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Sony PSP Usage Inclusion[edit]

The PSP modding scene relies heavily on torx screwdrivers. Somebody could make a note with this if they'd like. Thanks! Tegrofi (talk) 14:15, 23 July 2008 (UTC)

yes and so does everyone else in the world PSP modders aren't special. Torx screwdrivers are used everywhere across the world. —Preceding unsigned comment added by (talk) 18:01, 19 October 2008 (UTC)

Dead Links?[edit]

The first two links on the page are dead. Are we to replace them, or omit them? Rny2

You'll have to be more specific. JimScott (talk) 01:09, 22 May 2012 (UTC)


What is cam-out? Mathiastck 21:05, 18 August 2006 (UTC)

Phillips screwdrivers and screw heads have internal mating faces engineered slightly off parallel rather than parallel to the driver shaft as in the case of a competing GKN-Sankey(c) Posidriv design. Cam-out occurs when the force required to turn the screw head further has exceeded that required to force the screwdriver's pressure faces to rise up the corresponding sloping cams of the screw head's internal surfaces and emerge. Variable factors - the hardness of the screwdriver's point and screw head, existing wear in the mating surfaces, lubricant contamination, and the proportional relationship of the downward pressure applied to the torque applied, etc. - mean the point at which cam-out will occur may be considerably lower than in a perfect-case scenario. (talk) 17:24, 29 May 2008 (UTC)

In other words, when you turn a Phillips screwdriver in a Phillips head screw, to undo the screw, and the screw is too tight, and the screwdriver tip starts to come out of the head, that's cam out. It's like there are 4 tiny ramps, which make the screwdriver come away from the screw. Or what might happen is stripping of the head, in which the metal of the screw gives way, and you end up with a damaged screw head, in which you have to now apply a lot more force, to undo the screw, in order to overcome the missing metal. This can often lead to MORE damage to the screw head, unless you can apply a LOT of pressure and it should be *perpendicular* to the screw head, combined with slow turning of the driver and close monitoring of the condition of the screw head. That's why other screw heads are preferable where you don't want this to occur. DaveDodgy (talk) 15:49, 1 November 2008 (UTC)

TORX Stripping?[edit]

"They are generally disliked by the do-it-yourself community due to being much harder to remove compared to their hex head counterparts, as the torx head/bit are much more prone to being stripped/broken." One of the claimed advantages of the TORX drive system is resistance to stripping/breaking. Is there any proof for this statement? —The preceding unsigned comment was added by (talkcontribs) 04:12, 27 October 2006 (UTC).

I know this is anecdotal evidence as well as original research but pretty much every Jeep owner that I know who modifies their Jeep (lift kits, bumpers, etc.) and I know quite a few, takes the time to replace the torx bolts with hex bolts whenever they need to remove a torx for a modification. Some even go so far as to replace every torx bolt, from front to back, inside and out, with a hex bolt, allen head, or machine screw whenever they buy a new (or used) Jeep. Every one. Just so that they don't have to deal with another torx on that vehicle ever again. Just a few links to prove my point... [1], I've removed almost every last torx bolt from my Jeep, been replacing them with stainless bolts and washers, i myself have ran into that damn torx problem. What works the best is drilling out the torx head, and using vise grips to unscrew the rest of the bolt. Usually, it unscrews very easily. Dismas|(talk) 04:28, 27 October 2006 (UTC)
The statement is specious and should be removed. Thousands of mechanical and manufacturing engineers who've put Torx fasteners into hundreds of industrial and consumer products by the millions over recent decades aren't wrong. Not only the originator of the Torx drive system, but hundreds of manufacturers have proven that Torx drivers last 10 to 20 times longer than competing tools in high volume assembly. Head stripping by do-it-yourselfers can invariably be traced to using damaged tools, using the wrong size Torx bit for the fastener, or attempting to force frozen fasteners. On that basis, NO fastener system could be considered adequate. —QuicksilverT @ 21:59, 20 November 2006 (UTC)
Agree this should be removed, I have read the spec sheats and worked with both hex and Torx fasteners for years in many industries and have striped the head and many, many more hex fasteners then Torx (on a percentage basis). Acctualy it's be a month I'm pulling it and the neutrality warning.Raelx 04:53, 23 November 2006 (UTC)
While I do agree that Torx is typically less prone to stripping than Phillips or internal hex, in my anecdotal experience external hex bolts are less prone to stripping when they are aged (rusty) and require a lot of force to loosen. Hydrargyrum's point about engineers is true, but you have to be careful to distinguish between what works well for initial construction and what works well on a machine subject to years of hard use and corrosion like a vehicle. Also keep in mind that engineers and manufacturers work to save costs and simplify build but don't always take long-term maintenance into account, especially with something like a vehicle where it might be in service for far longer than the expected equipment lifetime. While a Torx drive screw in a computer might be perfect and last the lifetime of the equipment, one on the exhaust system or suspension of a vehicle would rust in both the threads and the drive head, potentially causing a stripped and frozen connector. I wouldn't consider the statement "specious" but would advocate clarification or expansion of the statement, hopefully with some well founded sources.Dculberson 15:25, 2 May 2007 (UTC)
One could draw the conclusion that the problem may be related to Jeep owners but that would be a gross simplification of the problem. The basic problem is that Torx-headed screws were designed as a manufacturing convenience. They weren't really intended for ease of removal by the general populace. While the wholesale changeover from Torx-headed bolts to hex headed-bolts is a little over-kill IMHO, in their defense, Torx-headed fasteners do require that one has a proper set of properly-sized tools and the knowledge of how to use them properly; whereas hex-headed fasteners can be undone by a myriad of common hand tools including the ever-popular "metric" hand wrench using good old elbow grease. Success in removing Torx-headed fasteners is improved by completely cleaning any rust and/or debris out of the socket and using only the correct size; obviously not a problem with the hex-headed variety. JimScott (talk) 01:27, 22 May 2012 (UTC)

T0.5, T1.0 notation?[edit]

Some Torx screwdrivers are referred to by another notation, T0.5, T0.6, T1.0, etc. Such as these. How does this relate to the T4, T10, T20 etc notation? Caliston 19:26, 27 March 2007 (UTC)


I don't think this deserves mention in this article. It is not a Torx design, just one of several 6-lobe drives unrelated to Torx. —Preceding unsigned comment added by (talk) 02:19, 10 September 2007 (UTC)

Torx sizes[edit]

The Wiha reference for Torx sizes is out of date. There are now T35 and T47 bits, and presumably Torx fasteners that they fit. —Preceding unsigned comment added by (talk) 19:30, 29 December 2007 (UTC)

I wanted to find a table relating torx sizes to screw sizes; eventually I found one on Is this something which should be added to the page? —Preceding unsigned comment added by (talk) 15:03, 21 January 2008 (UTC)

T3 (here), T4 (here) and T5 (here) aren't on the list. (talk) 23:08, 14 June 2011 (UTC)

5-pointed star Torx Variant?[edit]

Apparently some manufacturers are now using a 5-pointed star Torx variant that seems to be distinct from Torx Plus (with smaller cutouts for the points, giving the appearance of a "fatter" star), Security Torx (with the pin in the middle that prevents placing a standard driver in the screw), 5-lobed "Security Torx Plus" (which looks like a 5-lobed combination of the previous two variations), and TTAP (where the screws have a recessed round hole in the middle). These screw have a hole that looks like a plain 5-pointed star and are easy to mistake for a standard TORX screw. I came across these on Toshiba-manufactured iPod hard drives, and found other people griping about them on car parts and consumer electronics hard drive cases. The screws on the hard drive in question are approximately the same size as a standard Torx T4, but the 6-pointed star of a T4 driver head won't. It is possible to turn them with a flat-head screwdriver of approximately the right width but because the fit is not precise, damaging screw and/or driver is likely.

Really a pain; if anyone has authoritative info (like a canonical name for these) it would be welcome. I hate the idea of proprietary fasteners you can't buy tools for!Paul R. Potts (talk) 19:54, 14 February 2008 (UTC)

Driver control[edit]

"Drivers for the tamper-resistant version are tightly controlled by Camcar, and are sold only to OEMs (along with the fasteners), or OEM-authorized repair facilities."

After seeing a tamperproof Torx driver or bit, the Chinese factories simply make them, and then churn them out, by the 1000's. No need to ask for permission! They should be licensed manufacturers, but they aren't. Not to say that there aren't, but > 95% of them.DaveDodgy (talk) 16:02, 1 November 2008 (UTC)

This isnt true, and hasnt been for quite some time. These drivers are widely available at sears, auto parts stores, tool mfgs. like snap-on, etc. Furthermore, you can make your own tamperproof bit by drilling the center of a conventional torx.

Not if you have a quality bit/driver. The centre, where you wish to drill, should be very hard metal. Too hard to drill typically. Soft bits sold cheaply can probably be drilled easily. Often they come like this, and the hole is pathetically off-centre, or too big or too small! DaveDodgy (talk) 16:02, 1 November 2008 (UTC) —Preceding unsigned comment added by (talk) 19:37, 26 February 2008 (UTC)

Measure of Torque[edit]

Shouldn't the measure in the table be in Nm-1 instead of Nm? —Preceding unsigned comment added by Simonalexander2005 (talkcontribs) 17:26, 29 February 2008 (UTC)

No, because Nm-1 is Newtons per metre, while Nm is Newton-metres. torque = force * distance, so we have Newton-metres. For example, if you apply a force of 20 N to a 250 mm-long spanner, you are applying a torque of 5 Nm (20 * 0.25). (talk) 10:38, 6 March 2008 (UTC)

So torque has the same units as work ? They're quite different, though, aren't they? The distance in torque is from the centre of rotation when a force is applied, whilst in mechanical work it's the distance moved by the application of a given force. Is there a relationship? Is torque a specific kind of mechanical work? Mr. Jones (talk) 10:18, 9 August 2008 (UTC)

My belief is that work done and torque are unrelated, because torque uses a distance perpendicular to the force, and work done uses a distance in the direction of the force, so the only similarity is the units. (talk) 23:13, 14 June 2011 (UTC)

The distinction between the two physical quantities of torque and of work is fundamental to an understanding of mechanics. To specify a vector quantity, one must specify the direction of the quantity as well as its magnitude. The physical quantity of torque is defined in classical mechanics as the vector (or cross) product of force (a vector physical quantity) and of displacement (also a vector physical quantity). Torque is therefore a vector quantity. By contrast, work is the scalar product of force and of displacement. Work, being a scalar quantity, has magnitude therefore but no direction. — Preceding unsigned comment added by (talk) 12:47, 11 October 2011 (UTC)


Is torx properly pronounced "torks" so that it rhymes with "forks" or is it pronounced "torrex" or "torr-X"? And while we're on the topic, is the "driv" in pozidriv pronounced as "drive"? (talk) 10:52, 6 March 2008 (UTC)

>Is torx properly pronounced "torks" so that it rhymes with "forks"[?]
Yes, correct.
>is the "driv" in pozidriv pronounced as "drive"?
— ¾-10 00:33, 7 March 2008 (UTC)

Inch vs. Metric=[edit]

There are dimensional discrepency's on the Whiha charts between inch and metric. Some large enough to prevent interchange. I currently have equipment that should take T6 per instructions, however a T6 is too small, T8 too large. What's up with that? Per the article, Torx should have only one specification to avoid the inch vs. metric tool hassles. —Preceding unsigned comment added by (talkcontribs) 18:52, 22 May 2008 (UTC)

It's true: The driver size is independent of threads. You might have some counterfeit ChiCom fasteners or drivers. TORX is still under trademark protection, but since the patent on the original TORX fastener design ran out in 1991, the copycats have been doing who-knows-what to it. It's unlikely that you're dealing with TORX PLUS screws, 'cause the article says a standard TORX fastener will fit them loosely and can drive them.—QuicksilverT @ 00:39, 19 May 2010 (UTC)


It'd be useful to have some sort of timeline, showing when these were first introduced (and in different countries too). Here in the UK they are now quite common, but when did this start to happen? This could be useful for dealing with older equipment, though I suppose everyone who might need to deal with any of these will just have to bite the bullet and buy a set of Torx bits. It's not a problem with older equipment though - seems only to have happened in the last couple of years on a wide scale.David Martland (talk) 16:25, 29 June 2008 (UTC)

Compaq were putting them on PCs manufactured in 1993 or so (I think: pentium 90s with 32Mb of RAM). Beyond that, I don't know. Mr. Jones (talk) 10:21, 9 August 2008 (UTC)
Not sure of the precise date that TORX was introduced to the market by Camcar Textron, but my dad had a 1974 Ford Econoline passenger van (made in the United States) with TORX bolts to secure the seats and seat belts. They were developed in the mid-1960s and a patent was awarded for the hexalobular drive system in 1971. See —QuicksilverT @ 00:29, 19 May 2010 (UTC)
Also curious about the history. I first saw them securing seatbelts in a 1973 Oldsmobile Cutlass. Thought they were some sort of "security" fastener to discourage removal; was probably an early adoption of the tech' for a high strength, safety critical app. The 1960s development and 1971 patent sounds reasonable. Verifiable? —Preceding unsigned comment added by (talk) 15:21, 1 March 2011 (UTC)

Minor adjustment re: Compaq[edit]

As Compaq was bought by HP, shouldn't the line "Compaq uses..." be "Compaq used..." ??

Not that it matters greatly but H-P still produces the Compaq line of computers so the present plural usage is fine also. JimScott (talk) 01:31, 22 May 2012 (UTC)

Are HP|Compaq computers still being made using T15 screws? DaveDodgy (talk) 15:36, 1 November 2008 (UTC)

Who cares? There are now thousands, if not tens of thousands of products that use TORX fasteners, and that is a level of detail that is inappropriate for this article. I removed the reference to Compaq computers.—QuicksilverT @ 00:35, 19 May 2010 (UTC)

Say what the 40 in T6x40 means[edit]

You sirs have blown it in your responsibility to explain what the 40 in "T6x40" means. A mere

A smaller number corresponds to a smaller point-to-point dimension of the screw head.

is not good enough or even clear, and in all ASCII .TXT files the numbers are the same size too. Jidanni (talk) 00:37, 28 November 2008 (UTC)

This paragraph is incorrect or in error[edit]

"There is also a tamper resistant version of TORX PLUS, having five lobes and solid post in the center. This is used for tamper resistance as the drivers are still hard to obtain, and are given the designation 'Torx TX'." I've been researchind trying to find 5 Point Torx sets (affordable) and NO ONE calls them Torx TX...they refer to the "standard" 6 Point Torx & 6 Point Security Torx as TORX TX but not the 5 Point star security/tamper proof. Here's just one example of the Torx TX & Torx TX security: is by no means the standard name. This is a JUMBLED MESS. How hard is it/would it have been to come up with a standard name for the 6 Point / 6 point security and 5 pt / 5 pt security? —Preceding unsigned comment added by (talk) 06:04, 5 July 2009 (UTC)

I agree. A number of unrelated drive systems have been creeping into the article. They should be purged to eliminate confusion. They aren't called TORX by their manufacturers, so why include them in this article? If they're important enough, give them each their own article, or if they're so rare that only a few hundred people in the world have ever heard of them, dump them into a collective "security fastener" article.—QuicksilverT @ 00:44, 19 May 2010 (UTC)

Torx vs. x[edit]

This article only compares Torx to Phillips, but it says it is used in place of hex and Allen headed fasteners, and looks like Robertson (and square) as well. Tehre should be information on why they are used in place of those other things . (talk) 11:29, 3 September 2009 (UTC)

External sizes?[edit]

A list of the external sizes and how they *don't* correspond to the internal sizes would be useful. I'd thought the Torx socket for a bolt with a head the same size as a T-20 Torx driver tip would be an E-20, but nooooo, that would have been too dang simple and logical. (talk) 07:58, 30 December 2010 (UTC)

Textron distributor web site[edit]

There is a splendid index page at [:]. perhaps someone could ask them to put the text and pictures into creative commons for use on WP? --Robert EA Harvey (talk) 09:22, 29 October 2012 (UTC)

Würth AW, SIT, ASSY[edit]

Wurth has torx-derived design that they call as AW. It's used in their ASSY screws, that include some other unrelated inventions too. They seem to call their current screw design as "ASSY 3". I guess there has been revisions on it. I'm not sure whether they have changed that AW head for a while, thought. I'm guessing that relevant patent is US5435680 from 1995.

Other manufacturers (Wera, CELO) seem to offer drivers with "SIT" head, that are supposed to be licensed from Wurth and designed for ASSY screws. So it looks like that SIT=AW, or is it? SIT screw is supposed to be able to be driven with regular torx, albeit with imperfect fit, see . Is this properly documented anywhere? Any insight? — Preceding unsigned comment added by Jesh (talkcontribs) 22:32, 4 January 2013 (UTC)

Point to point ?[edit]

There are size tables in the article, and they mention "point to point distance". However, I can't find any definition of this distance, which means the tables are essentially useless. Does anyone have a source for how this distance is defined? (talk) 17:22, 23 December 2013 (UTC)

Isn't it simply the distance across two diametrically opposed points of the star? To confirm that, you could throw a caliper across a handful of males and verify them against the table to see if the numbers correspond (± 10 thou). Until that's done, I don't really see how the tables can be judged as "essentially useless". I would even go caliper some myself, with curiosity piqued by this thread, but I'm working. — ¾-10 22:38, 23 December 2013 (UTC)