and the prices are wow good. This one is $10 and looks perfect.,420_QL65&keywords=casio+watch+women#immersive-view_1492224532148

I’m very curious about the databank model and wonder if there is a way to get a com port modded. Seems like the data is there and there is an input and output (screen) so must be a way.

Edited to add…pricey but this really is a pretty smart watch

I still like the dang calculator in these Data Banks. :frowning:


@ChickieD, I have the men’s version (larger diameter) of that MQ24. In fact, I have a few of them. One died and a new battery didn’t help, on the others the cheap bands broke and a replacement band was more expensive than a new watch. They’re a bargain for the price, and look as good in person as in the photos, but if you buy one don’t get too emotionally attached to it.

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Can th F-91W display time in 24 hour format?

Yes, the the right bottom button is used for switching between 24-hour format and 12-hour with am/pm notation. If you look closely at the photo’s in this thread you can even see the text pointing to the button indicate this :smiley:

I think this button is also my greatest complaint about this watch, it’s really easy to press this button accidentally, I prefer keeping it in 24-hour mode but through normal wrist motion throughout the day I often end up switching modes without wanting to.

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That is awesome! This will go in my “gotta do this sometime” brain bucket for percolating.

First comes the extremely tough decision on what oil to use and then the even tougher decision on which watch to open up first… And then last, will I ever need a watch that can withstand depths like this?

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Is that the button’s only function? Seems odd to dedicate a button to something that would typically just be used when setting time.

Just add an option when setting AM\PM\24

Which is a fair opinion to have. I never cared for the version with the calculator but you know… personal opinions and whatnot :slight_smile:

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BTW some of these Casio hacks aren’t wonderful things :frowning:


Darn, that’s a dealbreaker.

Personally, my goto is the the CA53W.

I originally got it for a backpacking trip.

It’s got an alarm - great in a hostel since you may not want to leave your phone unattended while you sleep. 2 times zones, so you don’t accidentally wake up your friends texting your afternoon tea in Tokyo. And the calculator for calculating exchange rates / splitting bills.

No, it’s alsof used in the sub screens, to change the alarm time and start/stop the stopwatch.

The button layout and the extra functions really work very well and the placement and functions are very well thought out. I think this function was just kinda left over, and placed on the single remaining free spot ¯ \_(ツ)_/¯

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Is it a 5? Those things are unbelievably cheap for a fully mechanical watch. And reasonable quality too, although I’ve heard the older ones made in Japan are more so than the newer ones made in Malaysia.

I got it on Amazon. Looks like the exact one isn’t available anymore. But they have a lot of varying qualities. I’ve got a whole collection of the NATO style bands to help fulfill my Bond fantasies.

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My chubby Italian hand is always hitting that 24 hour button. No real complaint though. A bit more annoying when it sets the alarm, though. :sweat_smile:

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Thanks for the 411. I’m exploring all their options. I really dig their aesthetic - really functional. My big thing is that the numbers all have to be easy to read. Shocking how few watches live up to that standard.

36 posts on a digital watch thread and no Douglas Adams?!

I weep for our future.

It shan’t be 37:

Far out in the uncharted backwaters of the unfashionable end of the western spiral arm of the Galaxy lies a small unregarded yellow sun. Orbiting this at a distance of roughly ninety-two million miles is an utterly insignificant little blue green planet whose ape-descended life forms are so amazingly primitive that they still think digital watches are a pretty neat idea.


Yes, a 5. It was not only cheap but good-looking, and works really well, requiring practically no motion at all to keep it wound. It isn’t quite as accurate as mechanicals costing many times the price (or quartz watches costing the same or less!), but I don’t use it to time lab experiments. The band it came with is terrible (the leather trim started rotting almost immediately), and the chunky loops on @ddmone’s band would match the 5 very well.

I just want a band that looks vaguely stock on an F-91W and fits a 9 inch wrist.

If you go out in the morning and there isn’t a puddle of oil under your Norton, don’t start it, because you’re out of oil. :wink: