By Karim Salmi / Data Recovery / 0 Comments

Hard Drive Mechanical Arm Failures 101

Article 3: Hard Drive Mechanical Arm Failures 101

Welcome to this third article of the VitalTech hard drive and data recovery blog series. We’re going to look at the hard drive mechanical arm and go through the common issues you may face that can include unexpected contact with disk platters (scratching), reading wrong areas, and degrading when reading over a dent in disk platter at 5400rpm or more.

Other Articles in This Hard Drive and Data Recovery Series

Note: Each of the titles below, when clicked, will transport you directly to that information.

Article 1: Your Hard Drive (How It Works and What Causes It to Crash)

Article 2: The Basics of Modern Hard Drive Disk Failures

Article 3: Hard Drive Mechanical Arm Failures 101

Article 4: How Hard Drives Save and Retrieve Your Files

Article 5: Hard Drive Printed Circuit Boards and Data Recovery Explained

Article 6: An Intro to Internal Hard Drive to PC Connections

Article 7: External Hard Drives and Data Recovery

Clicks, scratching or grinding noises, low and degrading disk RPMs, popping sounds, computer freezes, oh my! Oftentimes the first signs of hard drive trouble come about as a result of the mechanical arm and the components that make it possible for it to do its job.

up close view of a hard drive mechanical arm and head

Actuators are there to move the arm, the central spindle spins the platter so the read-write head can access/imprint data while the small spindle makes it possible to swing back and forth. Then of course you have voice coils, bearings, and motors involved as well.

So many things can go wrong! As one issue crops up, it can cause another due to the synergistic nature of the way the mechanical arm fits into the “hard drive puzzle” if you will. But as mentioned, lets take a brief look at the three most common failures we deal with as data recovery experts.

3 Sure Signs of Mechanical Hard Drive Issues

  1. Platter Contact: Uh oh, you dropped your external hard drive or mobile device now it’s acting funny? It’s begun making sounds? Maybe the platter has been knocked off kilter or the spindle motor is damaged, but whatever the scenario it’s caused the frail read-write head to crash into the platter. In this case disk damage can range from minor to catastrophic and unrecoverable.
  2. Improper Data Reading: Wait a minute, why are files suddenly disappearing? Are entire sectors of data being skipped over? Perhaps the File Allocation Table has been destroyed, or maybe platter alignment is off and they’re clashing. Or, it could be that improper venting is causing too much heat and plates are spoiling.
  3. Disk Platter Dents: When platters, or hard drive disks (HDD) are distorted, dented, or bent in some way, yes, they become essentially unreadable for the mechanical arm’s read-write head. Even tiny misalignments can wreak havoc leading to a full hard drive crash, or at a bare minimum completely destroy data in certain sectors if you continue to try and use the hard drive once these things occur.

For almost all these cases, we have the tools to extract and recover data from hard drives that have suffered extensive mechanical damage. But, to be frank, some people get lucky and discover that despite a bent disk for example, their most important data wasn’t harmed. It’s all quite situational.

A computer guru with ten years of professional experience. From corporate IT to forensic data recovery, he has seen it all and has the stories to prove it. His hobbies include programming and ice hockey.