I have seen too many experienced "mechanics", my Dad called them "hammer mechanics" and this includes factory trained "stealarship mechanics" that can only use an impact wrench when a torque wrench is called for.
"tighten until it strips or snaps, then back off half a turn". then they're real easy to get off next time.
The guys who get to me are the tire shop guys who rock on your lug nuts with a big impact. Then there I sit along side the highway, with a flat, in the rain, in the dark, trying to loosen them with an OEM lug wrench... Had this experience on a couple of occasions before I found the "right" tire shop. My current guys use a torque wrench.
My buddy Ed works in the shop on all our projects with my brother and I. He tightens stuff up like it was going up with the space shuttle or something. He has wrung off more bolt heads, stripped more threads, over tightened more fasteners and broken more ratchets over the years than I can count. Whenever we run into something that won't come loose we say it's been "Ed'ed On". It doesn't matter how many times you tell him about it he just keeps on doin it. Sometimes he's the only one that can get the shit loose.
I've got a friend who I won't let near anything of mine with a wrench or socket. He has absolutely no idea how tight he's making things, and he's got these big popeye arms to boot. He breaks everything he tightens. a great guy to have around if you need something broken loose. Ken
My brother who is a good machinist comes over to my shop to use the Bridgeport. After he left, I go to set up a job and the freakin' draw bar is as tight as a clam's ass. Way over tightened! I had to tell him to go easier on it. Bob
The shop that fixes my OT cars, they use those torque sticks on the lugs. Even then they're pretty tight. Everyone in my family carries a length of black pipe that fits over their lug wrenches just in case. Bob
I had tires put on my daily driver a couple of years ago and when I picked up the car I noticed the mechanics putting on other customers cars with an impact wrench. Last year I got a flat and my car has a theft proof lock on each wheel. The mechanic must have had his impact wrench set with about 200 psi because he rounded the lug. It took me an hour to drill it out!
it's folks like those that keep mechanics and parts guys fed. keep 'em coming; I like my dinner. first thing a lot of guys need to ditch is a beam torque wrench. they're as inaccurate as hell and a lot of people abuse them using them as breaker bars, making them even MORE inaccurate. Motor Manuals, Chiltons (the old ones, anyway), Haynes, all list torque settings. once you get the sense of what a certain value is with the TW, you can come close with the 3/8ths, sometimes on the money but it's insurance to check anyway. I apprenticed with a guy building British cars, he used to go behind me and loosen bolts so i'd learn to double check them. we used a lot of antisieze and pipe dope too.
The Jalopy Journal
