Bad idea to stack 2.5 hard drives?

Discussion in 'SSDs & Data Storage' started by AlienTech, Aug 15, 2018.

  1. AlienTech

    AlienTech Limp Gawd

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    I have stacked 100's of 3'5 and even 5 and 12 inch drives without noticing any problems. But the other day I moved 2 2'5 inch drives for cloning to use on a laptop and media device and since capacity was different I wanted to make sure they were the same physical size. So All I did was align them to see if they matched. Both were WDC drives, 1 being one of those video storage units and the other a regular hard drive.

    Now I was able to clone an image onto the video storage drive and put it in the lap top and it worked fine. The regular hard drive which was in the lap top and working fine, when hooked up to the desktop showed pending sector write errors during clone and failed. Checking the drive showed banks of errors.. 2 blocks would be fine but then the next 2 or 3 would be bad.. Seems to be where the motor of one hard drive was slid across the top of the other caused the markers to demagnetise.

    I have many times cloned these same hard drives. Never had any problems but this was the first time I had stcked 2 of them to check the sizes. I know the magnets inside the drives are strong but usually they are held in place with a rod whoch stops the magnetic fields from causing problems.

    Looking at some other 2'5 drives it seems similar to 3'5 drives only smaller.. But it seems the thinner case does not stop magnetic interfearences and might destroy the drive sif you are not careful about external magnets.

    So just saying, unlike stacking 3'5 drives ontop of each other which does have pretty strong cases, doing the same with 2'5 drives might cause a disaster.. I haev seen storage racks but they have a tray in between each of them. Which might be the safe way to stack them.
     
  2. Tiberian

    Tiberian DILLIGAFuck

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    The magnetic fields inside the housing aren't going to affect drives in a stacked configuration - if the fields were strong enough to affect the area around them that easily they'd wipe the very platters inside the housings too which wouldn't be a good thing. I would suspect the potential bad sectors being caused by possibly moving the drives around more than anything else, or they could just have some defects that haven't presented themselves this till point in time.

    I've actually taken the magnets from inside 2.5" hard drives (used for the head assembly armature) and had them stuck to the tops of other 2.5" hard drives and they never had any issues because of the magnetic field penetration. Hell, I've even tried to use a 120 volt handheld bulk eraser (which produces a very powerful field) on a physical hard drive (3.5") years ago and the drive contents in terms of the data on the platters survived so, consider that a drive housing might just work as a Faraday cage-like idea and actually protect the inside of a housing. I couldn't explain it myself but it happened.
     
  3. pendragon1

    pendragon1 [H]ardForum Junkie

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    ive stacked 2.5 without issue for years. maybe that drive was just on its way out and you didn't realize it.
     
  4. Spartacus09

    Spartacus09 [H]ard|Gawd

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    The cases are stronger because the platters are larger and therefore more prone to physical damage, not due to magnetic field.
    I agree sounds more coincidence than causation.
     
  5. SvenBent

    SvenBent 2[H]4U

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    I've stack both 3.5 and 2.5 inch driver without issues
    But i usually put a piece of paper in between them just to avoid any risk of shorts
     
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  6. pendragon1

    pendragon1 [H]ardForum Junkie

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    yup it is a good idea to insolate them if they are powered.
     
  7. AlienTech

    AlienTech Limp Gawd

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    The drive was working fine and I have handled a lot of drives. So if any other condition I would know. And yes I know it rarely happens. But it did.. So for errors to develop in an arc shape would mean either the drive beign dropped and head scratching or the platter losing its sync marks caused by an external magnetic interfearence. The magnet inside the motor is what I think caused this problem not the magnet used for the head assembly or arm movement. I have like 20 3'5 drives stacked whichout any problems. But those cases are also much thicker. The magnet attached to the assembly also seems designed to stop straying magnetic fields so the platters will not be affected since they wont stick to any metal at all on the other side.

    The drive itself has 10TB write and 20TB reads.. And after an error scan it reallocated 140 sectors but lots more errors to be fixed.. Since this is a first for me, I thought I might as well see if anyone else saw a similar issue..
     
  8. Tiberian

    Tiberian DILLIGAFuck

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    It's one drive from what I can tell so, more likely that the one drive is exhibiting some defects or failure than the situation being related to the stacked nature. If it's just one drive, that's telling, two drives next to each other, possible indication of an actual stacking issue, more than two drives, a definite pattern, but since it's just the one drive then again it's more indicative of a drive defect or failure than anything else.