Torque Wrench for Crank Fixing Bolt?
09-15-20, 12:48 PM
#26
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I’ve got a length of flat bar with an 1/2” square hole cut at one end and a 3/8” hole at the other. I attach the bar to the torque wrench so that it protrudes horizontally, support the wrench on a table and hang what I consider a known weight off the other end of the bar and see what happens.
I don't believe that anyone has mentioned that flexible beam type wrenches do not need periodic calibration. Of course, you would need to know that the deflection graduations are accurate.
I’m reasonably confident that differences in thread friction have a greater influence on the torque I’m actually getting than the error in the tool as such.
Last edited by Moe Zhoost; 09-16-20 at 05:42 PM.
09-15-20, 02:14 PM
#27
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this is silly. professionals should use the right tool for the job, and they should be the most aware that their arms and wrists are no substitute for a torque wrench. I would not trust an over-confident mechanic who claimed such abilities. I worked in a bike shops wrenching on bikes for years, and the guys who are still in the industry are the ones who rely on the right tool for the job, not their pride.
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09-15-20, 07:40 PM
#28
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So why was the bottom bracket squeaking in the first place? Why did the shop professional think it advisable to remove and replace the bottom bracket?
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09-17-20, 08:59 PM
#29
Clark W. Griswold
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I recommend using a good quality torque wrench especially on parts like that. I know a lot of mechanics and many don't use torque that often and I don't love the idea because they could be off by a bit. The tools exist for a reason one should use them. Manufacturers aren't putting 5nm or 12-14nm on parts just for a lark.
If you use it often probably not a bad idea to have it calibrated regularly.
If you use it often probably not a bad idea to have it calibrated regularly.
09-18-20, 05:27 AM
#30
Randomhead
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I have had extremely poor luck with Shimano cranks that aren't torqued using a torque wrench. Sram cranks aren't so bad since the torques are so much higher.
