Does anyone use torque wrenches?

[sevenfourate]

I use one regularly but never slacken off the tension when not in use. Apparently that's a bad thing?

Very ! Unlikely it’s (accurately) calibrated any more if it’s been left with tension on.

You can get re-calibrated though 😎

 

[figbat]

I have three. One big’un for the caravan wheel nuts and things like axle nuts, one medium for general purpose use where torque is important and a littl’un for little bike bolts, whether on carbon frames, stems or brake disc bolts. I’ll deploy as required rather than for every job.

 

[Regular.Cyclist]

I have three also. One has a fixed value for Speedplay cleats, one is 5Nm (which is pretty common on stems, seat post clamps, etc) and a third adjustable one normally set for the cassette lockring.

 

[ClichéGuevara]

Judging by the number being used according to this thread, it confirms the view that torque is cheap.

 

[Paulus]

I have only used a torque wrench once when replacing a head gasket on my Ford Anglia 45 years ago. It was borrowed from a mechanic mate of mine.
I have never used one on any of the bikes I have owned and worked on.

 

[TheDoctor]

Very ! Unlikely it’s (accurately) calibrated any more if it’s been left with tension on.

You can get re-calibrated though 😎

Easy to check the calibration using weights or a spring balance, and a ruler. Back to first principles.

 

[Cycleops]

I have only used a torque wrench once when replacing a head gasket on my Ford Anglia 45 years ago. It was borrowed from a mechanic mate of mine.
I have never used one on any of the bikes I have owned and worked on.

Same as me, almost forgotten, only it was a Morris Minor I was gas flowing the head and putting bigger valves on it. A crude affair with a thin metal coming from the head reading a scale on metal plate.

 

[fossyant]

Only on my GXP cranks as the spec is "f-off" tight. My hex keys aren't big enough.

 

[DRM]

Carbon frames and other components tend to be more sensitive to torque requirements than metal ones.

So I bought a torque wrench when I got my carbon framed bike, and I do use it.

You and me too, once a carbon frame is cracked, best case scenario is an expensive repair, worst case it's new frame time

 

[DRM]

I removed the bolts to cut them down, but one of the bolts was very resistant to being unscrewed; it fought me all the way out. I realized the 'bike mechanic' who installed them had cross-threaded it and forced it down all the way. $1700 for the bike and this was one of the two botch jobs they had done on it.

That's why you should ALWAYS initially screw things into a threaded hole with your fingers first, it's so easy to tell if the threads are crossing, and far easier to rectify

 

[presta]

Easy to check the calibration using weights or a spring balance, and a ruler. Back to first principles.

I have a Norbar wrench that's about 45 years old, but I don't store it with the spring compressed. I measured it about 12-15 years ago and it was within about 5-10% as I recall.

I removed the bolts to cut them down, but one of the bolts was very resistant to being unscrewed; it fought me all the way out. I realized the 'bike mechanic' who installed them had cross-threaded it and forced it down all the way.

I had the frame on my bike replaced under guarantee, and the LBS forced all the screws into threads on the new frame that were choked with paint, but fortunately it only knackered the screws and not the frame. Dawes don't call their paint Ardaznailz for nothing.

That's why you should ALWAYS initially screw things into a threaded hole with your fingers first, it's so easy to tell if the threads are crossing, and far easier to rectify

The excuse from the bike shop above was that they didn't have a tap to clear the threads, but perhaps it's better that they didn't, I dread to think the damage they could have done with that. When I did the job I was very careful to feel for the start of the tread with the tap in my fingers, and not the tap wrench.

Another common problem is people cutting a new thread each time they reassemble self-tapping screws instead of feeling for the existing thread. Domestic appliance repair men do it all the time.

 

[SpokeyDokey]

Mini torque wrench and 5Nm fixed wrench here.

Priceless for an otherwise avid over-tightener.

 

[TheDoctor]

@presta I expect within 5-10% is good enough, isn't it?
When I worked on instrumentation in the aerospace sector, we assumed 2% uncertainties, and that was with a calibration lab on-site.

 

[Gunk]

Been using one this morning, I’ve got three in total. This one is the one I use for bikes.

 

[fritz katzenjammer]

Since retiring from the real world I work part time at a factory owned Trek dealership, assembling bikes ranging in price from about 700 bucks up to about 18000.

We have a large number of quality torque wrenches covering varying ranges, they get used a lot.

Back when bikes were made of steel ( wonderful stuff that) you could torque the daylights out of your fasteners, secure in the knowledge that if something did let go it was usually the fastener or your cheap wrench (resulting in busted knuckles)

With the coming of aluminum and then carbon fibre reinforced plastics (lets call it what it is) its can be quite difficult to assure a critical fastener is tight enough without exceeding the ability of the supporting material to take the torque. We regularly get bikes through the shop which have been damaged because a timid home mechanic didn’t tighten something enough, leading to an assembly falling apart, or the bike is damaged because some ham-fisted type ( used to steel bikes I suppose) has over tightened something.

My favourite is carbon framed bikes ruined because somebody overdid the seat clamp and cracked the frame, love that one.

I currently own four torque wrenches and use them regularly... except on my steel bikes.