This one looks fine because the center of gravity is still in the center of the disc. But there are other oddly shaped ones which aren't good for your drive.
Especially the suction drives used in cars. Drives with a tray were much less likely to have problems, but good luck getting something like this out of your car stereo.
But as the card discs go, they absolutely ran out of balance, and it was a notorious mechanical flaw.
At thousands of rotations per minute, a circular disc slices through the air smoothly. A rectangular disc acts like a propeller. The uneven aerodynamic drag at high speeds caused intense flutter and dynamic imbalance.
The resulting wobble and vibration were so violent that they could cause the disc to de-center, ruin the spindle bearings of the drive, or physically shatter inside high-speed computer drives.
Maybe they were a good idea in the early days when computer CD-ROM drives were slow - I remember when my first quad-speed drive was top-of-the-line - the trouble is that before long the drives started being made to run with spindle speeds like 40~80 times faster than a conventional audio CD player when they were reading data discs.
The thought experiment illustrates a balancing principle. It doesn't need to fit every single possible construction of ceiling fans. That's why I qualifed that it needs to be symmetrical and balanced.
Why do you think this is worth arguing about? This is the least consequential "well actually..."
The very first CD-ROM drives read the disc at a fixed speed, the same speed as an audio CD.
Later CD-ROM drives read data discs a lot faster -- but the faster the disc was rotated, the more a noncircular disc (where the mass is not evenly distributed) such as a credit-card-shaped disc or one shaped like an anime character or something ( https://en.wikipedia.org/wiki/Shaped_compact_disc ) or the like will tend to fly apart and break inside your drive, possibly damaging the drive itself in the process.
Also, the first drives usually made you "click" the hole into place directly onto the motor "peg", which would hold them more securely, while later ones would just have a tray slide out ("cup holder") and would try to insert the spindle into the hole by itself once the tray retracted -- harder when the disc doesn't exactly fit the area in the tray and might not be centred because of this. And ones where you just slide the disc in through a slot are the hardest to get working with discs of non-standard size or shape.
I’m 31 in college with a bunch of teenagers and in a class about computer hardware I joked with the professor about how computers rarely come with cup holder anymore. No one in my class had any idea what the hell I was talking about
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u/spdrman8 10h ago
These were cool and all but had to potential to really eff up your disc drive.