Torque Wrench Question

[Deano_1]

Hey Guys,

Mounted all four new tires and rims on without a problem, but I do have a question. When i went to put tighten the lugs with the torque wrench, I needed to add an extension onto the torque wrench, otherwise I couldn't get the wrench on the lugs. My question is, with the added length, (about 12 inches with the deep socket and extension), how much does this change the the actual reading? So by adding a foot is my reading actually less than the 100# of torque on the wrench. By the way, Sears had a 1/2 drive wrench for $39.

Thanks,

Deano

[Durb]

rbpru wrote:
I do not know what the tire shop set the torque of their air guns at but it was more than the 150 lbs I set my wrench too.

I torque to 90 lbs and check when get to my desination. I have never had it change after the third check.

If the pre torque (air gun) is more than the desired torque then the torque wrench is just a placebo and might as well stay in the case. The torque wrench needs to turn the lug nut in order to be effective. If over torqued, loosen one lug nut and re torque. Move to the next lug nut in the pattern and do the same. This technique will eliminate any cross talk between the lug nuts. Use good technique when loading the torque wrench and the nuts will be right on.

[gmw_photos]

joshuajim wrote:
The only comment I would have on the 3 step torquing is to be careful not to get the second torque value too close to the third. It takes considerably more torque to "break" the fastener loose than it does to keep it turning. I.E if your second torque was 70 and your goal was 90, it might take more than 90 to break the fastener loose from static torque to sliding torque.

Fair enough. The dexter manual calls for three stages of 20-25, 50-60, 90-120 ft-lbs for 14, 15 and 16 inch steels wheels.

[rbpru]

I do not know what the tire shop set the torque of their air guns at but it was more than the 150 lbs I set my wrench too.

I torque to 90 lbs and check when get to my desination. I have never had it change after the third check.

[joshuajim]

The only comment I would have on the 3 step torquing is to be careful not to get the second torque value too close to the third. It takes considerably more torque to "break" the fastener loose than it does to keep it turning. I.E if your second torque was 70 and your goal was 90, it might take more than 90 to break the fastener loose from static torque to sliding torque.

[dannytas]

bguy wrote:
The difference it makes makes no difference.

A Man of few words and a lot of substance...well said

[bguy]

The difference it makes makes no difference.

[rbpru]

I have a Harbor Freight torque wrench and I use a six inch extension.

If the extension comes straight off the nut it makes no difference how long it is.

It is just transferring the torque from the wrench to the nut.

[LarryJM]

ol' yeller wrote:
A little known tip about storing a clicker type torque wrench is to be sure to release the tension to zero when putting the tool away.

Most decent torque wrenches have a "STOP" index where you are supposed to leave the wrench at for storage which does effectively what you are saying ... maybe not zero, but enough for proper long term storage.

Larry

[ol__yeller]

A little known tip about storing a clicker type torque wrench is to be sure to release the tension to zero when putting the tool away.

[moresmoke]

smkettner wrote:
Extension has ZERO effect on torque with a hand wrench.
Impact gun will be different.

Correct, As long as you are not "bouncing" on the wrench, the extension will have zero effect. Push-click-hold, the extension does wind up, but the torque on both ends of the extension is the same. If the torque was different on either end of the extension, something would be moving.

Its not usually a problem on 100 ftlbs, but I have seen guys trying to torque 6-700 ftlb by hand and they like to put a jumping motion into pulling on the wrench. This will create erratic readings.

[time2roll]

Extension has ZERO effect on torque with a hand wrench.
Impact gun will be different.

[Durb]

I was doing torque training for a large military contractor. Their rule was to add 10% to the torque setting for every 2" of extension length. I questioned this so we put a wrench and a 10" extension on a transducer and digital meter and measured the results. Not even close. At a 100 ft-lbs and a stout 5" extension the wind up will be negligible. It is possible to use long spindly extensions at high settings and the torsion wind up is enough to keep the wrench from clicking. This is the theory behind torque sticks.

[Hannibal]

I carry a torque wrench with a 12" extension and 13/16" socket to check them every now and then. Like you, I need the extension to reach the lug nuts. Works like a champ.

[Deano_1]

Thanks, for the responses. I didn't make the wrench any longer. I only used the extension with a deep socket, otherwise the wrench would keep hitting the the tire if that makes sense.


I did as suggested and used the the three-step process and finished with a setting of 105 lbs. Good to know will only make a negligible difference in the readings.

Deano