The MADAS calculator (PWJ220)

MADAS is a Swiss mechanical calculator brand from the H. W. Egli company in Zurich. It was made in the 1940s and it has some extra features other machines don't have. MADAS means Multiplication, Automatic Division, Addition and Subtraction.
(I bought it for $10)

[@sks220]

The engineering behind stuff like this is astounding. I'm a software engineer and I've made some cool things but nothing that hasn't been done before. The engineers behind this are on a whole different level.

[@no-one3795]

Mechanical machines like this always fascinates me

[@Jonas_Keunecke]

Wow, that was fun to see this machine working! Made it possible for me to imagine the noise in a room like the one shown in the movie. We have kind of a similar machine, a "Comptometer" from the US, that I never bothered to find out how it works. I should do that on the weekend, this video probably helps a bit already

[@PlaywithJunk]

You should visit this KZbinr kzbin.info He has multiple videos about various comptometers.

[@jimsvideos7201]

It is a perfectly usable tool and a remarkable feat of design.

[@Sven_Dongle]

I bet over that things lifespan it has performed at least several microseconds worth of calculations equivalent to a modern desktop computer!

[@PlaywithJunk]

FLOPY = FLoating point OPerations per Year...

[@f.k.b.16]

There is not much I'm scared to tare into. Even on things that I don't know a thing about... Except things like this! This is a terrifying mix of mechanical awesomeness and my worst enemy... Math!

[@PlaywithJunk]

A real super villain :-) It's always a funny moment when you remove a part and you hear "shpling..." and you realize that it will take half a day to find out how to get that shpling part back in place.

[@TheEmbeddedHobbyist]

Nice, reminds me of the teleprinters like the Creed 75. used one for digital modes on the Ham bands way too many years ago.

[@gvii]

I really can't blame you for not wanting to take it apart, even though I imagine it was pretty fiddly trying to clean that front panel. I absolutely love these mechanical calculators, but holy smokes, they are a nightmare of bits internally. I would be EXTREMELY hesitant to go poking around in one even if I had a complete service manual. But the amount of engineering going into that thing is a bit on the mind-boggling side, for sure. Very, very cool. As for the side panels, is it just straight paint? Or that crinkle paint you often see on older devices of the sort?

[@PlaywithJunk]

I think the crinkle look is original. It is everywhere evenly distributed. If it was a thing that came with time, there should be parts with more or less of the effect. I once removed the carriage assembly, that just unclips when you move a tiny lever. But to put it back in place took me one hour. Not because it was complicated but to find out the right position to start with. These machines are sometimes remarkably well accessible. But you always need to know some tricks.

[@gvii]

@@PlaywithJunk I do like that crinkle paint a lot on older items such as that. I always did wonder how that effect is achieved. Of course, I have yet to bother looking into it, lol.

[@PlaywithJunk]

@@gvii When I remember right, crinkle paint comes in two cans. It’s basically two types of paint that are not compatible and the second layer starts to crinkle. Normally this effect is not wanted, but in this application it’s exactly what does the trick. You have to practice until it looks good.

[@arzelaascoli9189]

What happens if you try to divide by 0?

[@Petertronic]

Amazing machine! Have you tried any kind of filtering to stop the clock interference?

[@PlaywithJunk]

No, not yet. But it seems to get better. I think when the brushes get cleaner while running, the sparkys will reduce. Also the odor of electrically burnt oil gets weaker 🙂

[@Petertronic]

Haha, I love that! Hopefully not as bad as RIFA capacitor smell (my house has smelled of that for two days)@@PlaywithJunk

[@PlaywithJunk]

@@Petertronic No, it's not the capacitor (if there is one...) It smells like some grease has creeped onto the rotor and that is now burnt away by the brushes. A typical smell of old electric machines...

[@bkahlerventer]

Nice video. A more accurate pi is by using the numbers 113355 in the formula: 355/113

[@PlaywithJunk]

That's a new one to me... but who needs an approximation when you have a PI button on your calculator ;-)

[@fritz46]

With 10 digits in the counter, you should use 103993 / 33102 for even more precision!

[@rewindoflow]

It's actually not too complicated to remove the entire keyboard - there is just one screw that screws into a linkage on the left, which is very easy to access, and then there are four screws on the top face in each corner and it should just lift free. I have managed to give mine a couple of scratches and scrape away some paint - do you have any idea how I could easily repair this? It doesn't have to be perfect but it would be nice if I could make it look a little nicer? And what do you use for the cleaning? Also, do you know the serial number - mine is 58500

[@PlaywithJunk]

The reason why I hesitate to remove the keyboard is that I already removed the carriage and it took me one hour to fiddle it back in place. It was not complicated but I needed to find out HOW it could be done correctly. Maybe I'll try it one day... For the scratched parts I would try to sand them down until the are smooth and then paint them with black crinkle paint. That's something similar as the original "leather" paint. Comes in spray cans and is easy to use (relatively).

[@haralamc]

So its basically an EMP grenade

[@PlaywithJunk]

Yes... and itself it's EMP safe! Works even without electricity.

[@Rob2]

It is not your clock that is running fast, it is your brain running slow due to the noise 🙂 Q: How many megaflops does it have? A: Yes

[@m.3041]

22/7 - last digit should be 3 , not 2 , that might explain why swiss banks earned so much money?

[@bernhardschuepbach4533]

😁

[@PlaywithJunk]

That's because they divide the Pi unevenly... they always take the bigger piece and you have to pay for the knive ;-)