When we have to open a hard disk drive (open desktop hdd, open laptop hdd), we should know what screwdriver shall we use to open it, we also should know what type and size to choose that would fit the hard drive screws. Actually, most hard drives use philips or torx screws. Torx screws are used very heavily on the internals, it used to repair computers, cell phones and other small electronic. T6 & T8 are the most common size and PH0 and PH1 are the most common for philips.
There is neerly no way to open it without the torx driver as anything else will strip the head of the screw. Sometimes we made the mistake of using a phillips or other head screwdriver on the torx screws, this may destroy the screws.
Torx Screwdriver System
The Torx system was introduced in 1965 by Camcar, and patented in 1971. Its great popularity, however, really began in the 1980’s, when it became very common in trucks and automobiles.
The walls of the recess are not tapered, so camout is absent. Drivers greatly outlast similar hex head drivers. The same system of sizes is used for both metric and inch fasteners.
Internal Torx Screwdriver Size
Driver sizes for Torx recesses begin with a T. The dimensions below are measured on the driver bit, from point to opposite point.
| Size | point to point, millimeters |
|---|---|
| T1 | 0.81 |
| T2 | 0.93 |
| T3 | 1.10 |
| T4 | 1.28 |
| T5 | 1.42 |
| T6 | 1.70 |
| T7 | 1.99 |
| T8 | 2.31 |
| T9 | 2.50 |
| T10 | 2.74 |
| T15 | 3.27 |
| T20 | 3.86 |
| T25 | 4.43 |
| T27 | 4.99 |
| T30 | 5.52 |
| T40 | 6.65 |
| T45 | 7.82 |
| T50 | 8.83 |
| T55 | 11.22 |
| T60 | 13.25 |
| T70 | 15.51 |
| T80 | 17.54 |
| T90 | 19.92 |
| T100 | 22.13 |
External Torx Screwdriver Size
The sizes of the external drivers, which are less common, begin with an E.
| Socket Size | Point to point, internally milimeters |
|---|---|
| E4 | 3.8 |
| E5 | 4.7 |
| E6 | 5.6 |
| E7 | 6.1 |
| E8 | 7.4 |
| E10 | 9.3 |
| E12 | 11.1 |
| E14 | 12.8 |
| E16 | 14.7 |
| E18 | 16.6 |
| E20 | 18.4 |
| E24 | 22.1 |
Torx screwdriver system is very popular in the automotive and electronics industries because of resistance to cam out, and extended bit life, as well as reduced operator fatigue by minimizing the need to bear down on the drive tool to prevent cam out. A tamper-resistant Security Torx head has a small pin inside the recess. Owing to its six-fold symmetry, a Torx driver can also be used as an improvised substitute for a hex driver, although careful sizing is critical to prevent stripping the socket.