steve m
|
| posted on 29/1/13 at 11:10 PM |
|
|
reacalibrating a torque wrench
Im about to start a new engine build, and belive my torque wrench may not be correct
So is it a case of buying a new one ??
or can i have it recalibrated
regards
steve
|
|
|
|
|
SteveWalker
|
| posted on 29/1/13 at 11:16 PM |
|
|
Fasten the square drive in a vice and hang a known weight a known distance from the pivot?
|
|
|
britishtrident
|
| posted on 29/1/13 at 11:43 PM |
|
|
Ex-RAF Calibration gauges sometimes turn up second hand in tool stores -- but could you trust the calibration of the one.
Next easiest (but far from the most accurate) method is to hold the square drive in a vice and use a spring balance to measure the tangential force
on the handle and work out the moment of the force to get the torque exerted.
It is more accurate to to use a a known weight to pull the handle via a length string running over a pulley.
The other sanity check you can do is check it against another wrench.
It might be easier just to buy a new wrench.
The head bolts on most modern engines use angular tightening following an initial torquing, for these I have a a 3/8" drive wrench with a
low to medium torque range
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
|
|
|
steve m
|
| posted on 30/1/13 at 12:19 AM |
|
|
Thanks guys
BT
Its a xflow, so not modern!!
Steve
|
|
|
renetom
|
| posted on 30/1/13 at 08:47 AM |
|
|
wrench
Hi Steve
As Steve Walker said to check it
We have 2 , if you want to borrow one ,
no trouble, you have my No.
René
|
|
|
Stott
|
| posted on 30/1/13 at 09:08 AM |
|
|
Just take it for calibration.
Cromwell tools have a branch in Crawley and they calibrate wrenches, ring them for a price. I used to get mine done on a mobile van when I was
spannering.
|
|
|
Fatgadget
|
| posted on 30/1/13 at 06:51 PM |
|
|
Out of Idle interest,What the tolerances of torque figures provided by most manufactures?
|
|
|
Grimsdale
|
| posted on 30/1/13 at 07:42 PM |
|
|
cheap ones will be ±10%, i've just bought a norbar one that was advertised as ±3% but actually checked out at ±0.5%
|
|
|
