flex head torque wrench worth the $?

I have a flex head Snap-on and I like it just fine. One good use is getting that little bit of extra clearance when doing wheel nuts, etc. They only flex a few degrees.

It depends how anal you are about torque measurement as to how you will accept the inaccuracy that a flex head *can* provide. For a fairly large capacity tool as these units are, I wouldn't care. On the other hand, I find no need for a flex head on a 1/2 inch unit anyway.

These two models are different designs, most likely from different manufacturers ("SK" doesn't make much of their own stuff - I think these torque wrenches are a good example - though SK may be a partner company to the true manufacturers). I have used the fixed head style in another brand and liked it. The flex head model looks like a higher quality unit similar in build to Snapon's standard click type line. It is rated and calibrated to +/-3% accuracy, which is very good. I would buy the cheaper one if I was just working at home on my own cars.

Toyota MDT in MO

I meant to qualify that statement by saying that when you flex the handle past perpendicular, other sideways stresses can build up in the gearhead and possibly throw the click point out of specs (more). Again, it's not enough for me to worry, but some people are anal and therein lies the reason for the post.

Toyota MDT in MO

If they are really anal they won't be using a spring-type torque wrench but instead a beam-type torque wrench. The spring types are slightly less accurate as they age. Of course this assumes that you calibrate your torque wrenches, either beam-type or spring-type, which I don't think that anybody does.

Ted

Some guys do get regular calibrations in the field. I assume that a larger percentage do in the manufacturing/machinery repair specialties. I have 4 wrenches in use (3 click), so each one gets very little wear. I can send all of them out for calibration every 3-5 years on a staggered schedule and I feel comfortable with that. I'm not anal about it, though. I would *probably* never cause an torque related error if forced to work without them, but it's better not to leave that to chance.

Toyota MDT in MO

I wouldnt pay the difference for it, because I have never needed this feature. Using an extension doesn't hurt anything...it doesn't make your readings less valid.

The point I was trying to make though is that accuracy is kind of a myth here. As you know springs are non-linear in their resistance in that towards the end of compression resistance goes way up, and towards the beginning of it resistance goes way down. Thus a torque wrench with a scale of, say 0-150 foot pounds is going to be most accurate in the 20-120 foot pound range.

Also, the other thing is percentage of error. If a torque wrench reads consistantly low by 10 foot pounds, it probably doesen't matter if all your using it for is tightening lug nuts to 100 foot pounds, since that only represents a 10% measurement error. While if your using it for torquing stuff to 25 foot pounds that represents almost a 50% measurement error, very serious.

So the truly anal are going to be frantically pulling out their hair here because as it is easy to see, your never going to be assured that the torque you put on a specific fastner is -exactly- what you think it is. ;-)

Ted

Well, I would hope that the OP plans to use the 0 - 150 ft/lb torque wrench within reason. For example, cam cap bolts are right out, while wheel nuts and most headbolts are perfectly suited tasks.

Toyota MDT in MO

Get a torque wrench that doesn't use springs.

True. Ya get what you pay for.

Again, it depends on what you bought and what range it is intended to work at.