I have mentioned before that I work in a place that has very stringent calibration program, and I have access to a lot of torque wrenches.
But they actually rarely go out of calibration, and even the cheap ones seem to hold up pretty accurately.
So a lot of the question is simply how important is it to be accurate and how much are you willing to pay to be sure you are accurate.
As a practical matter, I do a lot of my home torquing with three tools: the Ritchey torque key, the Park TW-5 torque wrench, and a Craftsman 1/2" "Dr. Beam" torque wrench. But I have never had any of them recalibrated after purchase.
The same question comes up over the accuracy of pressure gages. So I have two "expensive" pressure gages and I also went out and bought about half a dozen of the cheapest gages I could find. But in direct comparison tests, all gages read the same pressure to within the ability of my eyes to read the gage.
So higher quality wrenches and gages probably hold up longer, and give greater piece of mind, but it would be arguable whether they actually give any more accurate results most of the time.
IRONY ALERT: STUMBLED ACROSS THIS TODAY:
Car Craft Tests Torque Wrenches: Guess Who Won!
February 8, 2013 By Dave
It’s not enough just to claim having the lowest prices around. A Scion is a lot cheaper than a Lexus, but, well… Now on the other hand, if you can claim lowest price AND the same quality (or better) than the high-priced brands, now we got ourselves a ball game.
In the April 2013 issue of Car Craft, in the Hands On section, I stumbled across an article entitled, “Testing Torque Wrenches”, by Jeff Smith. The gist of it was to compare the performance of 1/2-inch drive click torque wrenches from Craftsman ($240), Snap-on ($323) and the Pittsburgh model (#239 – $19.99) from Harbor Freight.
“Then we discovered a digital torque adapter sold by Harbor Freight (#68283). This small unit fits in between a standard 1/2-inch drive breaker bar and the socket, and using a digital strain gauge, it converts the torque applied through the adapter into a digital readout. At a typical Harbor Freight price of $39.99, we decided to include it in our test. We frankly didn’t expect this little unit to be very accurate. But the testing proved otherwise.”
After running the torque adapter through five consecutive applications of 70-lb.-ft. of torque, the average came out to be an “amazing 70.1 lb.-ft. In fact, when they tested it against a Snap-On digital torque wrench “costing far more,” the readings from the two tools were generally within 0.20 lb-ft.
As for the drive click torque wrench…
“… we also tested Harbor Freight’s 1/2-inch clicker torque wrench, and it was also very close. It also has a range of 20 to 150 lb-ft and a lifetime warranty. Accuracy after five consecutive tests at 70 lb-ft ranged from 68.8 lb-ft (-1.2) to 70.3 (+0.3), with an average error of 0.30 ft-lb over five tests. It doesn’t get much better than that for a mechanical torque wrench.”
Bottom line: You don’t have to pay an arm and a leg to get precision performance– and with your 20% Off Coupon, you can have the drive click torque wrench for just $16! For so much less than the competition, Harbor Freight’s 1/2-inch drive click torque wrench is the clear winner!http://blog.harborfreight.com/car-craft ... ue-wrench/
and more:http://www.carcraft.com/techarticles/cc ... h_testing/