Torque stick not working how i'd imagine

[garlicbreadman]

Setup:
1/2" drive 65ft pd torque stick
1/2" drive dewalt cordless 20v impact driver (only 1 setting)

I am tightening one of my lug nuts and i can see the stick continuing to torque my nuts beyond 65ft pd. I verified this with my torque wrench and sure enough at 80ft, the torque wrench clicked with no movement. I loosened the lug nut with a breaker bar and can estimate it was tightened to probably close to 90-100ft pds. I thought these were suppose to stop at what it's rated for, in this case, 65ft pds.

I bought this torque stick so i can get an even torque while the car is in the air before i do a final torque on the ground.

Your thoughts?

 

[Ethan1]

It takes more torque to get the lug nut moving again than it does when it already moving. This is called static friction and sliding friction.

Originally Posted By: garlicbreadman
I bought this torque stick so i can get an even torque while the car is in the air before i do a final torque on the ground.


That's pretty, um, hardcore.

 

[Falken]

I read somewhere a long time ago that air tools perform better with torque sticks than an electric impact. Electrics don't have the "pulse" of energy the torque stick needs to work properly.

The best way is to gently zip the nuts on then finish with a click style torque wrench.

 

[Vikas]

I have not really understood the physics of the torque stick. I know that they do cut down on the final torque because of the springy nature of the stick but there is nothing which will give it a single torque value at the output when input torque value is varied greatly.

I can see that if stick were to be calibrated to start twisting at 65 ftlb but if you keep on applying 300 ft-lb at the other end, it will start transferring that 300 ft-lb to the wheel.

Are you stopping the gun instantly when it clicks? I suspect that is the only way torque sticks are designed to function.

 

[JW_Ford]

I always used torque sticks but I turned my impact down to the lowest setting. They were always a little over torqued but its more important that the wheel has even pressure and enough of it. I have seen wheels fall off from people that torque them by hand as well as torque sticks I dont think you need to be doing both IMO.

 

[SIXSPEED]

Originally Posted By: JW_Ford
I always used torque sticks but I turned my impact down to the lowest setting. They were always a little over torqued but its more important that the wheel has even pressure and enough of it. I have seen wheels fall off from people that torque them by hand as well as torque sticks I dont think you need to be doing both IMO.

You should always re-torque lug nuts with a torque wrench after driving around for a few miles.

 

[ajchien]

I thought most torque sticks are calibrated for air impacts with a specific impact rating and specific air pressure. If your electric impact is more powerful than the specs, your final torque will be higher. If you impact is weaker, it'll under torque.

I know you've already bought the stick. Now what? Well, I also use a 80 ft lb torque stick with an electric impact. Do some trial and error, for me, first time around when the impact starts hitting, I let it hammer 4-5 times. Second time around, another 4-8 hits and I'm roughly on target with my goal of 80 ft lbs. I know if I keep hammering at it for 30 seconds, I'll be way over torqued. I know if I just go once around and barely let it hammer, I'm inconsistently under torqued.

As good and consistent as a torque wrench? I don't think so. Are my wheels falling off? No. Are they far over Tightened? No. Good enough for you? Not my decision.

 

[ajchien]

Found one example link:

http://www.procutinternational.com/pdf/old_pdf/Torqstik_Chart.pdf

The above brand calibrated their torque sticks for an impact rated at 250 ft lbs. I'm sure there are variations depending on brand.

 

[JW_Ford]

You should always re-torque lug nuts with a torque wrench after driving around for a few miles.[/quote]

I think Ford says after 100 miles but what customer would ever come back in for that ha.

 

[Falken]

When I lived in CowTown re-torquing was CalTire policy.

Clicking around your car with your own torque wrench after a week or two is a great idea in my books.

 

[SIXSPEED]

Originally Posted By: Falken
When I lived in CowTown re-torquing was CalTire policy.

Clicking around your car with your own torque wrench after a week or two is a great idea in my books.

Personal experience ... sometimes the tire shop will fail to tighten one (or more) lug nuts.

 

[RedVic]

I have never seen a wheel fall off because it was hand torqued with a torque wrench.

I always hand torque with a torque wrench and in all my years I have never had a wheel come loose.

 

[Trav]

Originally Posted By: ajchien
Found one example link:

http://www.procutinternational.com/pdf/old_pdf/Torqstik_Chart.pdf

The above brand calibrated their torque sticks for an impact rated at 250 ft lbs. I'm sure there are variations depending on brand.


Interesting info in that.

Quote:

TorqStik is designed to work only with pneumatic impact wrenches with output of 250 ft*lbs.
Do not use a TorqStik until you have checked to determine that the impact gun has the output listed above.
Do not touch torqStik while impact gun is running! Never hold the shaft or socket of the TorqStik when driving it with the impact gun; serious injury may result!
Failure to use impact wrenches outputting the torque specified above may result in: fracture of the TorqStik, possibility of flying metal fragments, and/or: nut torque above
or below rated values resulting in either wheel damage or wheels falling off