Question on using a torque wrench

[Mahlstedtd]

Hi all, New design torque wrenches will display torque settings. They can tell you how much over you went. They can remember your settings for different torque. They vibrate and have warning lights to let you know when you are close to the actual setting. Best of all they only cost $650.00.

[aircommuter]

Not only that but some can keep track of degrees of rotation and show it digitally. Really a nice feature.
Like this one.

[Springerdad]

Originally Posted by TitanMike

Nothing wrong with using an impact wrench on the lugs. It just has to be used properly. They actually make torque limiting impact wrenches today that are great for tire shop work.

And "Torque Sticks" They are very accurate...….. I've checked them.

[TitanMike]

Originally Posted by Springerdad

And "Torque Sticks" They are very accurate...….. I've checked them.

My only issue with torque sticks is that their final torque reading can vary from impact wrench to impact wrench. It depends on the actual "clutch" or "hammer unit the wrench uses.

Now if one is using one wrench all the time and has checked it's accuracy, no worries.

[Philkaty]

When using a torque wrench, the nut needs to move or it is over torqued. I worked on aircraft in the navy and work for an aerospace company now. We have to be certified for torque tools.

[aircommuter]

I think the nut must be moving to get accurate torque after that checking torque can only tell you if is at correct torque or over, unless one wants to set the wrench slightly up each time until the friction can be overcome. Now you know it is over for sure and maybe it was correct before you started.

Many automotive applications now use a minimum torque then a specified number of degrees for the final. This provides a more accurate and uniform clamping force which is often the goal. This method relies on the thread pitch which is a constant regardless of friction. This method has been used on European cars for many years.

[Iwannacamp]

Originally Posted by NJKris

Navy was still using Beam style torque wrenches in the 80's. I don't remember them having ratcheting style heads.

lol

[GoneSouth10]

I'm not sure what's worse - all you "Torque-Nuts" (yes, pun intended) throwing up 27 posts about torque wrenches, torque sticks, lug nuts and breaker bars . . . or me reading through all 27!!!
I guess this is what happens when we're forced to stay at home!!

[TitanMike]

Originally Posted by GoneSouth10

I'm not sure what's worse - all you "Torque-Nuts" (yes, pun intended) throwing up 27 posts about torque wrenches, torque sticks, lug nuts and breaker bars . . . or me reading through all 27!!!
I guess this is what happens when we're forced to stay at home!!

Maybe that's why posts tend to drop off when the weather is nice and everyone is out camping, especially beyond internet coverage

[babock]

Originally Posted by GoneSouth10

I guess this is what happens when we're forced to stay at home!!

Hopefully you don't stay at home! We have been camping all year.

[Larry0071]

FAA Certification A/P here.

When I went to school in the early 90's at PIA, we learned that you can not "check torque" on a torqued fastener by setting the tool to the desired torque. The reason was called something like "break-away torque" if I recall correctly.

The premise is that if you torque a fastener to say 100 lb/ft, and then set the torque wrench to 105 lb/ft and "check" the torque... you would not get motion on the fastener and the wrench would indicate 105 because the break-away torque is higher than the constant motion torque. Because of this, we were taught that to properly TQ any critical fastener you would back the fastener off and smoothly pull that fastener to torque.

The other thing is some fasteners are torque rated dry, and some are rated with a specified lubricant. This dramatically effects clamping loads at a given torque setting. If you are applying anti-seize or oil to the studs, your actually applying more load on the fastener at your torque setting than you suspect. For something as mundane as automotive wheel studs this is not a big deal, but I'm just throwing it out there as another fact to be aware of.

[youroo]

Originally Posted by Larry0071

FAA Certification A/P here.

When I went to school in the early 90's at PIA, we learned that you can not "check torque" on a torqued fastener by setting the tool to the desired torque. The reason was called something like "break-away torque" if I recall correctly.

The premise is that if you torque a fastener to say 100 lb/ft, and then set the torque wrench to 105 lb/ft and "check" the torque... you would not get motion on the fastener and the wrench would indicate 105 because the break-away torque is higher than the constant motion torque. Because of this, we were taught that to properly TQ any critical fastener you would back the fastener off and smoothly pull that fastener to torque.

The other thing is some fasteners are torque rated dry, and some are rated with a specified lubricant. This dramatically effects clamping loads at a given torque setting. If you are applying anti-seize or oil to the studs, your actually applying more load on the fastener at your torque setting than you suspect. For something as mundane as automotive wheel studs this is not a big deal, but I'm just throwing it out there as another fact to be aware of.

"Mundane" apparently you have not heard the Song "You found a fine time to leave me Loose Wheel"! Youroo!!

[TitanMike]

Originally Posted by Larry0071

For something as mundane as automotive wheel studs this is not a big deal, but I'm just throwing it out there as another fact to be aware of.

Especially when one looks at a chart showing the range of torque specs on any given vehicle. Some torque specs can have huge ranges, sometimes as much as 25 ft lbs on smaller studs up to 50 or more ft/lbs on larger diameter studs.

Definitely not as critical as in the aerospace industry or for engine assembly.

[Philkaty]

Originally Posted by Iwannacamp

lol

yeah they got smart some how... I retired in 05 and we had them

[Nastynotchback1]

Never use a torque wrench to loosen anything. You will ruin it.

[aircommuter]

Originally Posted by Nastynotchback1

Never use a torque wrench to loosen anything. You will ruin it.

i think that has been brought up before. Some torque wrenches may be damaged but most are capable of torquing left handed nuts and bolts. I know all of mine are. But there is no real reason for using it to loosen bolts/nuts.

[Nastynotchback1]

Originally Posted by aircommuter

i think that has been brought up before. Some torque wrenches may be damaged but most are capable of torquing left handed nuts and bolts. I know all of mine are. But there is no real reason for using it to loosen bolts/nuts.

Right tool for the right job. A left hand thread can be torqued because your just torquing the bolt. Your not breaking it loose. I'm not gonna take my 750.00 Snap-on to break bolts loose. It cost around 75.00 to have them calibrated. I will use my cheaper breaker bar.

[herkyfe]

Once a wheel has been torqued, the retorque is to check that the lug nut hasn't loosened (backed off). If there's a lug nut that has backed off you need to do a follow up retorque. Now that all being said, if you back off the lug nuts to retorque, you just undid what you were doing. Just checkthat the lugnuts are still at the torque valueand if not, retorque after the specified mileage recommended. If you back off this process will never stop. I rambled on but hope you got the drift about proper retorqueing.

[jeffnick]

We re-torque trailer lug nuts because they become loose. Put the torque wrench on the nut and torque to the specified ft-lbs. If the lug nut doesn't move it's fine. If it does move, put it at the proper torque and check it again after a few miles, and do it again after a few more miles until the reading is stationary. It's not so much how accurate your trailer lug nut ft-lbs are, more that they are consistent.

At least that's how I've come to do it after losing a newly installed trailer tire/wheel...at 55 mph, as a teen ager.


And here's some confirmation.
https://72land-n-sea.blogspot.com/20...ea-rescue.html
I personally torqued the new wheels to 110# and double checked them all before we hit the road. After about 50 miles I checked them again - several were loose. At 100 more miles I still found a couple that needed a little more oomph. The next 100 miles they were all snug.

[Honest Abe]

Hey! Was that On-Sale Sears torque wrench an ASE or Metric unit?
Don't get your Foot-Pounds mixed up with your Newton-Metre's.