Battery Operated Torque Indicator?

[OK-944]

It seems that on any number of engine rebuild instructional videos these days, that folks are often using a battery operated torque checking/setting device - attaches to a regular torque (or any) socket wrench, and lets out a "beep" when set torque is reached.

These devices usually claim to be quite accurate, and I would think that they'd also be cost effective as they are typically in the 50.00 to 100.00 range - probably less than having my set of three (Craftsman brand) torque wrenches re-calibrated.

My Craftsman's have been fine for most of the work I've done so far (including a past engine reseal), but now that I'm doing a full engine rebuild, I'd like to ensure the accuracy of my torque settings...and this particular battery operated device seems to be just the ticket. Any comments? Thanks!

[djnolan]

Bolt prep is every bit as important as the torque wrench. If the bolts are all prepped properly and turn in by hand, then they should all tighten the same even if the torque wrench is off a bit. You could do a home calibration by comparing several wrenches on something less critical such as a lugnut to see if there is a wide variation.

[maint]

I tried calibrating my cheap home torque wrench against a couple of good, calibrated ones from work by using a double nutted bolt held by sockets with torque wrench on each end. Listen for close to simultaneous clicks. Learned the difference between a cheap one and a good one. I could calibrate the cheap one to a torque setting no problem but as I change the setting it RAPIDLY goes out of calibration. The good ones "sort of" agreed with each other through the whole range.

[pfarah]

I learned a good torque wrench tip decades ago while in the NAVY working on torpedoes, missiles and bombs (great gig); whenever you change the torque setting always turn the dial/knob to it's lowest setting, then adjust to the new setting. If you overshoot the needed setting, don't just dial back to the value, reset the tool. When finished using the tool, always turn it all the way back (resting position). It's worked for me for almost 40yrs...

[TheSecondChris]

good tip, thanks.

[Jfrahm]

I always use a beam wrench for critical stuff as I feel the click wrenches may not maintain good enough calibration. If left for a long time cranked up to a high setting then they are probably not calibrated anymore.

The battery operated ones might be better, no idea. Strain gauge based bathroom scales seem to be pretty good over the long term, and the wrench can't be left with the spring wound up to 200 ft/lbs so they are probably pretty decent. I'll stick with a beam wrench for head and rod bolts though.