Recommendations for inch pound torque wrenches Options

[fiacra]

Several recent threads about oil screens has me thinking I need to invest in another tool - a torque wrench that is more accurate at the lower end of scale. To that end, seeking recommendations for which inch pound torque wrench to buy. What do you have and would you recommend it? I suspect there will be lots of different opinions, but lets hear them!

[chmillman]

This thread was very interesting, it caused me to check out a bunch of videos and info on torque/torque wrenches.

First of all on the specified torque values themselves – do we know what percent of yield-strength safety factor is assumed by the values given in the 914 manual? 75%? 90%? One could assume that the values given are either a max number not to exceed, or a middle number with a bit of margin on either side… as dead accuracy on the part of the user or the tool can never be assumed. As an aside, the factory manual for my ’57 T-Bird gives torque values for everything as a range, not a fixed number. I always try to hit the middle of that range.

I assume the Porsche/VW engineers specified the torque values with a decent safety margin*, but again, I don’t know if those are the limits which should absolutely not be exceeded, or a target number with some margin on either side. If it’s the first one, then given the possible inaccuracy of the torque wrench and other conditions, torquing right to spec could be dangerous…

*excepting of course known engineering “oversights”, like the oil strainer stud…

And of course, the condition of the assembly to which the torque is applied also can vary. Threads completely dry or traces of oil, what kind of washer, etc. Even more arguments for a decent safety margin.

As far as the wrenches themselves, like many others, I have several “clicker” torque wrenches covering the range from 4nm (3 ft-lbs) to 200nm (150 ft-lbs). After watching a bunch of videos, it seems that these may actually be the least accurate. The old-fashioned “bar” style wrenches (if properly calibrated) have been known to actually beat clickers for accuracy. But most surprisingly it seems that even a relatively inexpensive digital torque wrench (load-cell technology) these days can be as accurate or more than an expensive clicker wrench which is based on spring tension. I think the digital ones could be especially good when working in the low torque ranges where it’s hard to feel the “click”.

Anyway, personally I haven’t yet had a failure from under or over torquing something, but it’s always good to be aware of the issues involved and what those numbers mean.

https://www.youtube.com/watch?v=lVswvpyvBxw
https://www.youtube.com/watch?v=fa4VFiNa0Xs&t=895s
https://www.youtube.com/watch?v=je9_m-77k_U&t=825s