Do you use a torque wrench or go by feel?
Discussion
There's an obvious gap between theory and practice when dealing with old machinery, which is that the manufacturer didn't list torque settings. That would originally be because he was waiting for someone to invent the concept, but when they had done he would doubtless include the values in the mechanics' training courses.
We were taught that the reason spanners have lengths that are greater for larger jaw size was that it gave the greater torque for a similar pull as you progress in nut/bolt size. I mention this as it shows some appreciation of the differing torque needs of different sized threads.
For those who worry about wheelnuts I offer the Rudge-Whitworth nut which is done up (and undone) with a hammer.
We were taught that the reason spanners have lengths that are greater for larger jaw size was that it gave the greater torque for a similar pull as you progress in nut/bolt size. I mention this as it shows some appreciation of the differing torque needs of different sized threads.
For those who worry about wheelnuts I offer the Rudge-Whitworth nut which is done up (and undone) with a hammer.
Allan L said:
We were taught that the reason spanners have lengths that are greater for larger jaw size was that it gave the greater torque for a similar pull as you progress in nut/bolt size.
Makes sense - I like to think that engineers don't design things with the intent that someone will need to give themselves an embolism to tighten fastenings with a tool of sensible length, or risk shearing heads off because the procedure asks for a T25 bit on a 3m breaker bar to do up an M5 aluminium screw (seriously Mercedes. Aluminium screws?! Who even MAKES aluminium screws?!)When I was young and couldn't afford frivolities like torque wrenches, I used to look at the Nm figure, look at the length of the tool I was using, work out roughly how many kg it should feel like I'm lifting when pulling up on it then use that as my torque setting. At the very least that would have put me in the right order of magnitude... Probably
On a few occasions I "calibrated" my arm first by lifting something of equivalent mass to remind myself how heavy it should feel.
A drawback is that the system only worked when pulling the bar towards me.
I use torque wrench on anything with multiple fixings - cam cover, sump, driveshafts etc
It’s not just the tightness of the bolt that matters it’s also the clamping force being equally distributed around the object, then you’ve got to think about expansion when it gets hot.
Tbh in all my years of walking around garages I can’t remember seeing a torque wrench's in use or lying about on a bench or in tool trays.
Imo - If you put a cam cover on without a torque wrench expect it it to leak.
It’s not just the tightness of the bolt that matters it’s also the clamping force being equally distributed around the object, then you’ve got to think about expansion when it gets hot.
Tbh in all my years of walking around garages I can’t remember seeing a torque wrench's in use or lying about on a bench or in tool trays.
Imo - If you put a cam cover on without a torque wrench expect it it to leak.
I used a torque wrench if its spark plugs or a alu bolt somewhere awkward that a) i REALLY dont want to come lose and b) i REALLY don't want it to snap as it'll be awkward to drill out without taking the engine out etc.
That said, i've done plugs with a torque wrench in the past where it clicks and you think, hmm, seems loose, i'll nip em up another quarter turn by hand
That said, i've done plugs with a torque wrench in the past where it clicks and you think, hmm, seems loose, i'll nip em up another quarter turn by hand
I usually just do engine and brakes. I've just had my front struts off and thought I'd use a torque wrench. Doing the strut to hub bolt felt too much to me, so just did everything bar the wheel nuts by hand.
Knowing how tight to do things up takes experience. That experience is gained the hard way, by stripping a few threads and snapping a few bolts.
Knowing how tight to do things up takes experience. That experience is gained the hard way, by stripping a few threads and snapping a few bolts.
105.4 said:
Torque wrench always.
The manufacturers would state torque settings if they were not required. My three torque wrench’s are used almost as much as my ratchets or my sockets.
They state torque settings because a lot of people who tighten things up have no sensitivity to how tight a fastener is. I'll use a torque wrench when I'm building an engine, but that is about it. I've found that a lot of the manufacturer's figures for steel in aluminium are optimistic anyway.The manufacturers would state torque settings if they were not required. My three torque wrench’s are used almost as much as my ratchets or my sockets.
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