(This post was last modified: 04-16-2020, 11:32 PM by DanLaw.)
Let's discuss alternatives:
For one, based on decades of experience with tool makers including Precision Instruments, "doubt" they would ship a torque wrench from the factory that had not been certified within limits and stickered with variance and date label on the wrench. Did you buy it new? Direct from PI or a certified dealer? Any reason to believe it a second or counterfeit? Presuming all these questions answered in a positive manner, you're golden there. While strongly prefer the other brands listed, PI is a quality tool.
RE the Taiwanese tool, not familiar with that brand so therefore it in doubt to some degree. Will suggest two methods to test: one halfassed, one the only proper way (under no conditions can performing the dual wrench coupling nut free hand possibly work for a plethora of reasons):
First a little theory:
on any but the highest end DOD electronic wrenches, the wrenches are only effectively accurate within the bounds of >20% of minimum setting and <80% of maximum setting. thus if one wants to test a known accurate wrench against an unknown accuracy wrench, one need match up the test settings to be cross checked within the meat of the ranges: e.g., presume there is a known certified wrench having a range of 20-120NM and a second unknown accuracy wrench having a range of 50-200NM, the effective range the torque wrenches could be accurately tested against each other without introducing range errors would be 80-100NM.
First (halfassed) method:
Using the known certified wrench, torque a clean known good fastener to the lowest end of the crossover range between the wrenches, then leaving that fastener in place to the previously torqued spec, test the second wrench SLOWLY using the same socket with a thin piece of brightly coloured electrical tape with a pencil thin sharpie line on it (aim small/miss small) noting carefully if the socket moves at all prior to the torque setting or indicates meeting the spec prior to barely moving. Repeat to the highest end of the crossover range. What does this provide - well that the second wrench may or may not be trust worthy over a very narrow range of its total effective range - so not much. Advisable at that point you proceed to test two.
Second (proper) method:
Start phoning Snap On dealers enquiring if they have a torque testing service and price out the cheapest one. Perhaps indicate you are not seeking any liability protection as just a private user (noncommercial) Barring that check with major tool distributors for a fixed operations torque tester - nearly every medium town with any industry of accumulation of garages has such a place, maybe your local airport FBO might know of one. Get creative. They will check throughout a range to arrive at a report that will be good for longer than the certification states provided you care for and store the wrench properly.
I absolutely stick by the characterization of the guy in the video having a desultory view of life. Not only does he not care about doing a critical job such as checking a precision instrument for accuracy properly but also demonstrates he doesn't care enough about the public good by creating a video advocating others adopt his errant ways. If you want to argue his diminished mental capacity due to disease, will stipulate that but still inadvisable.
Good question regarding dry vs lubed torque values. Manufacturers of end products rarely spec whether dry or wet torqued BUT there are standard tables of metals and fastener diametre/pitch tables that have this info. One easily accessed source are quality tool manufacturers such as CDI, FACom, SnapOn & Stahlwille among others another is the fastener engineering institute all available online.
Marko and
eeyore like this post