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Sun Nov 29, 2009 5:13 pm

I don't have a torque wrench and am loath to buy one. I believe it's possible to measure the moment of force with a normal wrench with a certain pound force perpendicular at one foot from the end of the wrench. In practice, does anyone use this?

Sun Nov 29, 2009 5:25 pm

tomfreo wrote: In practice, does anyone use this?

I've done it in an emergency, but even a cheapo $30 torque wrench is hundreds less than anything I might screw up by guessing. Your theory is sound, how do you propose to measure this force?

And why do you have this phobia towards investing in a few basic tools?

Sun Nov 29, 2009 5:29 pm

They don't consider torque specs "critical measurements" for nothin. Even a cheapo beam type torque wrench is better than a guess.

Sun Nov 29, 2009 5:55 pm

Well I was thinking you could get some kind of weight scale attached a foot from the wrench 'head' and pull on it until you get the desired torque. Don't know how practical it would be in practice, was kind of curious whether anyone actually does this.

Sun Nov 29, 2009 6:27 pm

there is a way - too loose and things fall off, too tight and it breaks.

I cannot in my wildest dreams imagine anyone trying to work on a car without some basic tools. Get a used beam one from CL or the swap meet for under $10.

A fastner is designed to work within a set range of stretch. Too loose or too tight and they fail.

Sun Nov 29, 2009 6:35 pm

I just don't understand why the OP would want to complicate a simple procedure with a correct tool. Sorry tomfreo I don't get it.

Sun Nov 29, 2009 6:42 pm

Quote: Well I was thinking you could get some kind of weight scale attached a foot from the wrench 'head' and pull on it until you get the desired torque. Don't know how practical it would be in practice, was kind of curious whether anyone actually does this.

be sure to take a video as you get whaped upside the head with this contraption. Why not reinvent the wheel while you are at it. I hope to G_D that you are not a relative of mine somehow because if so I have failed you as an uncle or cousin. Get a torque wrench. I still have the ones I bought 30 to 40 years ago. They can be recalibrated. The beam ones never require calibration.

Sun Nov 29, 2009 6:50 pm

tomfreo wrote: I ... am loath to buy one.

Why? If it's too much money how about going to a flea market? I got lots of my tools from a big flea market near me. Or borrow one from a friend? You don't need it for every job, just a few critical ones.

Sun Nov 29, 2009 6:56 pm

VDubTech wrote: They don't consider torque specs "critical measurements" for nothin. Even a cheapo beam type torque wrench is better than a guess.

and, a cheapo beam style torque wrench is almost always more accurate than the click style if read carefully. other than being wicked expensive, the click style needs calibrations from time to time. some disagree that click style wrenches are inaccurate. but hey, if that's true i wonder why every auto machinist i have ever dealt with wont use anything but the cheaper beam style. and yes i have asked them why- just guess what they tell me...

please- for the love of god- just go to ebay, search "craftsman torque wrench" and lay down the 10 bucks. do you really want to lose your oil, or else wreck the case threads by overtightening? for instance?

Sun Nov 29, 2009 6:58 pm

stand on a bathroom scale. If your wrench is a foot long, use unought forch to lower your body weight by the force you wish to put on the part.
If you weight 200 lbs and want 50 pounds of torque push until the scale reads 150. This is for a 12 inch wrench only. If the wrench is 2 feet long, puch until weight goes down by 25.

Edited for spelling per instructions of picky chat room friends.... :D

Sun Nov 29, 2009 7:30 pm

an accurate bathroom scale costs more than a torque wrench
Aloha
tp

Sun Nov 29, 2009 7:30 pm

Quote: every auto machinist i have ever dealt with wont use anything but the cheaper beam style

The grease in the clickers hardens and then one day they go from 45 ft lbs to 300 ft lbs and they break something important that pisses off one of their clients. Owners of machine shops get tired of replacing them. Beam wrenchs only require that the beam is centered on -0- to calibrate them as the laws of physics are the same as they were when the wrench was made.

Team Torque is where I send my cliickers and when they are done they send back a chart of what it says vs what it actually is. Their equipment can be traced back to the Nat'l standards. I put the numbers on a small Excel spreadsheet, cut it out and tape it to the beam - about a 1.5" square piece of paper. Extememly accurate if you send them off every few years.

Sun Nov 29, 2009 8:15 pm

ive been a professional mechanic all my life, and i usually only ever use a torque wrench on the engine [heads, bearing caps, ect.] , anything else you can get a feel for.

Sun Nov 29, 2009 9:28 pm

I own four torque wrenches, 1/4-1/2 inch beams plus a 1/2 click, so I have what I need when I need it. Like mikenwheeler I only regularly use a torque wrench for a few things, mostly engine overhaul stuff like he mentions. I also almost always use them to torque my lug nuts, especially on aluminium/magnesium style wheels.

On some applications like the rear wheel hub nuts I just stand a certain distance out on my breaker bar like you suggest doing. The exact torque here is not all that important as you will probably need to tighten the nut some more to get the slots in the nut to line up with the hole in the axle.

If you don't wish to afford a torque wrench though, I suggest you also do without a socket set and other wrenches. A hammer and chisel is all you need to loosen and tighten most fasteners. 8)

Sun Nov 29, 2009 9:34 pm

tomfreo wrote: I don't have a torque wrench and am loath to buy one. I believe it's possible to measure the moment of force with a normal wrench with a certain pound force perpendicular at one foot from the end of the wrench. In practice, does anyone use this?

I am a machinst and have been in the trade for almost forty years, I can feel the difference in diameter of two gage pins that are only .0002 by just holding them in my hand but why would I when I have all these great measuring tools, that sensative feel has little practical value. I am sure with enough practice you could duplicate some torque specs but why take the chance, you could easily exceed the cost of a decent torque wrench in buying special drill, taps and extractors to remove broken studs from over torque.

That is great in theory but not really practical if you do much mechanical work especially engine work and what do you do for inch pounds.

Here are some of my torque wrenches and I use them all the time even for carbs.

Phil

Sun Nov 29, 2009 10:24 pm

I put a cheapo Harbor Freight clicker torque wrench in each of the family's vehicles, with the proper factory-specified lug nut torque for that vehicle's wheels, painted on the wrench's plastic case. It's a cheap way to avoid warped rotors, whether I put on the spare or AAA comes out to do it. Odd thing was, none of those wrenches was more than 2-3 lb/ft off the reading of my just-rebuilt & re-calibrated Snap-On! (even though they're just for lug nuts, it's good to know they're not horribly inaccurate, just in case of a different type of on-the-road emergency!)

BTW clicker-style torque wrenches are most accurate in the upper half of their indicated range. Not very reassuring when trying to torque something to 12 lb/ft with a 250 lb/ft clicker. The beam-type OTOH requires that you be able to see the dial calibrations, not always possible. Seems like the OP's system would really present some issues.

So, yeah, if you do a lot of work on a wide range of vehicles & equipment, you may end up with a tool box drawer or two taken up by just quality torque wrenches of varying types & sizes. IMO it's one of those CYA things.

Sun Nov 29, 2009 10:34 pm

Quote: It's a cheap way to avoid warped rotors

X2
and out of round rims. When cone nuts are over tightened they deform the steel into the center hub area. That causes the wheel to no longer center exactly on the center hub area so you will never get it balanced right as most balancers use the center hub area. It will be balanced on the deformed center hub and off then when mounted on the wheel studs.

Mon Nov 30, 2009 12:14 am

I use both 3/8" and a 1/2" drive beam style torque wrenches. Once bought a Harbor Freight michrometer adjusting type torque wrench and it was extremely inaccurate. So returned and exchanged it. The replacement was even worse. Major errors in all ranges of the adjustment. So I trashed it!
At the same time it is no big deal to get accurate torques without a torque wrench in an emergency by properly applying physics and math. If you question whether or not you can do it, then don't do it. As you probably won't be able to.

This is also somewhat funny since so many bus folks could care less by not even having a manual to know what torques should be applied.

Mon Nov 30, 2009 12:24 am

i scored a unused snapon 3/8 for 100 bucks. im not into high dollar tools, but when it comes to torque specs, especially on the head job i just did on my Thing, i don't mess around

Mon Nov 30, 2009 12:38 am

I use torque wrench's almost every day and some people think beam style are low budget or poor think again. when I do head work on newer vw's/audi's to set a stretch bolt right you need to use a beam or a dial to watch the pull up a clicker will not do that. then do the strech with a breaker bar. It tells you that in the bently but most guys I have worked with do do it that way. there is nothing wrong with a good old beam. I can't beleave what all bolts on cars today are stretch type bolts. sorry I got alittle off course with my responce.