![Casio Metcon CM-32 [458]](https://www.liquidcrystal.co.nz/wp-content/uploads/2019/08/cm32.jpg)
Metric to imperial conversion was not as easy in the 1980s as it is today.
Today you can just open a web browser and enter a plain english statement like “convert 37.4 celsius to fahrenheit” and Google will helpfully give you the answer in a fraction of a second. It also tells you the formula is (celsius x9/5) + 32. In the 80s you’d have to remember that formula, or look it up. And if you wanted to convert it the other way, you’d have to remember the formula is (Fahrenheit − 32) × 5/9.
Enter Casio’s Metcon calculator in 1985 — the CM-32 (and CM-321 in a metal case).
A couple of years before this, you could buy a desktop calculator that would do conversions for you, but this was the first that did so in a wristwatch.
To use it, you’d enter calculator mode and enter your number to be converted. Then press the recessed side button once or twice (depending which way you wanted to do the conversion) and select the key with the conversion you want.
Feet to metres, miles to kilometres, temperature and more; this calculator watch did it quickly and easily.
While it didn’t come with a game, this calculator watch was probably more useful to the 1980s student than the similar-looking CA-51.
I don’t know how many of these Casio produced, but they are rare these days and have never been seen in great numbers.
The QW458 module can only be found in the two CM-xx watches although Casio have produced several metric converter calculators over the years, one of the earliest being the MC-800 which would have pre-dated the CM-32.
While it’s a bit of a one-trick pony, it’s a great trick the CM-32 offers and is one of the best of Casio’s mid-late 80s calculator watches. Prices can vary – you can get one for a bargain if you keep a close eye on eBay, but can also sell for several hundred dollars in excellent condition.
I got this one in nice condition, but missing the strap. A generic strap just won’t cut it on a Casio of this era (or any Casio, really) and I was lucky to find an original replacement. Original straps are often harder to find than the watches themselves, and are expensive for what they are, but are worth every penny in my opinion.
Thanks for this great article! I have recently gotten into collecting 80s Casio calc watches (as a child of the 1980s, I love these). I have around 30 odd different models in my collection so far, and I have both this one and the silver-cased CM-321 equivalent.
I can tell you that I still find use for these today (even if it is still a slight novelty use) – I’m an aerospace engineer in Australia and I work with a lot of US based aircraft design documentation (which is all in imperial). I also work with a lot of folks who have grown up with metric and can’t always get a ‘feel’ for how many kilograms a certain poundage of weight is, or how many metres or centimetres are in a certain distance of feet or inches. So I find myself occasionally ‘dazzling’ my co-workers with this amazing piece of 1980s tech to do the conversion without second thought, or without the aid of a more contemporary device.
The way this module does conversions only took a small amount of time to work out without the manual, and really is quite simple. I agree that this is one of those quirky little watches with a specific ‘special feature’, but I still think it’s pretty darned cool, and it still has some dazzle power (for a select group, at least!).
Keep up the great work!
Brad C
Its a lovely piece, I would be interested to know where you obtained an original replacement strap – I have not been able to source these anywhere! (The one you have looks to be the same that was found on the CA-50)
Hi Andy – you’re right; the strap is the same as the CA-50/CA-60.
Do you happen to have the manual for this? I also have a working CM-32 but I’m not sure if I’m aware of all the features.