Why do Germans love Torx so much?

[FSrepair&fabrication]

Its one of those things that looks like a good idea on paper but it the real world doesnt do so well. It beats philips any day of the week but for anything over say 30 or so ft/lbs can get nasty once corrosion sets in. With my luck the last gorilla to work on it used a 3ft breaker bar to tighten it and stripped it out for me already.

 

[American Locomotive]

You not getting my point, when you look at that head size to the shank size thus the potential torque value of that fixing, the torx offers low max value and has potential weak tooling to fastener size too .

It great in right scenario and far nicer socket drive than hex and phillips but has lot of potential drive condition issues not just from salt city rust that can reduce torx socket performance/usability far too easily .

Main issue is it used in many applications that truly don't need it and also plenty room fit standard hex head or JIS fasteners .

Head size to shank size is not meaningful. An m6 grade 12.9 bolt is rated to be tightened to a certain torque. That bolt according to DIN standards will either have a 10mm hex head or a Torx T30. The T30 is much, much smaller but will reliable achieve the same torque. A 5mm hex would be the closest hex size to a T30, and is not capable of handling that torque.

 

[Spacey_G]

American Locomotive - The numbers suggest that the 5mm hex is plenty capable of handling the rated torque for a grade 12.9 M6 bolt. It seems to be in the same ballpark as the T30 torx.

Max typical tightening torque for the bolt is 19.9 N-m (ref. 1)
Torque rating for a 5mm hex bit - 35 N-m (ref. 2)
Torque rating for a T30 Torx bit - 31 N-m (ref. 3) or 31-37 N-m (ref. 4)

References:
1. https://www.engineeringtoolbox.com/metric-bolts-maximum-torque-d_2054.html
2. https://www1.mscdirect.com/PDF/FASTENERS/HexKeys.pdf
3. https://www.newmantools.com/tech/torxspecs.htm
4. https://www.wihatools.com/torx-sizes

 

[Mr_B]

Head size to shank size is not meaningful. An m6 grade 12.9 bolt is rated to be tightened to a certain torque. That bolt according to DIN standards will either have a 10mm hex head or a Torx T30. The T30 is much, much smaller but will reliable achieve the same torque. A 5mm hex would be the closest hex size to a T30, and is not capable of handling that torque.

head size and more importantly diameter of drive to diameter of fixing shank is very meaningful on applied torque potential at the drive hence why so many have issues with torx and high rate of tool damage .

 

[Olafur]

Head size to shank size is not meaningful. An m6 grade 12.9 bolt is rated to be tightened to a certain torque. That bolt according to DIN standards will either have a 10mm hex head or a Torx T30. The T30 is much, much smaller but will reliable achieve the same torque. A 5mm hex would be the closest hex size to a T30, and is not capable of handling that torque.

I don't get this comparison. 6mm bolt with 5mm hex head, well, It doesn't have a head. outside circle diameter for 5mm hex is 5,77.. mm - so less than the shank. Not a real world example except perhaps for set screws.

A quick search didn't find a 6mm fastener with smaller head than 10mm in diameter, many for I-torx are actually even bigger. So at least 8mm socket could be used. Perhaps not available but possible.

 

[ngk22r]

Head size to shank size is not meaningful. An m6 grade 12.9 bolt is rated to be tightened to a certain torque. That bolt according to DIN standards will either have a 10mm hex head or a Torx T30. The T30 is much, much smaller but will reliable achieve the same torque. A 5mm hex would be the closest hex size to a T30, and is not capable of handling that torque.

How well will that T30 torx bit do on a fastener in limited space where a 1/4 flex head needs to be used. No room to stick your hand in to apply equal pressure and support.

 

[American Locomotive]

American Locomotive - The numbers suggest that the 5mm hex is plenty capable of handling the rated torque for a grade 12.9 M6 bolt. It seems to be in the same ballpark as the T30 torx.

Max typical tightening torque for the bolt is 19.9 N-m (ref. 1)
Torque rating for a 5mm hex bit - 35 N-m (ref. 2)
Torque rating for a T30 Torx bit - 31 N-m (ref. 3) or 31-37 N-m (ref. 4)

References:
1. https://www.engineeringtoolbox.com/metric-bolts-maximum-torque-d_2054.html
2. https://www1.mscdirect.com/PDF/FASTENERS/HexKeys.pdf
3. https://www.newmantools.com/tech/torxspecs.htm
4. https://www.wihatools.com/torx-sizes

Look up Torx Plus T30 - they're rated for well over 45nm minimum strength. It's important to keep in mind that Torx and Torx Plus can do those high torque numbers all day long without issue. This is important for assembly lines where one bit will insert thousands of fastenters. It's also important for screws that require frequent removal. Hex heads (socket or otherwise) wear fast at high torques.

head size and more importantly diameter of drive to diameter of fixing shank is very meaningful on applied torque potential at the drive hence why so many have issues with torx and high rate of tool damage .

You need to look up fastener drive angle. Torx (and Torx Plus) are used because the 15 and 0 degree drive angles allow for higher torques at greatly reduced tool wear. It's why it's used frequently in the automotive world.

I don't get this comparison. 6mm bolt with 5mm hex head, well, It doesn't have a head. outside circle diameter for 5mm hex is 5,77.. mm - so less than the shank. Not a real world example except perhaps for set screws.

A quick search didn't find a 6mm fastener with smaller head than 10mm in diameter, many for I-torx are actually even bigger. So at least 8mm socket could be used. Perhaps not available but possible.

It's an example, you don't have to take it literally. A 10mm hex head fastener with matching socket will take up much more space than a T30 torx head screw would.

 

[JR 42]

So, if I understand this correctly...

On paper, and in clean or high- use circumstances, Torx fasteners are more efficient for rapid assembly, especially considering tooling life, and have smaller and lighter heads.

In practice, on cars, say, Torx bolts **** because you have less mechanical advantage due to the reduced diameter of a Torx bit compared to a hex head.

I was going to ask upthread, but I think mbshop already answered - has anyone broken a Torx- head bolt on a car? I'd bet most folks have snapped a hex bolt, and a bunch have broken Torx bits, but... ?

 

[ngk22r]

It's an example, you don't have to take it literally. A 10mm hex head fastener with matching socket will take up much more space than a T30 torx head screw would.

While this part is true, if you refer to my previous post the torx bit sockets do not work out well.

So, if I understand this correctly...

On paper, and in clean or high- use circumstances, Torx fasteners are more efficient for rapid assembly, especially considering tooling life, and have smaller and lighter heads.

In practice, on cars, say, Torx bolts **** because you have less mechanical advantage due to the reduced diameter of a Torx bit compared to a hex head.

I was going to ask upthread, but I think mbshop already answered - has anyone broken a Torx- head bolt on a car? I'd bet most folks have snapped a hex bolt, and a bunch have broken Torx bits, but... ?

Does stripping out a torx head bolt count?

 

[JR 42]

Haha, nope. Lots of broken hex bolts, lots of broken Torx bits, just wondering if anyone's broken the threaded portion of a Torx bolt trying to get it loose.

 

[techieman33]

So, if I understand this correctly...

On paper, and in clean or high- use circumstances, Torx fasteners are more efficient for rapid assembly, especially considering tooling life, and have smaller and lighter heads.

In practice, on cars, say, Torx bolts **** because you have less mechanical advantage due to the reduced diameter of a Torx bit compared to a hex head.

I was going to ask upthread, but I think mbshop already answered - has anyone broken a Torx- head bolt on a car? I'd bet most folks have snapped a hex bolt, and a bunch have broken Torx bits, but... ?

I haven't had a head break off, but I've had plenty strip out, which might as well be the same thing. My thought is that there is more surface are and smaller bits of metal on the head for corosion to eat into than the rest of the bolt. So that ends up being the weakest point, and where the failure will occur. At least with a hex head if it starts to strip out you have a chance to get in there with a specialty socket and still remove the bolt. But when a torx strips out your done for.

 

[Mr_B]

I bench tested some torx bolts to see if can break the bolt and I coudn't.
drive or tool fails first as torque load of the small drive on larger fixings is always a bit low .
I also find claims of drive angle ability on torx poorer performing in real world use, once you add drive angle the torque handling is further reduced and cam out is easily achieved .
They great drive on light fixings and machine screws, lovely to use in construction on screws but not for much else .
French and euro ford used them on brake and suspension bolts for some years and it was hated even by dealers in early years of servicing as proved so troublesome .
Peugeot have some very good examples of where and when not to use them ...

 

[Bagherra]

To me, it's a false advantage. It's like saying Syphilis is good, because HIV is worse. I'd rather have a clean bill of health with my 6 point fasteners.

 

[byoungblood]

torx, allen etc has no place on high torque, corrosion prone auto application.
I got no idea why the idiots use them, they more expensive and a total **** deal with in later life repair work .
They don't even have the sense make engagement depth better to give half a chance of it working .
Add to mix lower quality fixings on new junk the issues with these fixings in automotive use just get worse .

That greatly depends on the fastener used. Ford used some really shallow Torx screws to hold the intake cover plate on the old pushrod 5.0 EFI engine. You could almost count on snapping off a bit in one of those because the engagement between the fastener and tool was very small and you dealt with galvanic corrosion between the steel screw and aluminium manifold. Right idea, but probably fell prey to bean counters trying to save a quarter of a cent on the fasteners.

TJ Jeeps make extensive use of Torx bolts on the front and rear bumpers, but they have deep recesses and use a T60 socket, so even if they're fairly rusty, even a fairly cheap socket will remove them.

 

[Mr_B]

That greatly depends on the fastener used. Ford used some really shallow Torx screws to hold the intake cover plate on the old pushrod 5.0 EFI engine. You could almost count on snapping off a bit in one of those because the engagement between the fastener and tool was very small and you dealt with galvanic corrosion between the steel screw and aluminium manifold. Right idea, but probably fell prey to bean counters trying to save a quarter of a cent on the fasteners.

TJ Jeeps make extensive use of Torx bolts on the front and rear bumpers, but they have deep recesses and use a T60 socket, so even if they're fairly rusty, even a fairly cheap socket will remove them.

Yes deep and large size on quality alloy bolt fairly decent .
Why the standard was not deeper recess I do not know ! cent saving one would assume .

 

[finn]

My 2000 Mountaineer is the same. It has the 302 so the drivetrain is mostly standard with a little metric mixed in. Then the rest is mostly metric, but you find some standard mixed in at times.

The 302 in your car goes back to 1962, fast approaching sixty years old.

Ford converted to metric in about 1974, with the introduction of the 2.3 Lima engine, for new powertrain designs.

Legacy products eventually disappear.

As others have stated, Torx is there because of tool life in a production environment and weight savings. Those two attributes overrule all others in engineering objectives for high volume automotive production.

 

[byoungblood]

Yes deep and large size on quality alloy bolt fairly decent .
Why the standard was not deeper recess I do not know ! cent saving one would assume .

That's exactly it. To an individual, spending one cent less on 4 fasteners seems silly. But consider a manufacturer buying hundreds of thousands, if not millions of those fasteners, and then the cost adds up rather quickly. Not to mention their primary concern of the suitability of the fastener mainly extends to assembly and maybe warranty if it is a fastener that is likely to be removed frequently or likely to corrode and call for replacement. Then spending the extra 1 cent makes sense if it saves having to pay $2 for replacement fastener(s) down the road.

 

[cherrybomb]

It seems the Germans have always been engineering new mechanicals.Somethings have worked out,but variables like hard accessibility , corrosion,over torqued fasteners ,a guy has to be sure his install and removal tools are of excellent quality,and not worn.Thats sometimes where problems sometimes arise.It seems that damage removal tools,eze outs,left hand drill bits and something that I've studyied,Sock It Out ,a product that you hammer in the damaged fastener,if you don't have a back up plan,wrenching on these so called better fasteners can be extremely frustrating and time wasting.

 

[Mr_B]

That's exactly it. To an individual, spending one cent less on 4 fasteners seems silly. But consider a manufacturer buying hundreds of thousands, if not millions of those fasteners, and then the cost adds up rather quickly. Not to mention their primary concern of the suitability of the fastener mainly extends to assembly and maybe warranty if it is a fastener that is likely to be removed frequently or likely to corrode and call for replacement. Then spending the extra 1 cent makes sense if it saves having to pay $2 for replacement fastener(s) down the road.

And the cent saving mentality and engineering as minimal as possible really pays off !

 

[Spacey_G]

Mr. B - I keep seeing the term 'fixings' in your posts. Can you explain what you mean by that? Is that like the side dishes at Thanksgiving dinner?

 

[lightning struck]

Love torx!!

 

[Sine Swept]

When you can't get that bolt out, or would rather pay than deal with it yourself, then it's just more money for someone.

If it was easy everyone would be doing it.

 

[Hermann-the-german]

Go to wikipedia and search for TORX.
There are a number of ADVANTAGES of Torx over allen. Once you read the descriptions you will learn to LOVE Torx. ...

More than that, you will learn, that Torx was invented 1967 by Camcar Textron. Working with handtools, I prefer Allen over Torx. But when comes to driving screws into wood with high to torque, Torx is way better than Phillips, Pozidriv or other outdated profiles.

Lately, I came across this profile at the brakes of my car. Have you ever seen it before? Very uncommon even in Germany.

 

[American Locomotive]

I bench tested some torx bolts to see if can break the bolt and I coudn't.
drive or tool fails first as torque load of the small drive on larger fixings is always a bit low .
I also find claims of drive angle ability on torx poorer performing in real world use, once you add drive angle the torque handling is further reduced and cam out is easily achieved .
They great drive on light fixings and machine screws, lovely to use in construction on screws but not for much else .
French and euro ford used them on brake and suspension bolts for some years and it was hated even by dealers in early years of servicing as proved so troublesome .
Peugeot have some very good examples of where and when not to use them ...

The "drive angle" in my posts refers to the angle at which the driver contacts the fastener edges. Hex sockets have a 60 degree drive angle, which promotes smearing and deformation of the head and tool. This really limits the amount of torque you can reliably (and repeatedly) apply to a fastener without damage.

Torx has a 15 degree drive angle (Torx Plus has a 0 degree), which means nearly all of the force gets applied tangentially to the axis of rotation. This radically improves tool life, and allows more torque at a given head size.

Your claims saying they're "not good for much else" are based solely on rusty undercarriage screws. Like I've said many times, where you need features like high-torque at a given size, high tool life, and high fastener life - Torx is where it's at all. I've worked in industries where they replaced all of the fasteners on their tool with Torx Plus in place of standard hex head cap screws. Stripped and damaged screws basically disappeared.

 

[mr.lemons]

Lately, I came across this profile at the brakes of my car. Have you ever seen it before? Very uncommon even in Germany.

Ribe? I also recently found I needed a Ribe bit but on a Vauxhall camshaft. Think they are more often found as head bolts.

 

[Spacey_G]

American Locomotive - I have an application using 2-56 screws torqued to 55 in-oz. We're currently using 18-8 stainless button heads with a .050" hex drive and they're terrible. If we don't replace them every time they're removed, they strip out.

I can change these to either button heads with an IP6 torx plus drive or normal socket head cap screws with a 5/64" hex drive. Which would be better, the similar sized torx plus or the larger hex?

 

[bushmechanic]

Torx is outstanding.

More of the tool is used, more of the fastener is used, and it's much easier to get a positive interface between the two.

When people go on about rusty hardware under cars, they are forgetting that they're not trying to turn the best Torx has to offer, and forgetting that the same issues happen with other hardware.

You can indeed get in there and McGyver a messed up Torx head out of a rusty component. It's just a different process than doing it for a jacked up hex head.

External, internal... It's a better solution within it's own specifications.

I'd be surprised if anyone preferred "Allen" solutions. Those things have always been cheese. What I usually see are frustrations simply because people don't run into them often and have to go digging and learning new things.

That's something time will correct, as it slowly has done for metric.

 

[fsae0607]

There should be a rule that you’re only allowed a limited number of sizes and types of fasteners on a project.

I’m working on my ‘83 Mustang which was build during the change to metric.
I’ve probably used every wrench and socket I own on this project.
“Common” on the Mustang is:
7mm, 11mm, 15mm, 17mm, 18mm, 1/4, 3/8, 1/2, 5/8, 11/16, 3/4, 13/16, 15/16,
Torx and Phillips.

The brake caliber bolts and the rear shock mounts are torx.

There are brake lines that are inverted flare on one end and bubble flare on the other.

The bell housing bolts are 5/8 head and the transmission to bell housing bolts are 15mm head. The driveshaft bolts I can only get with a 12point 12mm wrench.

You have to really pay attention and not assume something is metric or not, very easy to mistake a 9/16 for 15mm and round it off.



Sent from my iPhone using Tapatalk

Lmao GM G-Bodies are notorious for that, too. I used to have a '79 Cutlass and would empty my toolbox working on it.

 

[American Locomotive]

American Locomotive - I have an application using 2-56 screws torqued to 55 in-oz. We're currently using 18-8 stainless button heads with a .050" hex drive and they're terrible. If we don't replace them every time they're removed, they strip out.

I can change these to either button heads with an IP6 torx plus drive or normal socket head cap screws with a 5/64" hex drive. Which would be better, the similar sized torx plus or the larger hex?

From what I've seen in industry, almost anything with screws that small that need to be removed often are using Torx Plus these days.

Where I've worked, they really liked using the Wiha TorqueVario T-Handles and TorqueFix wing drivers for the tiny Torx Plus bits. Very, very rarely were screws stripped.

 

[F124C]

Lately, I came across this profile at the brakes of my car. Have you ever seen it before? Very uncommon even in Germany.

Ribe? I also recently found I needed a Ribe bit but on a Vauxhall camshaft. Think they are more often found as head bolts.

Yes, looks like RIBE, also used in some locations on Fiat/Alfa Romeo etc. over the past 20? years. Wouldn't be surprised if FCA introduced it in the USA
(if they haven't already).

 

[Mr_B]

The "drive angle" in my posts refers to the angle at which the driver contacts the fastener edges. Hex sockets have a 60 degree drive angle, which promotes smearing and deformation of the head and tool. This really limits the amount of torque you can reliably (and repeatedly) apply to a fastener without damage.

Torx has a 15 degree drive angle (Torx Plus has a 0 degree), which means nearly all of the force gets applied tangentially to the axis of rotation. This radically improves tool life, and allows more torque at a given head size.

Your claims saying they're "not good for much else" are based solely on rusty undercarriage screws. Like I've said many times, where you need features like high-torque at a given size, high tool life, and high fastener life - Torx is where it's at all. I've worked in industries where they replaced all of the fasteners on their tool with Torx Plus in place of standard hex head cap screws. Stripped and damaged screws basically disappeared.

It purely a system for assembly benefit over anything else.
On machine screws and screws it can be superb, on anything subject to coatings, dirt, chemicals, thread locking, fastener head abrasion it a PITA .
Sockets for the size of fixing always have a low potential max torque handling, the external torx is far better torque handling and better choice on larger fixings and still has smaller head/tool vs standard hex .
Main problem with it is gets used with poor quality fasteners and in areas that truly have no need for it .

 

[Hammer1963]

An easy question to answer. Torx is superior to Phillips, slotted and most pre 1960's drive systems. Advanced drive technology was not designed to make someone more money by tool sales as some have stated. That's an absurd statement. It's purpose is to allow for increased torque. smaller drive heads and increased production. Same reason bias ply tires are seldom used. Technology ... It's a great thing!

 

[AusGlenno]

Most people would look at you with a blank stare if you told them something was a meter long, but say a foot long and people understand. Its ingrained, they raised multiple generations and taught them in standard. Meanwhile everyone else went to metric and we refused (mostly).

That is not a very good answer. Australia switched. I'm sure 30-40 years ago you would have got a blank look from people when you said 1 meter or 1 kg. BUT people adapted. Having operated US branded helicopters for 20 years I'm pretty happy with my grasp of the outdated measurement system the yanks still use. Doesn't mean it is good.

But the point of my post was it isn't just the Germans or Euros that make people have to keep extra tools. If I buy anything American I need to by imperial (or equivalent name) tooling.

 

[Engineer61]

A lot of advantages for Torx have been stated, and the history and who invented Torx have been put forth, but the reason Torx was invented is for automated assembly - i.e. the robots that auto manufacturers were looking to start using. Internal drive simply lets robotic system auto-align in putting in the fasteners and phillips heads, allen heads etc were too easy to strip out or (allen heads) didn't do a good job of auto-aligning the fastener and the bit. Torx was invented to solve those problems and it did.
Engineers use Torx more and more because more and more assembly is done using automated/robotic machinery.

 

[finn]

Most people would look at you with a blank stare if you told them something was a meter long, but say a foot long and people understand. Its ingrained, they raised multiple generations and taught them in standard. Meanwhile everyone else went to metric and we refused (mostly).

People aren’t that stupid, are they?

I moved to Europe, where everything is metric. It took me about a week to adapt to the system of weights and measures.

When I moved back here, it took about the same time to readapt to our antiquated system.

I still have difficulty sometimes with 32nds and 64ths of an inch, though.

 

[CJM8515]

People aren’t that stupid, are they?



I moved to Europe, where everything is metric. It took me about a week to adapt to the system of weights and measures.



When I moved back here, it took about the same time to readapt to our antiquated system.



I still have difficulty sometimes with 32nds and 64ths of an inch, though.

You underestimate just how stupid your average fellow man is.

 

[icthruu74]

I just did brakes on a late ‘90’s Buick that had Etorx bolts holding the rear wheel cylinders on. I only have Etorx sockets and there wasn’t enough room to get a socket and ratchet on them. Ended up grinding one of them off and the other was able to use a HF socket clamped with a vice grip. I’m seeing a set of Etorx wrenches in my future.

 

[clown]

I was searching for a torx and hex bit socket set and this thread came up in the search.

I have an older VW and an older MB, the MB is consistent with using e-torx, but the VW uses a little bit of everything for fasteners. I'm not a mechanic by trade, but have decent amount of experience working on cars/airplanes, and I just don't see a need to use all these different type of fastener heads in most applications.

IMHO this practice has had the greatest effect on killing the Western world's tooling industry.

For example, if most car manufacturers used traditional 6 point hex heads or e-torx heads, the DIYer, or even the independent mechanic could buy a quality set of sockets/wrenches and be done with it.

However, if you need torx/hex/e-torx/6 point hex, 12 point, XZN, security torx, Robinson, most DIYers/independent mechanics aren't going to spend the cash to buy quality items that are hardly ever used.

I understand that this is what the car manufacturers want, like...oh, I don't have that tool to do the job, so I'll take it to the shop, or buy a Chinese tool to get the job done. Then that tool sits in the garage getting rusted/collecting dust for the next 6-7 years.

I know I'm reviving an old thread, but just wanted to add my .02 cents.

This is an awesome forum, and I've learned a lot from reading the posts on here.

 

[seber]

Torx has a lot of advantages but I've been drilling out the damned things on my Sprinter almost since day one. They are absolute horror when they rust. As far a s German engineering. Meh. We bought some German machinery in my job as production engineer. Every time I tried to put German stuff to work it had to be reengineered to make it work. I was actually told by one of the people who designed that stuff. "We make it perfect. You need to adapt your design to our equipment." That's not how the real world works.

 

[RKA]

I was searching for a torx and hex bit socket set and this thread came up in the search.

I have an older VW and an older MB, the MB is consistent with using e-torx, but the VW uses a little bit of everything for fasteners. I'm not a mechanic by trade, but have decent amount of experience working on cars/airplanes, and I just don't see a need to use all these different type of fastener heads in most applications.

IMHO this practice has had the greatest effect on killing the Western world's tooling industry.

For example, if most car manufacturers used traditional 6 point hex heads or e-torx heads, the DIYer, or even the independent mechanic could buy a quality set of sockets/wrenches and be done with it.

However, if you need torx/hex/e-torx/6 point hex, 12 point, XZN, security torx, Robinson, most DIYers/independent mechanics aren't going to spend the cash to buy quality items that are hardly ever used.

I understand that this is what the car manufacturers want, like...oh, I don't have that tool to do the job, so I'll take it to the shop, or buy a Chinese tool to get the job done. Then that tool sits in the garage getting rusted/collecting dust for the next 6-7 years.

I know I'm reviving an old thread, but just wanted to add my .02 cents.

This is an awesome forum, and I've learned a lot from reading the posts on here.

I feel your pain. 20 years with Audi's and after the existing one dies, it may be a long time before I go back (for other reasons). What makes it worse is you need a short and a long bit socket for each fastener type and in some limited cases I've even needed a mid length to squeeze into all the tight quarters. The hex, that was easy, cut the long down to size. With the XZN, I went scouring the internet and local auto parts stores last year while the car sat up on jackstands because of 2 stupid bolts.

If you could give me five minutes in a cage with a VW engineer...! One can only dream.