torque wrenches

Why do so many mechanics double click their torque wrench?Don`t they believe the first one or do they forget how many times they have clicked it?

 

It's to make sure, checking it twice dosnt hurt.

 

I do it to make sure that the bolt hasn't stretched and that the torque value has actually been reached...it's got nothing to do with being cool...I want to be able to sleep at night when the car I worked on just left for the other side of the country with a family in it...but then again; that's just me

 

Actually you're supposed to hold it a second or two after it clicks to make sure the fastener has set at the specified torque.

 

I also sleep better at night knowing I did a beautiful job ***embling a motor... Why even ask that question???

 

I dont use a clicker type wrench, they go out of adjustment too easy, beam type ones never do...

 

Well ****gy, I have a Snapon from the 50's thats a deadhead and it is still in spec, had it checked! Not bad for a 60 year old torq wrench!!!

 

I stick with my dial type snap on torqu-o-meters in foot and in lbs from the 1940's

 

Got to love the old stuff!!!

 

Been bit by the "click" torque wrenches...stick with the dial units IMO.

 

When I was certified to use a torque wrench at Boeing, they specifically said NOT to double-click it, that it could overtorque the fastener or tube fitting that I was installing.

I was walking through the paddock at the Pacific Northwest Historics one year when I watched a young mechanic torquing the lug nuts on one of the cars. Just as the thought entered my head, the crew chief barked at him, "Don't double-click your wrench".

Once is enough.

 

i do the bottom end, and right head on a top fuel funny car, and right head on a nostalgia fuel car. 1 click. Snap On click type.

The late model car top head studs go to 170 ft lbs. Rear main and mains to 130.

When you feel it comming in, the last stroke is 1 continuous stroke till it clicks. Stepping up to it is a no-no

When its tight, its tight.

good info here. ...

http://www.bmeltd.com/rod_maint.htm

 

I see a lot of uncle Bill's trying to cross over with there specs, the airplane specs are max torque and different that what we use on motorcycles and cars, the alum fasteners that Boeing uses are torqued dif than elsewhere, Just so there is no confusion, and I have Buddy's who work in different parts of Boeing, not just line workers.......

Same with the shipyards, just because a wire rope has a 1000# rating doesn't mean ya max it out, you use half of what it is rated at so it will last.

On the Harley Evo, you need to recheck when ya get to final torq, and the same for car alum heads, Flatheads more so than OHV's doesn't hurt so it is up to you, but it doesn't hurt.....

 

Good explanation

 

I go back over wheels. It will click if the wheel isn't seated against the hub. then you torque the other lugs and sometimes you end up with 2 or 3 loose lugnuts.I also do it with rocker ***emblies or anything that has a sequence.I work on cars for a living. I really don't want to hurt someone or destroy stuff. I don't double click per say but I do double check.

 

Not trusting those new-fangled clickey torque wrenches, I double checked with a beam type old school torque wrench. Just to make sure.

 

I like the clickers too,but didn't have one for many years,just the old dial job.But checking is good,yet i aften see too many adding a few extra lbs,and that is real bad to do,your better off a little under then over when it comes to torque.

 

I have old style click type now but I've been wanting to try the digital ones that also read "degrees after" that is required on some head bolts.

I recieved an E-mail from Eastwood yesterday and they have one on sale for a little over $100. I watched their online video demo and other than the number of ****on pushes to calibrate, it looks good. Probably made in China by political prisoners.

 

I've never heard of a beam type torque wrench, I've always used a click type. What do they look like?

 

Lone Star,

beam type are a beam with a scale near the handle.

 

Oh, ok I didn't know that's what they were called. Thanks

 

I can't elp but to add to this. Sure it is important to have a torque wrench as accurate as possible. Do not forget when using a torque wrench you are actually measuring friction. Friction can come from a few place a high spot on the land, a burr on the threads, debris on the threads. So keep in mind the coefficient of friction is calculated for the best possible conditions. For those of you who read Macchinery's Handbook you know that torque wrench fastener tensioning is accurate with-in +/-25%. Outside of ultra-sonic the most accurate method is by measuring elongation.

 

Dail type torque wrenchs are great for measuring rolling torque is small gear boxes.

 

Sorry One more comment. When it comes to click type wrenchs it is best to keep them a zero when in storage.

 

Thought I'd try posting here before starting a new thread..........Are there any decent economy priced (something from harbor freight or northern) torque wrenches that any of you guys would recommend buying.

I own mostly craftsman stuff (thought I'd never switch, dads toolbox, grandads tool box, etc are full of them) but the quality of there stuff is going down the tube.......Thank goodness for the lifetime warranty, I've went through several ratchets, (Now its a rebuild on ratchets instead of replacement). So I don't see putting out that kinda money on a craftsman torque wrench. I have a snap on 1/2" clicker and would like a 3/8". Just don't wanna shell out that kinda dough.

It's something I'm only gonna be using once in a while........

 

Double clicking probably is not a good idea. I think the old rule was to retorque (tighten/loosen) thru three cyles to allow the friction component to stabelize. ARP has a newer ***embly lube now that can achieve a preload accuracy of 95% with one torque cycle. This helped top fuel guys a bunch.

 

In the marine industry I retired from, double clicking was taught to be a no-no. This not only pertained to outboards but inboard (cast iron) type engines as well as diesels. Here is a read on the subject from a maker of torque reading equipment. Scroll down to the section on click types.

http://www.mountztorque.com/products/torque-wrenches

Don

 

When we are working on airplanes we are required to exercise the torque wrench a minimum of six times at the highest setting before we actually put the socket on a nut or bolt head and then you only click it once so you don't over torque something. There are torque values for a reason.

 

Same reason you put another bullet, a double-tap in the head of an 'adversary', to make sure its done right!!

Doc.

 

After a while of turning wrenches, especially the same nut or bolt, as the case may be, I.E ***embling engines, and torqing the same head bolts, one learns to distinguish between a R C H M or a B C H M.


HellRaiser