Data Recovery Case File · Trust, Practice & Honest Limits · Half Right Is Worth Something
Heads Are Not Adjusted, and Moving Platters Is the Hardest Thing There Is
His enquiry arrives with a diagnosis and a proposed remedy. The head assembly "has become out of sync with the disk and therefore will not read the data", and it is "a simple enough thing to either transfer the disk to another housing or adjust the arm so the data can be retrieved." His reasoning is closer than most, and the two operations he describes are real ones — they are simply the opposite of simple, and one of them is a last resort rather than a first.
| Media | Hard drive not reading — owner attributing the fault to head-to-platter positioning; owner proposing platter transfer or head adjustment as remedies |
| Reported situation | Drive not reading stored content · fault attributed by the owner to the head assembly being out of alignment with the platters · transfer of platters to a different housing proposed · adjustment or replacement of the head assembly proposed · recovery or rescue of the content sought |
| Fault class | Positioning or head-assembly failure indicated — assembly replacement feasible under filtered air; platter transfer viable only where the assembly cannot serve and carrying substantially higher risk |
| Equipment used | Owner's diagnosis assessed against measurement before any route was chosen · current draw measured across the start-up cycle on a controlled bench supply · laminar flow bench inspection with head and platter surfaces assessed before any rotation · matched donor head assembly fitted where indicated · platter transfer held in reserve as a last resort with alignment preserved |
The decode: what is right in his account, and what the two operations really involve
What he has correct, and it is not trivial: the fault class. A drive that spins and does not read very often does have a positioning or head problem, and he has reasoned to that from the symptom.
Why heads cannot be adjusted, in the sense he means: there is nothing to adjust. Positioning is not set by a mechanical alignment but by the drive continuously correcting itself against reference information written on the platters.
What that means practically: the assembly is replaced, not tuned. A head assembly is fitted from a matched donor drive, and the drive then re-establishes its own positioning against the same references.
Why replacement is nonetheless demanding: the tolerances are extreme. Heads fly closer to the surface than the width of an airborne particle, so the work happens under filtered air and the assembly must never touch the recording.
Why the donor must be matched rather than merely similar: the electronics are calibrated. Heads are paired with their drive's adaptive parameters, and a mismatched assembly reads nothing useful.
Now his other proposal, which is the more serious one: moving platters to another housing. It is a genuine technique and it is the most difficult operation performed on a drive.
Why it is so difficult: the platters must keep their relationship to one another. On a multi-platter drive, rotational alignment between them must be preserved exactly, and disturbing it makes the data unreadable permanently.
Why it is a last resort rather than an alternative: it is chosen when nothing else will serve. Where the housing or motor has failed and the assembly cannot be used in place, platters are moved — and not before.
Why the order matters more than the choice: nothing is decided before inspection. Which fault is present is established by measurement and by looking, rather than from the symptom.
What must not happen meanwhile: no further power. If heads are contacting the surface, every rotation costs recording that cannot be replaced.
On the bench
The owner's diagnosis was assessed against measurement before any route was chosen — a drive spinning without reading frequently indicating a positioning or head fault, though positioning is maintained by continuous correction against reference information on the platters rather than by mechanical alignment, so assemblies are replaced from matched donors rather than adjusted. Platter transfer is genuine but is the most demanding operation, requiring rotational alignment between platters to be preserved exactly. Inspection preceded any rotation.
The outcome
The diagnosis assessed against measurement, surfaces inspected under filtered air before rotation, and a matched donor assembly fitted where indicated. Free assessment, one fixed written figure including VAT, 50% of parts and labour upfront with the balance only on successful recovery. The decode: you have reasoned to the right fault class from the symptom, which most people do not. Heads are replaced rather than adjusted — and moving platters is the last resort rather than the easy alternative.
If you have worked out what is wrong with your drive
Say so — reasoning from the symptom to a positioning or head fault is genuinely useful and often right. Two corrections worth having: heads aren't adjusted, because positioning is maintained by the drive continuously correcting itself against reference information on the platters, so the assembly is replaced from a matched donor instead. And moving platters into another housing is real but is the hardest operation there is, requiring rotational alignment between platters to be preserved exactly. Don't power it meanwhile.
Bring your reasoning — call Cambridge Data Recovery on 01223 655015; your diagnosis assessed against measurement, surfaces inspected under filtered air before rotation, matched donor assembly fitted where indicated.
Request a quote online →
Our case files are drawn from genuine enquiries received by our laboratory over the past ten years, anonymised to protect client confidentiality. Each one describes the diagnostic and recovery procedure our engineers apply to that fault, using the equipment listed.