Rick
August 19, 2015, 4:14pm
18
48Willys:
This is true up to a point. I also have many torque wrenches. However, as an aircraft mechanic, all of my torque wrenches are required to be certified to be accurate throughout their entire range.
The FAA does not allow me to use a non-certified torque wrench. When I bought my brand new Snap-On torque wrench I could not use it on aircraft until it had been tested & certified to be accurate throughout its entire range. It was brand new & was not able to meet these specifications. My Snap-On dealer & I went through six wrenches before we found one that would pass the FAA specs. He sold the other ones to auto mechanics. Try not to think about that.
All of my wrenches must be certified at least once a year. Since the certification process takes from two days to two weeks, & I use mine at least three times a day, I have two sets of wrenches & send them in six months apart.
All of my torque wrenches are either Mac, or Snap-On. Most other brands will not pass the FAA required certification year after year. I had one Craftsman large (300ft-lb) torque wrench pass certs for 12 years before it failed the certs. Not bad.
For home use, most brand name torque wrenches are fine. The ones that do not have a known good brand are very suspect as to their accuracy. If it says “made in China”, it is most likely scrap metal.
As has been said, torque is torque. As long as the torque wrench & the driven fastener are aligned concentrically, the wrench is accurate. If you need to use a crows foot or an offset attachment with your torque wrench, some math will need to be done.
Lastly, store your torque wrench with the adjustment at the bottom setting. It will stay accurate longer.
IHTH, 48.
Grab you Snap-on catalog and read the fine print on the torque wrench page carefully. While they advertise 1% accuracy, that is only for 20%-100%. There will be a disclaimer that says at <20% the accuracy is worse, usually + - 20%