The ST1000LM035 is a mechanical 1TB 5400RPM S-ATA mechanical disk from Seagate introduced in 2016. It’s capacity and thin 7mm form factor has proven extremely popular with laptop manufacturers such as Dell, Acer, Asus and HP. The aforementioned companies all desiring to make their computing devices as slim as possible. In turn, since around 2010-2011, hard disk manufacturers have responded by introducing thin form factors (7mm) for their 2.5” S-ATA disks. (The standard 2.5” S-ATA being 9.5mm). However, from our experience spindle motors used in “thin” disks have a high propensity to fail than motors used in standard 9.5mm disks.
Spindle failures such as seizures was an extremely common problem
In early generation hard disks, spindle failures such as seizures was an extremely common problem. Most of these disks using conventional ball bearings had a tendency to experience a phenomenon known as “non-repetitive run out vibration”. This occurred due to nano-metre inconsistencies found on the bearing balls causing read/write interference. In worst case scenarios the spindle would seize altogether making the disk inoperational.
From conventional ball-bearings to fluid-dynamic bearings
Then around 2002-2003, spindle motor manufacturers began using fluid-dynamic bearings. This was a paradigm shift for mechanical hard disk design. Fluid dynamic bearings use a fluid such as oil between the bearings and the shaft. When the shaft rotates the pressure generated by the fluid helps the bearings move more smoothly. While this led to greater disk reliability, it also made hard disks run more quietly and saved computer users the irritation of having to listen to metallic scraping noises.
But the pull of technological innovation never sleeps. Just as spindle motors used in 9.5mm disks were going from “reliable” to “extremely reliable”. Spindle motor manufacturers had to go back to drawing board to design models suitable for 7mm disk form factors. This would mean a complete redesign or a compromised design. Spindle motor size can only be 70-75% the thickness of the disk. Most spindle manufacturers seem to have taken their motor designs for 9.5mm disks and “cut them down to size” to fit the smaller form factor disks. From a reliability standpoint, the “thinner and lighter” trend pervasive in hardware at the moment is a classic example of two steps forward one step back.
Two Steps Forward – One Step Back
With this slimmed down design, the bearings have less room to build a suitable magnetic force needed for a 5400 RPM platter. Maybe this is because the motors used in this form factor are not as reliable as those deployed in 9.5mm disks. (Other 2.5” 7mm disk models such Western Digital’s WD10SPCX and Seagate’s Momentus Thin also exhibit spindle motor problems).
Recovering data from a beeping hard disk
In this particular case, the ST1000LM035 disk which was removed from a Dell laptop was beeping. We transplanted the disk platters containing their client’s data using a customised unwinder tool designed specifically for use with Seagate 2.5” thin disks. We removed the platters and transplanted them into an exact-match Seagate ST1000LM035 donor disk. Platter removal is an extremely intricate job. For a successful transplant, a number of criteria must be met. These include:
- Perfect alignment between the platter unwinder tool and notches of the platter ring. Otherwise torque forces might incur further damage.
- You must apply a clockwise force. Remember, most hard disks spin in an anti-clockwise direction.
- The platter securing ring must be carefully removed with a tweezers. These must be free from any residual magnetic forces and must not touch the platter surface.
- The transplanted platter must align perfectly with the notches on the donor disk. This can be achieved by rotating the platter-tool until you feel a slight click.
- Once the hard disk ramp has returned to its original position the disk lid can be safely closed.
In recovering this disk this methodology was followed. But upon disk initalisation the volume could still not be seen by our host system. Such surprises are to be expected in data recovery. One common reason for such an occurrence is the new spindle not being “tuned” to the new disk. This can be remedied by using a firmware emulator. We did this and restarted the disk. This time a volume appeared with the client’s Word, Excel, Photos, PDFs and .RVT (Revit) files now being accessible. We performed an integrity check on these and they were perfect. These files were extracted onto a USB portable disk and delivered to a very happy customer.
Drive Rescue is based in Dublin, Ireland. We hope you have found this post useful and interesting. We have also successfully retrieved data from the 2TB model (ST2000LM007) of the disk mentioned in this case study. Other “thin” disks which we recover data from include the Seagate Momentus Thin, WD Blue models WD10SPCX, WD10SPZX and HGST Z5K500, 5K1000.