http://www.smartbolts.com/

The bolts have an indicator on the head to allow for visual inspection of proper torque... when it changes from red to black, it's torqued properly. Available in bolts ranging from 7/16" (M10) to 1 1/4" (M32), they measure elongation/tension of the bolt. Pretty slick...



There's also a high-resolution one that changes to multiple colors as you approach 100% design tension.

Anyone else think this idea would be great for lug nuts (assuming they're reusable)?

 

Hmm, pretty cool. One question though is if the torque indicated can be set to a specific torque number or if these are set to a particular torque from the factory.

 

Interesting idea. I don't know how you would use it for lug nuts though. A lug nut would not allow room for this indicator.



While I am not whole-heartedly disagreeing with this statement of theirs; do they mean to tell me that for the past 100? years torque wrenches have been ineffective?

 

Instead of running down the middle, it would run down the side.

 

Torque and bolt tension are different.

 

Most torque values are calculated to reach a certain bolt tension. Clean threads and a lubricant with the correct friction value are critical. Improper wrench technique is the cause of most errors though.

 

great idea!