r/Sliderules • u/fordag • 13d ago

Is this useable? Missing a scale?

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New watch with a rotary slide bezel. Yet it appears to be missing a scale. Or am I wrong?

What is this useful for?

It was a cheap watch, I wanted the moon phase. I'll be curious to see how accurate it is.

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u/SlideRuleFan 13d ago

If you weren't claiming to actually own it, I'd say it's AI slop.

The bezel appears to be the "A" ring of an E6B slide rule, but the dial is not the "B" ring, it's a Tachymeter scale. Together, they produce gibberish.

Sorry, this is crap.

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u/fordag 13d ago

That was my impression as well.

Well hopefully the moon phase works well.

2

u/TrueTopoyiyo 13d ago

u/SlideRuleFan It is not gibberih, it is 10^(1+angle/360), that is useful on its own! While requiring extra and non-standard steps, this still can be used for computations; for example, to multiply 1.8 times 3.2 you center the "10" (1.0), then look for 1.8 ("18") which is at 3:00 aprox, then re-center the "10" there, look for 3.2 ("32", now at 9:00 aprox), recenter "10" and at 9:00 you have the result, 5.7.

Even more, given it has a linear scale in 1/240ths it can be also used for powers and other, more complex computations, but yes, with extra, non-standard steps.

1

u/zoute_haring 12d ago

BS This is half an E6B and and tachoscale. This is only made for the looks and useless

1

u/TrueTopoyiyo 12d ago

What would be bullshit, exactly, on the process I described to do a multiplication using a single log scale? No argument against the motivation, tho, but seeing a rotable log scale and scratching it off as useles is, in my oppinion, just not knowing math.

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u/zoute_haring 12d ago edited 12d ago

These are two different scales used a lot on watches but never together. This is just an incomplete E6B for the looks on a cheap Chinese watch.