Little things are not critical. Little things decide everything

Unknown repairman

When restoring data and repairing hard drives, many cases are similar as twins – the only difference is the order number and the full name of the HDD model. I decided to outline the usual data loss situations. Given their repeatability, it will be useful for many to familiarize themselves with them.

Outer Rims: Falls

When a terabyte or more capacious external drive of the 3.5 ″ format falls off the table when it is turned on, the spindle often jams in it. A package of 3-4 duralumin plates with a width of 1.6 mm has a decent moment of inertia, and there is usually no corresponding depreciation mechanism in the case, unless a thin sponge gum is for chickens to laugh. Upon impact, the edge of the bearing deforms and seizes. Manual wedging often increases backlash and vibration before disruption of track positioning, and often the entire package needs to be transplanted to the donor spindle. Well, if, in addition, the axis is bent, then the transplant is simply inevitable. The eccentricity is measured using a laser pointer reflected on the ceiling – a sort of mirror galvanometer.

A clean chamber in which transplantation of heads and plates is carried out. The main tool is screwdrivers (including an electric one: unscrewing dozens of screws manually by hand eventually bothers you) and powerful pliers to disengage the positioner magnets

Disk on operation. The upper magnet and head block are removed, the paired heads are separated by plastic spacers (the heads are so polished that they immediately stick together when touched, after which they can be ejected)

But even after the operation, if the data is read, it’s slow and sad. In the event that the drive is almost full, I’m guaranteed a week or two of red eyes. You can’t even imagine how many sectors there are in terabyte or two and what it is like to rewrite them in semi-manual mode. Hence the price of work – from eight to twelve thousand rubles excluding spare parts.