Torx socket and Star drives

[southerly95]

Does anyone know if the Torx socket bit range prefixed 'T' are matched numerically with the Star socket 'E' range. In other words is a T20 the same size as an E20 only they don't look the same to me? Thanks, John

[MarkyB]

Good question, this page suggests the two terms are interchangeable;
http://myword.info/definition.php?id=t_drive_1-a

A search on Ebay for star socket suggests the same.

[Mogwai]

Torx headed bolts/screws are the work of the Devil
The E ones are a lot bigger for a given size no
T20 is usually on small screws & the E20 on large bolts M14 dia etc

[WPR678B]

Torx headed bolts/screws are the work of the Devil

Couldn't agree more!

[MarkyB]

the work of the Devil

Not at all, Torx is an engineering solution.
"Torx heads were designed to prevent cam-out. The reason for this was the development of better torque-limiting automatic screwdrivers for use in factories. Rather than rely on the tool slipping out of the screw head when a torque level is reached, thereby risking damage to the driver tip, screw head and workpiece, the driver design achieves a desired torque consistently. The manufacturer claims this can increase tool bit life by ten times or more."
From http://en.wikipedia.org/wiki/Torx

Take a look on the right hand side of the page for some other types, or here; http://en.wikipedia.org/wiki/Polydrive for a longer list including The Bristol screw drive, which I've never seen before.

[mike.perry]

What's a Torx????????????

[Kevin]

What's a Torx????????????

Some examples here
http://www.tooled-up.com/MicroCategory. ... &MCID=1025

[MarkyB]

What's a Torx????????????

The generic name is hexalobular internal driving feature, does that help?

[polo2k]

Torx definately have their place and the "E" fittings all but eliminate stripped heads. A lot of modern vauxhalls use these exclusively and the only problems I ever encounter on these is the gebneral design, the fixing hardware woks FLAWLESSLY

if you find that torx always strip on you then try tapping them into the screw head before twisting and then slightly tighten it first.

even worse is the tripple square "M" sizes, first time they get dirty is the last time they work easily!

[mike.perry]

What's a Torx????????????-?[/quote]
The generic name is hexalobular internal driving feature, does that help?[/quote]
Nope!
I wondered what that strange socket in my tool box was

[frosty]

What's a Torx????????????

The generic name is hexalobular internal driving feature, does that help?

Funny name for an Allen key.