Electronic Torque Wrench from Sears

[Groesbeck Hurricane]

Has anyone bought/used/seen the electronic torque wrench from Sears? It attaches to a standard socket and gives torque readings on a seperate electronic unit. It is supposed to be accurate to +/- 3%. I'm thinking of investing the $150.00 for one, but wanted to know if anyone has used them before?

[caliber60]

Can you provide part # or link? I checked Sears web site. I also went to the store last night, no such item.

[emcon5]

This?

http://www.sears.com/sr/product/summary/productsummary.jsp?BV_SessionID=@@@@1817292991.104 3173483@@@@&BV_EngineID=ccfcadchgeegejicehgcemgdffmdflk.0&vertical=TOOL&bidsite=&pid=00944598000

[cstreit]

Sounds awfully nifty... Maybe there is a light and a beep when you've reached specified torque..

..oooh, or a series of lights from red to yellow, to green as you get closer to the torque...

I want one.

[pwd72s]

looks cool to me...I wonder what's the reading range? My snap-on torgue wrench is too long for many applications...this looks like it'll work on anything I can get a 1/2" ratchet & socket on?

[JWest]

Says 0 to 150 ft-lbs.

[MotoSook]

We use to use a similar product in my old job. It would just give torque value. It used two strain guages. You could buy some really nice ones (in all ranges) if you want to convert the signals from the guage/attachment to the correct units with a meter. It doesn't look like the Sear part has a way to "click", but it could beep. Ours didn;t click or beep...

[paulhagedorn]

Before you go and buy one of these, be sure to check out the warranty on them. The non-electric torque wrench that you set to a level and then torque, when it reaches the specified torque it clicks. Well, it comes with a 90 day exchange warranty so if it messes up, you can get it replaced right there, but it has a 1 year warranty against defects. But, specifically on this warranty, Sears will NOT recalibrate it, just fix it.

[pwd72s]

I dug a bit deeper...1 year warranty, and yes..0-150 ft. lbs.

[Groesbeck Hurricane]

What I like is that it does give audible signals at preset torques. It also turns our existing tools into torque wrenches. It will also give torque in Ft LBS and NM. Specs:

Applying more than 150 ft-lbs will damage the unit. Acetone, MEK and aggressive solvents will damage the unit. Petroleum lubricants will not damage the unit. D not immerse the unit. NEVER put near a magnet!!

Accuracy Range: To 150 lb-ft (200 Nm)
Measurement Accuracy: +/- 3% at 50 to 150 lb-ft (68 to 200 Nm)
+/- 1.5 lb-ft (2Nm) for less than 50 lb-ft (68 Nm)
Meter Electronics: 4 Mhz processor
2000 Hz sampling frequency
Display resolution: 0.1 Lb-ft or Nm from 0 to 165 lb-ft (224Nm)
Modes: Track (Continuous)
Peak (Hold)
Target (Alarm)
Alarms: Tracking, Over-Torque, when meter and sensor become disconnected.

Neato Scale: 9 out of 10????

"Limited One Year Warranty. If this unit fails due to a defect in materials or workmanship with one hyear from teh date of purchase.... The possible need for recalibration of the sensor is considered normal maintenance and is not regarded as a defect. This warranty does not cover accidental breakage or user abuse "

"If the sensor requires recalibration with 90 days of the purchase date, call 1-800-726-7290 to arrange for recalibration free of charge. After 90 days from the purchase date, there will be a charge for recalibration."

[MotoSook]

For 150, buy yourself a nice mechanical T-wrench and forget the digital one. I hated using the one we had at my old job.

[old_skul]

Sounds nice, but at 96 lb-feet (torque value for lugs), there's a +/- 3 lb variance. Is that acceptable? For lugs, sure...but what about my calipers?

[JWest]

there's a +/- 3 lb variance

I just looked up a $250 Snap-on torque wrench and it is good to 4% CW and 6% CCW. Not as good as this one at 3%.

[ChrisBennet]

Originally posted by old_skul
Sounds nice, but at 96 lb-feet (torque value for lugs), there's a +/- 3 lb variance. Is that acceptable? For lugs, sure...but what about my calipers?

I think 3% is pretty normal for a torque wrench, at least the clicker type.
I hate to sound like a broken record but I think torque values, as we generally use them, are a pretty crude measurement of how tight a fastener is. When you remember that something like 80% of the torque is used to overcome friction you realize that fastener condition and the lubricant used makes a huge difference. To put it another way, the wrench inaccuracy is much smaller than the error you introduce when you don't use a new fastener with the lube specified for that fastener.
The fact that wheels and fasteners don't fall off every day on cars makes me think that there is a wide allowable torque range on most fasteners.
-Chris

[Wayne 962]

Torque values are indeed *very* crude. What you are really trying to measure is the total stretch of the bolt - not the torque. The torque is just one way of figuring out the total stretch.

If the nuts are rusted, or the surfaces are dry or lubed, it will significantly change the stretch of the bolt, even though the torque setting will be the same. Plus/minus 3% is probably more than good enough for just about anything. If you want higher accuracy, you wouldn't use a torque wrench anways, but instead a stretch measurement gauge.

I would guess that changes in temperature, lubrication, angle, variations in mechanical wrenches, etc. can probably add up to varying torque values of 20% or more!

The best wrenches are the primative long-bar ones. These never go out of calibration, (because the properties of the metal doesn't change), and they are typically very accurate over time. They are a pain to work with sometimes though...

-Wayne

[Groesbeck Hurricane]

The standard click style wrenches appear to run 4% to 5% accuracy. There is a Snap-On with better accuracy, but it is more than $250.00. And my $250.00 Snap-On torque wrench is part of the problem with my car today. The calibration was WAYYYYYY off. I did not drop it or abuse it after the calibration was checked and given a green light. In case you were wondering, the 60 Ft-lb on my click style read as 38 Ft-lb on my old bar style wrench. But my old bar style wrench is simply impossible to get into small places effectively.

[Bill Verburg]

I agree w/ Wayne I use my stone age age bend the bar ones(1/4" 3/8" and 1/2" versions) far more(100:1) than my fancy electronic and click ones. The only down side is that my old eyes have difficulty reading them w/o glasses. But the same can be said about reading anything(including the dash board in my Audi but not the 911 Thank god for small favors!)

[MotoSook]

Wayne brings up an excellent point about temperature affects on calibration. All the spec that I have seen (measurement engineer for 2+ yrs) are for operation in 60 degrees F. If you're working in your cold garage in the midwest or the heat of Arizona, consider the change in calibration of your wrench.

At the factory, we tried to keep temperature at a constant setpoint (can't recall what it was). All calibrations were done at the same temp.

[Groesbeck Hurricane]

Sounds like I will go out and look for some $27.00 old fashioned torque wrenches. I have a 30 something year old 1/2" that works very well. Hmmmm.

[Wil Ferch]

Few more things...
Chris Bennet is spot-on...what you would *like* to measure accurately is clamping force. ...torque is only a back-door method of indicating where you are, and lubed/ dry, etc etc...makes a big difference. Wayne is *close* when he says you're trying to measure bolt stretch...but this can lead to confusion of words...some bolts are "stretch" bolts ( deformed into their "plastic deformation" region)...and some are torqued to values below that ( so they don't take a permanent stretch). Clamping force is a more accurate term.
What works well is a simple beam wrench that never goes out of calibration...and you can use this as a "calibration check" against your more user friendly click style...just to make sure you're still accurate.
---Wil Ferch