Torque Wrench Calibration question

I have various Torque wrenches, that are all calibrated in the clockwise manner only. they do work counter clockwise, our call outs are for tightening only.
Question was brought to my attention about lossening bolts counter clockwise messing up the calibration of my torque wrench. is this possible?
we have clicker type, digital, dial,etc.

Re: Torque wrench question

Mmmm, I'm thinking the person who made that comment doesn't know much about torque wrenches...

Re: Torque wrench question

My 2 cents. With a clicker torque wrench I do not know. However with the dial and the digital torque wrench it should not make any difference which way it is turned.

Re: Torque wrench question

I was always taught to only break out the torque wrench when it came time to put the final turns on whatever is being torqued. A torque wrench, a good one is at least $150 and how many places have the ability to calibrate one in house, I say why risk it.

Re: Torque wrench question

Every torque wrench I have used (or seen used) can be used to measure installation torque or break away-torque on both right and left handed threads so the calibration should be appropriate for its use. However, I consider a torque wrench to be a measuring tool so I guess I agree with qualitypirate regarding its use.

Re: Torque wrench question

I have not seen the clicker type that function both directions but that does not mean they don't exist. These do need to only be used for tightening and not loosening. If you have one that functions both ways as some dial types do then it should be for a reverse thread that tightens counter clockwise. Added force in removing a tight nut could affect the accuracy.

Re: Torque wrench question

The clicker wrench I use in my garage at home (cheapo Craftsman) has a ratchet head.....works either way. I also have an even cheaper pointer style that works either way.

Left hand torque wrenches are almost as common as any other left hand wrench.

That said, it might be wise to refer to them as torque gages rather than torque wrenches. That might help keep them from be misused.

Re: Torque wrench question

BadgerMan said:

The clicker wrench I use in my garage at home (cheapo Craftsman) has a ratchet head.....works either way. I also have an even cheaper pointer style that works either way.

Left hand torque wrenches are almost as common as any other left hand wrench.

That said, it might be wise to refer to them as torque gages rather than torque wrenches. That might help keep them from be misused.

Click to expand...

At the risk of opening up a previously well beaten thread, torque wrenches aren't "gauges" of anything. They are set to "break" (not indicator types which aren't reliable anyway) at a set point. The setting is done against a torque master which should be calibrated, however. Torquing is a process, which requires controls, including knowing the wrench will "give" or indicate when that value is reached. That is dynamic torque. It depends on other factors to be accurate too. So we must be careful to NOT call wrenches "gauges" - the clue is in the name!

Re: Torque wrench question

When I was with an engine transmission manufacturing company, we use the clicker-wrench(rachet type can be used both ways) only at the start of shift on first drive of all assembly bolts/screws per station(assembly line). The (beam)needle type is there to check if the clicker type is indeed properly calibrated. Only QC uses the digital versions. All would not use or risk the digital/clicker type for loosening screws or bolts. The calibration/QC guys forbids it. We use the normal wrench for that. Although the (beam)needle type can be used to loosen screws/bolts we still do not use that for loosening. Torque wrenches are precision tools. They must not be subjected to abuse or misuse. Recalibration is required if the wrench is dropped. (In general, dial or click types are not as durable as beam memory torque wrenches.)

A beam wrench's "calibration" is based on the material's modulus of elasticity and physical geometry. It's essentially a cantilevered beam that's bending, and the pointer stays stationary. The modulus of elasticity of all steels are essentially the same at 30 x 10^6 PSI. The only way it could "go out of calibration" would be if you changed it's geometry (ground down the bar) or magically changed the material If you physically bend the pointer, yes, it's 0 spot is off, but the change in torque will be the same.

Walleye said:

I have various Torque wrenches, that are all calibrated in the clockwise manner only. they do work counter clockwise, our call outs are for tightening only.
Question was brought to my attention about lossening bolts counter clockwise messing up the calibration of my torque wrench. is this possible?
we have clicker type, digital, dial,etc.

Click to expand...

Are you really sure your Torque Wrench will not work counter clock wise? 'Generally', there is either a Dial button or an Arrow mark in the wrench. If it's a Dial button, you can use it on both directions by change of button. If it's an Arrow mark, you can remove the Head and fix it in the other side so that Arrow direction indicates your required direction of use.