Stem on carbon steerer & torque wrenches??? (5nm or else??)
#27
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Note however that conventional micrometer torque wrenches are only accurate in the top 80% of their range.
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Simplistic dogma based on "% of full scale" spec. Do a calibration curve for one of these wrenches and you'll likely find it's most accurate somewhere other than near the max. For example, a 100 ft-lb wrench rated with an accuracy of %3 full of scale means that nowhere will it be more than 3 ft-lb off. It could be 3 ft-lb off at 100 ft-bl and only 0.5 ft-lb off at 30.
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Yeah, but sometimes 1 measurement is worth 1,000 guesses.
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Simplistic dogma based on "% of full scale" spec. Do a calibration curve for one of these wrenches and you'll likely find it's most accurate somewhere other than near the max. For example, a 100 ft-lb wrench rated with an accuracy of %3 full of scale means that nowhere will it be more than 3 ft-lb off. It could be 3 ft-lb off at 100 ft-bl and only 0.5 ft-lb off at 30.
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#32
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My CF Giant Defy Advanced has a CF seat post. And it's not a standard round post; rather, it's teardrop shaped. It kept slipping down so I kept tightening it up. Of course I didn't have a torque wrench that went that low.
The Cost: $250
New seat post: $200
Nice little torque wrench: $25
Tacx Carbon Prep: $25
Now I'm a great believer in torquing things properly and Tacx Carbon Prep. That stuff keeps things from slipping and binding without having to resort to excess tightening.
The Cost: $250
New seat post: $200
Nice little torque wrench: $25
Tacx Carbon Prep: $25
Now I'm a great believer in torquing things properly and Tacx Carbon Prep. That stuff keeps things from slipping and binding without having to resort to excess tightening.
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The 6nm is the max torque for the stem - they don't know what you are using it on. I think you will find that the fork manufacturer recommends 4nm.
#34
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My nice little torque wrench... $150.00
Precision is rated at 4% and is rated for 5000 clicks before re-calibration is required... in a shop environment this level of tool quality makes sense and ensures that torque values are set properly.
It comes in a padded steel tin which makes one mindful not to drop it and it is also compact enough and light enough to live in my shop apron.
(Ritchey sells a re-branded version of this for $100.00 more).
Precision is rated at 4% and is rated for 5000 clicks before re-calibration is required... in a shop environment this level of tool quality makes sense and ensures that torque values are set properly.
It comes in a padded steel tin which makes one mindful not to drop it and it is also compact enough and light enough to live in my shop apron.
(Ritchey sells a re-branded version of this for $100.00 more).
#35
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Thread Starter
FWIW, my UD CF seatpost has some interesting data that goes like this:
- Seatpost clamp itself says "5nm"
- Sticker on the UD CF seatpost itself says "Recommended torque 6.2nm"
- And then on that same sticker the line right below that says "Max torque 8nm"
That'll keep ya guessin, eh?
Again, I'd guess a 5nm would probably be plenty & certainly safe enough.....BUT.....how in the world somebody's gonna target 6.2nm is beyond me if none of these tools can be as accurate as such anyway...LOL
(FWIW, I recall my fitting guy at the LBS used the same exact "Torqkey" for every fastener on the stem/steerer/seapost and has been the fitter there for 2 years now)
(shrug)
#36
Banned
good thing about torque wrenches , the Newton/ Meter numbers have meaning, being on the scale of a 1/4" drive one..
So, we can put a number value on "how tight"
though some may be in inch / Oz pounds but you can find metric conversions online.
beam type cost less..
So, we can put a number value on "how tight"
though some may be in inch / Oz pounds but you can find metric conversions online.
beam type cost less..
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