TiHabanero

Installed a G2R disc brake yesterday and everything was Torx fitted. This got me thinking what is this fascination with Torx fittings? The bleed ports, which are super low torque fittings and clamp bolts are Torx. Why? What problem does this solve? Or is it a solution looking for a problem? Or is this just some twisted attempt to change the long standing industry standard of using recessed hex fittings or a really twisted way to increase tool sales or inconvenience home mechanics?

dsbrantjr

Torx drive is more resistant to "cam-out" than slotted or Phillips heads, and more resistant to stripping than hex drive. https://en.wikipedia.org/wiki/Torx
I suspect that they tolerate use with worn drivers better than hex, Torx kind of makes sense when reading the numerous posts on this forum asking for help with stripped-out hex drive fasteners.

Trevtassie

Automated assembly is easier with torx.

andrewclaus

I'm old enough to remember thinking the same thing when Phillips heads started showing up so much in the construction industry.

Amt0571

Because it's better. I can't count the amount of times I have rounded an hex bolt trying to loosen something that has been assembled for a long time.

For a home mechanic it's way worse having something stuck and the hex becoming rounded than having to buy some torx bits, which are not all that expensive in the first place.

Andrew R Stewart 

I'll add that Torx allows a smaller bolt, or a smaller wrench fitting which then allows a smaller bolt, to do the job. Also a softer one, as in Al instead of steel. Andy

HillRider

Allen (aka hex) fasteners are quite sensitive to being damaged by cheap and/or worn hex keys, particularly in the smaller sizes. Torx are stronger and more tolerant of wear and I also much prefer them to allen bolts.

woodcraft

They work pretty well, but I share your frustration toward the proliferation of driver patterns.

With Torx in particular, you can't really tell the difference visually between a T15 and a T20, or between T20 and T25,
and the same fastener in different lengths might take different driver sizes.

I regularly deal with, and often carry in my pocket, T15, T20, T25, T30, PH2, PH3, S1, S2, S3, square/phillips combo, 1/4", 5/16' nut drivers, SAE and metric allen key sets, and 1/4" and 3/16" slotted screwdrivers.

August West

I wasn't aware there was fascination with Torx fasteners in the bike industry. The only Torx fasteners I've run across in wrenching on my bikes were the chainring fixing screws securing the chainrings to the crank on Shimano cranksets. But I find them superior to hex screws in just about every application I used them.

DrIsotope

As a guy who's driven a few thousand pounds of decking screws, I can say that Torx is the way to go. Bikes should be all Torx. I mean sure, I curse at a Ford I'm trying to do the brakes on because it needs something bizarre like a T47, but they pretty much don't slip or strip.

Darth Lefty 

As a guy who built his own deck one time, I agree!

you’re also never going to round out the Torx by using the 3/16 instead of a 5 mm because it’s the only one you can find right now

They are all over BMW motorcycles as well.

I am camping right now, so I think to add that our travel trailer is built almost entirely with square head screws. They are basically Phillips without the flanges. They seem to work pretty well, although I’d still rather have the torx

DrIsotope

I would put Torx all the way at the top. Right above Robertson/Doublesquare, which are above hex. I would rather pound and pull nails than deal with slotted, and Phillips is one of the greatest scams ever perpetrated against mankind.

rydabent

That isnt the half of it. As an IBM service rep that started in '61 and worked until 2008 look what I had to work with.

Early IBM machines has standard allen wrenches. Then in the series the Co went to 4 flute bristo, 6 flute bristo, metric allen, and then torx. I had to carry a series of all sizes of all of them depending on the age of the machines. They all did the same thing.

Right now cyclist have to carry both metric allens and torx to be prepared on the road.

Iride01 

I wasn't aware of a fascination either.

I've been wondering why the bike industry is still using Philips for tiny adjustment screw so long. Torx is definitely the way to go for small screws. Or even large screws too.

I even found some small torx screws to match the size and threading of the little tiny Philips screws they use in my Garmin HR pod. Makes getting them in and out so much easier. Of course being Torx, you have to be careful not to over tighten since they don't cam out.

A set of Torx driver points doesn't cost much at all.

Clyde1820

^ This.

Always thought two things:

1. Torx is better at avoiding "cam-out" (fouling the heads' threads) than Phillips.

2. Mfrs, generally speaking, seem to under-spec the size of the bolt (or screw) for the function. Trying to minimize costs, I'd bet.

Much of the "stripping" of the heads could be alleviated by having larger/deeper-headed Torx screws. Always can be less likely to strip things with better, hardened tools.

That said, I've still seen stripping, and occasional breaking, of a bolt/screw head ... even with Torx.

Prefer them, myself, I suppose, all things considered. So long as it's hardened bolts/screws, sufficiently beefy for the application, with a good tool, and so long as precautions are taken with anti-seize on the bolt/screw itself.

Chinghis

Thanks, this is kind of a fascinating thread. I've only ever thought of Torx screws as a tech thing, didn't realize they were showing up on bikes. Also never realized their advantages.

dsbrantjr

Phillips was designed to cam out BITD before torque limiting drivers were common; they would cam out before breaking the fastener/stripping the threads.

fietsbob

The rebuild of my porch/deck around my house used all Torx flat head wood screws..
battery powered drivers is a staple of the construction biz these days..






..

robertorolfo

I've mostly dealt with Campagnolo torx stuff, which doesn't have a great reputation, but in my experience it strips easier than hex/allen.

You say that like it's a good thing...

Darth Lefty 

I understand why they did it. BMW don’t focus on making their bikes convenient for a shade tree mechanic. They often use three or four parts where a Kawasaki might have one, as well, and they have more sensors and computers. But you can always tell that there’s a reason they did it that way, and the result is better. The expense is expensiveness.

tyrion

Judging by the comments in this thread, it seems everything should be torx. Maybe Allen Company had better marketing than Torx Company, and convinced the world to use an inferior product.

Iride01 

I always love the conspiracy theory folks that think things are done to put a hardship on DIY'ers.

Wait till you learn what a safety torx is! (also known as a security torx)

There are inexpensive driver bits for them too. And they work in a regular torx socket.

Riveting

Then what is the deal with the square hole screws used for decks, why are those used instead of Torx?

Iride01 

This soon to be eight year old article popped up: https://www.slowtwitch.com/Tech/Bolt...Win__3170.html

TiHabanero

I have used square drive screws for decks and cabinetry and can say they take some serious torque loads without rounding out of the head. I assume that is the reason for using them. The head can also be made very small in relation to the screw shaft size.

One issue I have come into with Torx was the bolts securing a rotor to a hub. Bent the shaft of the driver bit, and rounded out the screw heads. Not sure any other screw type would have made a difference, but for sure Torx did not offer any advantage with those 6 bolts.