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Cake day: June 6th, 2025

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  • Yeah I’m not actually talking about the “Please place the item in bagging area” part, I’m talking about the second or two after I place it before the system registers the weight and re-activates the scanner.

    Sometimes I’ve seen this disabled, on certain tills at certain supermarkets, and I can scan breezily. Not sure if the weight check feature was disabled completely or what.








  • Having a RAID array would make OP’s question somewhat moot - because a drive failure would be less significant.

    You and others are focusing on addressing the likelihood of the risk. I’m saying it would be better to address the severity instead. The comment is relevant, just slightly more abstract, but very much on topic.

    You’re right that motherboard RAID is worse than OS RAID. I just wasn’t sure what OP’s backup device actually is, if it’s a PC or some simple bespoke NAS box. But it’s more Hardware Controller > OS > Motherboard, generally speaking.



  • Depends how much storage you’re looking to get. https://diskprices.com/

    Looking at new only, you can get a 3TB drive for $36 on Amazon. 3 of those for $108, 6TB storage with n-1 redundancy. Add $36 for 3TB as many times as your controller will allow (or 4, that’s all they have in stock lol).

    diskprices.com also has variants for European and other Amazon. Or you could check other retailers. Also the “used” drives are very cheap - these are typically refurbished datacentre drives. They’ll have a shorter lifespan, but that’s still probably better than a single drive with no redundancy.

    This kind of thing is worth spending money on. Otherwise your backup solution isn’t really a good backup solution, if you’re worried about it failing.

    Edit: Also it isn’t complicated to set up at all. RAID 5 has slightly more setup, but RAID 1, 0 & 10 are widely available natively in most motherboards, and have been for decades. If you’re already setting up some external backup device, it really isn’t much extra, for a good payoff.



  • Why aren’t you running your drives in a RAID array? RAID 5 is n-1, meaning you get n-1 total storage space and can withstand any 1 drive failing. You do need at least 3 drives, but that’s what you should be doing - not just running a manual mirror backup or whatever. You also get the speed advantage from striping data across the drives (although this speed is nothing to an SSD).

    If you really want to be serious about backing up then it’s 3,2,1 - 3 copies, on 2 different types of media, with 1 in an off-site location. As a minimum.

    But first off I think you should upgrade your long-term backup to have some kind of RAID array. With 2 drives you can do RAID 10 (RAID 0 and RAID 1 combined), you’ll only get the storage of 1 drive but you’ll have one to one redundancy and striping. With 3 or more drives do RAID 5 so you’ll have more storage (eg 3x 8GB drives would give 16GB, 4x 8GB would be 24GB, etc), striping for speed, and also the same n-1 redundancy.

    You may need a PCIe card for RAID 5, not all motherboards support it natively. You should be able to find a decent one for not too much, if you look around. RAID 1 and 0 (and maybe 10) often are supported natively.


  • Not quite. A commutator kind of pulses the supply to the rotor, eg a brushed motor would have two brushes up against the commutator, the brushes deliver DC voltage which energises a coil, creating a magnetic field that pushes against a stator that’s made of a permanent magnet. This rotates the rotor and commutator, which then moves the brush around to the next contact on the commutator, engergising a different coil so that the next coil pushes the motor around. The brush maintains a constant DC voltage, but the commutator connects this to different coils as it rotates.

    This is a DC brushed motor, with windings on the rotor and the stator is just magnets:

    And this is a commutator on top of a universal motor (which can run on either AC or DC):

    The stator you have has its own windings, so it would be the stator that pushes against the rotor in that motor, rather than the rotor pushing against the stator like the brushed motor. So you just need to supply an AC voltage to the stator windings and you’ll get a rotating magnetic field, which can then move things inside with their own magnetic fields, eg a magnet, or the rotor it came with.

    I wouldn’t really suggest doing this though hah. For starters, messing with supply voltages and bare windings can be very dangerous, and second if the magnet isn’t balanced it could fly out. And I’m sure there are a bunch of other risks as well lol. There’s also no telling why the motor didn’t work anymore, and it definitely won’t work as well as with the rotor that was designed for it.

    Here’s some fun with a mitre saw motor: https://www.youtube.com/watch?v=iTcjMKs5mek