Torque wrench accuracy
#1 Torque wrench accuracy
I’ve had my torque wrench for many a year. It’s well used ( not really abused!)
It’s one of the basic type where the setting is achieved by twisting a marked barrel and pulling until it clicks.
I don’t really know how accurate it is. I know that this can be tested but that seems a faff and probably expensive. Does anyone have experience of these ? Do they go out of calibration?
Tim
It’s one of the basic type where the setting is achieved by twisting a marked barrel and pulling until it clicks.
I don’t really know how accurate it is. I know that this can be tested but that seems a faff and probably expensive. Does anyone have experience of these ? Do they go out of calibration?
Tim
Series 1 FHC purchased 40 years ago. Courted my wife in it.
Series 1 2+2 when the kids were small now sold.
Series 1.5 OTS in opalescent maroon, Californian car. My retirement present.
Series 1 2+2 when the kids were small now sold.
Series 1.5 OTS in opalescent maroon, Californian car. My retirement present.
Link: | |
BBcode: | |
HTML: | |
Hide post links |
#2 Re: Torque wrench accuracy
Hi Tim,
My approach would be to do nothing.
I have four, for different ranges, and some of them are 25 years old ; but they’re mechanical, and - contrary to some metallurgical misconceptions - steel does not go « off ».
I don’t believe there's anything on the Jag that is super critical, and as there are almost no torque figures given for so many of the fasteners that would be littered with specified torques on a modern car, my feeling is that the design was meant to fend for itself in the field.
And so it has proved.
An easy way to allay any fears you have for, say, head bolt torques, is to test your wrench against someone else’s - you can face one off against the other, as it were.
Cheaper than a test certificate anyway
My approach would be to do nothing.
I have four, for different ranges, and some of them are 25 years old ; but they’re mechanical, and - contrary to some metallurgical misconceptions - steel does not go « off ».
I don’t believe there's anything on the Jag that is super critical, and as there are almost no torque figures given for so many of the fasteners that would be littered with specified torques on a modern car, my feeling is that the design was meant to fend for itself in the field.
And so it has proved.
An easy way to allay any fears you have for, say, head bolt torques, is to test your wrench against someone else’s - you can face one off against the other, as it were.
Cheaper than a test certificate anyway
Rory
3.8 OTS S1 Opalescent Silver Grey - built May 28th 1962
3.8 OTS S1 Opalescent Silver Grey - built May 28th 1962
Link: | |
BBcode: | |
HTML: | |
Hide post links |
#3 Re: Torque wrench accuracy
Hi Tim...simple checks here https://www.onallcylinders.com/2021/12/ ... %20to%20go.
Steve
69 S2 2+2 (just sold) ..Realm C type replica, 1960 xk150fhc
69 S2 2+2 (just sold) ..Realm C type replica, 1960 xk150fhc
Link: | |
BBcode: | |
HTML: | |
Hide post links |
#4 Re: Torque wrench accuracy
Important advice in the above that I always follow - untension the wrench when finished.
I occasionally check the calibration using a spring balance pulling on the handle while the square drive is anchored in a vice. Simple and effective.
I occasionally check the calibration using a spring balance pulling on the handle while the square drive is anchored in a vice. Simple and effective.
Chris '67 S1 2+2
Link: | |
BBcode: | |
HTML: | |
Hide post links |
#5 Re: Torque wrench accuracy
Thanks guys,
I’m going to have a play with it later today. Will let you know how I get on.
Tim
I’m going to have a play with it later today. Will let you know how I get on.
Tim
Series 1 FHC purchased 40 years ago. Courted my wife in it.
Series 1 2+2 when the kids were small now sold.
Series 1.5 OTS in opalescent maroon, Californian car. My retirement present.
Series 1 2+2 when the kids were small now sold.
Series 1.5 OTS in opalescent maroon, Californian car. My retirement present.
Link: | |
BBcode: | |
HTML: | |
Hide post links |
-
- Posts: 1651
- Joined: Thu Feb 02, 2017 12:26 pm
- Location: Shropshire
#6 Re: Torque wrench accuracy
Presumably the spring balance is suitably calibrated?
Stuart
If you can't make it work, make it complicated!
'62 FHC - Nearing completion
'69 Daimler 420 Sovereign
'78 Land Rover Series 3 109
If you can't make it work, make it complicated!
'62 FHC - Nearing completion
'69 Daimler 420 Sovereign
'78 Land Rover Series 3 109
Link: | |
BBcode: | |
HTML: | |
Hide post links |
-
- Posts: 421
- Joined: Tue Dec 27, 2011 2:09 am
- Location: Omaha, NE area
#7 Re: Torque wrench accuracy
Touche
Steve
'65 S1 4.2 FHC (early)
'65 S1 4.2 FHC (early)
Link: | |
BBcode: | |
HTML: | |
Hide post links |
#8 Re: Torque wrench accuracy
"Presumably the spring balance is suitably calibrated"
Of course, by the 1kg weight I'd previously suspended from it.
And that 1kg weight was calibrated on the kitchen scales.
And the kitchen scales were calibrated using a 1 litre jug of water.
And the jug of water was calibrated by suspending it from the torque wrench at precisely 500mm from the centre of the 1/2" square drive, winding the tension down until it clicked.
Then with reference to the time of day, the atmospheric conditions, basic trigonometry adjusted by Euler's constant and the number I first thought of, I hoped that ateast one of the measurements was accurate.
Of course, by the 1kg weight I'd previously suspended from it.
And that 1kg weight was calibrated on the kitchen scales.
And the kitchen scales were calibrated using a 1 litre jug of water.
And the jug of water was calibrated by suspending it from the torque wrench at precisely 500mm from the centre of the 1/2" square drive, winding the tension down until it clicked.
Then with reference to the time of day, the atmospheric conditions, basic trigonometry adjusted by Euler's constant and the number I first thought of, I hoped that ateast one of the measurements was accurate.
Chris '67 S1 2+2
Link: | |
BBcode: | |
HTML: | |
Hide post links |
-
- Posts: 1651
- Joined: Thu Feb 02, 2017 12:26 pm
- Location: Shropshire
#9 Re: Torque wrench accuracy
Stuart
If you can't make it work, make it complicated!
'62 FHC - Nearing completion
'69 Daimler 420 Sovereign
'78 Land Rover Series 3 109
If you can't make it work, make it complicated!
'62 FHC - Nearing completion
'69 Daimler 420 Sovereign
'78 Land Rover Series 3 109
Link: | |
BBcode: | |
HTML: | |
Hide post links |
#10 Re: Torque wrench accuracy
Hi PM me I’ve got the bit of kit I think you need.
Peter.
Peter.
Peter {XKE V12HE efi}
XKRS
RR Phantom 3 1937 Sedanca de Ville.
XKRS
RR Phantom 3 1937 Sedanca de Ville.
Link: | |
BBcode: | |
HTML: | |
Hide post links |
#11 Re: Torque wrench accuracy
Don't be shy....share what it is
Steve
69 S2 2+2 (just sold) ..Realm C type replica, 1960 xk150fhc
69 S2 2+2 (just sold) ..Realm C type replica, 1960 xk150fhc
Link: | |
BBcode: | |
HTML: | |
Hide post links |
#12 Re: Torque wrench accuracy
Followed a few you tube videos on this. Checking calibration seems simple using weights at certain lengths along the shaft.
I reckon that mine is ok
I reckon that mine is ok
Series 1 FHC purchased 40 years ago. Courted my wife in it.
Series 1 2+2 when the kids were small now sold.
Series 1.5 OTS in opalescent maroon, Californian car. My retirement present.
Series 1 2+2 when the kids were small now sold.
Series 1.5 OTS in opalescent maroon, Californian car. My retirement present.
Link: | |
BBcode: | |
HTML: | |
Hide post links |