When most people think about hard disk components, they usually think of the disk-heads and the platters. Sometimes people will refer to latter as “the silver things that spin around and store the data”. Not very technical, but it gets the point across. Not many people however think of the less conspicuous parts inside a hard disk. Not many people know, for example, that your hard disk has a small air filter inside it to keep out contaminated air. Not many people know that most mechanical hard disks now use a sophisticated system for parking heads when they are not in use. And not many people know that most mechanical hard disks today use a sophisticated voice coil motor which can position disk-heads with nanometre precision. The modern mechanical hard disk is a derivation of different technological innovations, some of which, took decades to develop and refine.
Another of the lesser-known hard disk components is the fluid dynamic bearing (FDB). This is found in most hard disks manufactured since 2002. With the assistance of a motor, these bearings are responsible for moving the disk-heads smoothly and accurately over the disk platters. The concept of using ball bearings to assist in the operation of mechanical devices is not new. The sketchbooks of Italian engineer Vittorio Zona (1568 to 1603) depict bearings in several industrial applications such as paper mills and printing presses. The concept of using hydrodynamic bearings was first implemented by a British railway engineer named Beauchamp Tower back in 1883. He drilled a half inch hole to supply lubricant through a shaft and noticed how the oil would rapidly rise due to the immense fluid pressures. He also observed how the friction in the shaft was significantly reduced. Today fluid-dynamic bearings offer mechanical hard disk manufacturers the ability to make low-noise, low-vibration HDDs whilst increasing areal densities.
Pre-2002, most hard disk manufacturers used traditional ball-bearings in their spindle motors. These could be extremely noisy and experienced high-levels of NRRO (non-repeatable run-out) meaning their positioning on the platters was not always precise and sometimes even erratic. Moreover, if the disk suffered shock-damage, it was very common for the ball-bearing mechanism to seize resulting in a stuck actuator arm and resultant inaccessible data.
So, what makes fluid dynamic bearings such an improvement? Well, most FDB mechanisms do not use ball-bearings. This means less friction and less noise. Instead, they use an oil-air interface which means the spinning of the disk platters becomes a lot smoother and predictable. The dynamic tilt of the mechanism also becomes more predictable. And it’s not just the oil-air interface which enables these improvements in disk operation. The shaft of an FDB is etched with a herringbone radial pattern. This greatly enhances the stability of the bearing but also greatly helps to dissipate any shocks to the disk.
How Dropping your Disk or Laptop can cause an oil leak…
While the fluid dynamic bearing has been a boon for electro-mechanical disk technology. It’s not perfect. The oil inside the shaft can leak out. This can occur due to external atmospheric pressure, rapid temperature changes, but more commonly occurs if the disk has been dropped by the user. If, for example, your hard disk using a fluid dynamic bearing falls at over 1000G, it is probable that the air-oil interface will disintegrate, breaking the capillary seal and your disk will leak oil. And, if you’re a expecting a mini Exxon Valdez spill on your desk, this won’t happen. The amount of oil used in a bearing shaft is miniscule. In fact, with the naked eye, you probably won’t even be able to see it but you should be able to observe it weeping out with the assistance of a UV light. Once it has been drained from the bearing shaft, the platters will no longer be able to spin and your data will be rendered inaccessible.
“Hard Drive- Not Installed” Dell error message
This is exactly what happened to one of our customers last week. They accidentally dropped their Dell Latitude laptop containing a WD WD10SPCX disk. They booted up the system, but Windows 10 would not load. They ran the Dell diagnostics utility the “Hard Drive-Not Installed” error message was displayed.
How to recover data from the a WD Slim Disk such as the WD10SPCX
Our diagnostics revealed that the fluid dynamic bearing had failed. In this case, the FDB / spindle motor could not be repaired. Instead, using specialised tools, we removed the 2 platters from the problematic disk and migrated them to a chassis of an identical WD10SPCX model. This was an extremely tricky operation. After some precision inter-head alignment and torquing (using a Torx torque screwdriver) of the platter assembly, we closed up the disk. Now there was the firmware issue. If we used the same firmware as the donor disk, it is likely the disk would start clicking immediately. Modern disks are hyper-tuned. Therefore, we uploaded an exact copy of the original firmware onto our data recovery system. This finally gave us full access to the NTFS partition table where we able to recover the data.
This is just one of the problems which can affect WD Slim 2.5” disks. Other problems we’ve come with this Western Digital range of disk include:
- Your WD Slim 2.5” disk is making a clicking, chirping or ticking noise
- Your WD Slim 2.5” disk is not registering with your BIOS or on Windows system
- Your WD Slim 2.5” is spinning, but is not assigned a drive letter.
- Your WD Slim drive appears as “not formatted”
- Your WD Slim drive appears as “not accessible” because the “parameter is incorrect”
- When you connect your WD Slim drive to macOS, you receive the error message “The disk you inserted is not readable”
- When connected to your Windows computer, your WD Slim disk causes your computer to freeze and display a “not responding” error message.
Drive Rescue, Dublin, Ireland offers a complete data recovery service for Western Digital hard disks including the WD Slim, WD Ultra Slim and recovery of WD My Passport Slim disks. Common models we recover from include the WD5000MPCK, WD10SPCX, WD20SPZW, WD20SPZX and WD My Passport Slim (1TB, 2TB and 4TB) . Call us on 1890 571 571. We’re here to help.