Location: 1.Just because I'm paranoid doesn't mean people aren't out to get me... 2.That which does not kill me will probably hurt like hell...3.Spare me the Lima Beans.
Torque wrench questions.
Trying to find out if this is true or just a myth. Years ago, when I started "wrenching" I was told that when using a torque wrench to avoid using any extensions as they alter the torque reading of the wrench.
Since then I've always tried to avoid using any extensions when torqueing any bolts. Is the above statement true?
You mean extensions on the sockets?? that's baloney...I have NO idea where that came from.....
probably from using them with an impact, that will add enough spring under those conditions to allow too much dissipation of the impact hammer blows from reaching the bolt....
They may have meant to not use a "cheater bar" with a torque wrench. If you place your hand anywhere other than the center of the handle you will alter the torque value that is produced by the torque wrench.
Location: 1.Just because I'm paranoid doesn't mean people aren't out to get me... 2.That which does not kill me will probably hurt like hell...3.Spare me the Lima Beans.
Re: Torque wrench questions. (mrvette)
No, not an impact wrench...but a hand torque wrench. As in when torqueing head bolts intakes and such.
Well that's what I"m saying, a hand torque wrench is not affected by any socket extensions....you do need to use the handle of the wrench in decent position though...,
I think the tale you are hearing sprang from the impact situation described above....
Technically an extension does "twist" so the torque needed to twist it would affect the reading. The amount of error is dependant on the size of the extension.. A big 1/2" drive would be better than a 1/4" drive. Im sure there is a formula that is more complex. Also if you use a "crows foot", you must use it 90 deg. from the torque wrench handle which will not effect the reading. In line WILL increase the torque by the length of the crows foot. (proportionally). Cheater bars will not affect torque reading.
I see there is a lot of confusion here.... so let me elaborate. I you use a socket extension, there is a point at which the extension will twist... If the torque of the bolt you are installing is more the the twist point of the paticular extension the the above is true. However... this is not likely to happen. It's only in the extremes that this would happen.
Blue, of course you right there, but like you I"m thinking of the typical say Sears clicker 1/2 drive torque wrench, and say a 6 inch extension that's about 5/8 diameter on the shank, and then the socket....some semblance of common sense....not say adapting down the 3/8 extension and torqueing main cap bolts to 95 ft lbs....that's about screwey....and not much NEED to be that way, except tool shortage....
Location: I may be getting old but I refuse to grow up
Re: Torque wrench questions. (bluevetteman)
Quote:
Technically an extension does "twist" so the torque needed to twist it would affect the reading. The amount of error is dependant on the size of the extension.. A big 1/2" drive would be better than a 1/4" drive. Im sure there is a formula that is more complex. Also if you use a "crows foot", you must use it 90 deg. from the torque wrench handle which will not effect the reading. In line WILL increase the torque by the length of the crows foot. (proportionally). Cheater bars will not affect torque reading.
I see there is a lot of confusion here.... so let me elaborate. I you use a socket extension, there is a point at which the extension will twist... If the torque of the bolt you are installing is more the the twist point of the paticular extension the the above is true. However... this is not likely to happen. It's only in the extremes that this would happen.
:iagree:
I watched the guys at this tire place I buy tires from use a Torque limiting extension so that the wheel nuts don't get more than 80 ft/lbs. I try to avoud the use of extetions whenever possible and when I have to I use the shortest one possible.
Corvette Store
Torque wrench questions.
