Cost to recover data from disk drive with hole drilled through it?

Question

I took half a dozen disk drives out of ancient computers from an elderly relative's house prior to recycling them. I could have tried to power them up, connect them to a working computer and used software tools to erase them but that did not seem to be a good use of my time. Instead, I put a 3/16" bit in my hand drill and drilled a single hole in each one through the platters. It was quick. It was fun.I am satisfied that this is a suitable defense against any reasonable threat model. Worst case if I had done nothing at all would be the acquisition of a few decades-old tax returns. I think there are easier ways of collecting a few social security numbers, if that is someone's goal.But I am curious. I suspect that state-level actors might actually be able to get something out of a platter with a single hole in it. Is this true? Are there commercial companies that could tackle this? How much would it cost?I bet someone on HN knows the answer, or maybe even has experience with this kind of problem.

LinuxBender · Accepted Answer

If they are spinning rust, then a drilled hole is sufficient against most forms of data recovery. A plastic syringe full of CLR Calcium Lime Rust remover injected into the drilled hole will finish the job.
If money is not a factor then it's a lot easier and faster to take them to a shredding service. [1][2] Shredding disks regardless of spinning rust or SSD will make data recovery nearly impossible.
[1] - https://www.youtube.com/watch?v=sQYPCPB1g3o
[2] - https://www.youtube.com/watch?v=6-onP1XPJwo

eimrine · Answer

If no chips are harmed and luckily no MFT files on the plate is missing then the chance of reading something nasty might be close to zero - if the attacker has some HDD restoring skills. But usually people with this kind of skill have a better use of their time by earning a lot of money and if regular attacker uses HDD restoring service then he has to pay a lot of money to serviceman which seems not worth of it. So, you did a good job if destroying a working thing might be considered as something good.

blinded · Answer

Plenty of legit (non state actor) services that do this ie. my google produced this asa the top result after the ads https://drivesaversdatarecovery.com/data-recovery-services/d...

rolph · Answer

you would need software that does low level disk access with the ability to just ignore a problem and carry on with the read. most important is you need to find the directory listings on the drive to align the bits into meaningful files.
you may also have a problem with the hole unbalancing the platter and causing orbital procession.
profe$$ional cost$ for thi$ a$ a $ervice is extreme.[$$$]
[also] you may find this informative:
https://www.datarecoup.com/blog/hard-drive-recovery/hdd-low-...