Snap On TechWrench

[The Critic]

I want to purchase two Snap-On Techwrenches-- one in the 3/8" drive size and one in the 1/2" drive size. I understand that they are pricey, but I like the idea of being able to see how much torque I have applied to each fastener. Does anyone have any experience with them?

http://buy1.snapon.com/catalog/item.asp?...amp;dir=catalog
http://buy1.snapon.com/catalog/item.asp?...amp;dir=catalog

Thanks.

 

[benjamming]

Do you really understand how pricey that is?
What is wrong with a split beam torque wrench such as PI?
Are you training to be an aircraft mechanic?

 

[tom slick]

You can buy whatever you want but what's wrong with a good clicker? Clickers are good enough for even the most critical parts in $6M jet engines. That techwrench is not inherently more accurate and do you really need an SPC output? Going to do a six sigma analysis of lug nut and drain bolt torques?

What are you going to do 6 years from now when the electronics quit in your lightly used techwrench?

 

[jdeare]

$700+ for 2 battery powered torque wrenches. Personally I'd invest in 1 good non-battery powered wrench and either an adapter from 3/8 to 1/2 or the other way, or else 2 sets of sockets in either drive size.

I have a Snap-on from the 50s that my Grandfather left me when he died. Still works great. I wonder what the planned lifetime of the electronic torque wrench is?

Anyway, it's your cash... but it could certainly be spent more wisely.

 

[jcwit]

Its called more money than cents!

 

[alreadygone]

All of the above.

Bob

 

[Vikas]

I think he should invest his money in a good alignment machine, like Hunter. So that he will NOT have to take his friend's car to Pep Boys

What is with TheCritic? Last time, he wanted to buy Genesys scanner ($$$$) but came to his senses and picked up a lowly Actron/Innova.

Look who is talking though, I picked up the gearwrech flex set even though I have not wrenched anything seriously in years! I know the attraction to good tools.

- Vikas

 

[The Critic]

I should have made it more clear in my original post. I have absolutely no intention of paying $700 for two torque wrenches.

If I do decide to buy a techwrench, it will be new or near new from eBay for $225/wrench, if not less. I plan to sell my useless Precision Instruments split-beam wrench to cover part of the cost.

I definitely don't need such a high-end wrench, but then again, I like owning nice tools, even if I do not fully utilize their capabilities. So, I'd be interested in hearing more about your experience with the techwrench if I you own one.

Originally Posted By: Vikas
What is with TheCritic? Last time, he wanted to buy Genesys scanner ($$$$) but came to his senses and picked up a lowly Actron/Innova.


The Equus 3140 was an impulse buy. I was searching on google and found a guy on the F150 forum who was selling his, so I bought it. At $60, I figured that I couldn't go wrong.

 

[doitmyself]

Why do you refer to your Precision Instrument split beam wrench as useless?

 

[The Critic]

Originally Posted By: doitmyself
Why do you refer to your Precision Instrument split beam wrench as useless?

Although the wrench is rated for 20-100 ft-lbs, it doesn't feel very accurate below 35 ft-lbs. The PI tech told me that the wrench should be accurate anywhere in the 20-100 range, despite what the others have told me.

The main reason why I purchased the PI wrench was for drain bolts and spark plugs, most of which have torque values in the 20-30 range. The tech told me that the wrench should be accurate in that range, at least from how I interpreted what he said. But when I went to install my spark plugs, it felt like the wrench was not clicking when it should have.

 

[TooManyWheels]

Originally Posted By: The Critic
[ it felt like the wrench was not clicking when it should have.


You know what I'm going to say don't you?

If you have a calibrated wrist, why did you waste the money on a psuedo-accurate wrench?

Have you checked it, or had it checked, for calibration? Surely they could modify it to match your wrist...

 

[The Critic]

Originally Posted By: TooManyWheels
Originally Posted By: The Critic
[ it felt like the wrench was not clicking when it should have.


You know what I'm going to say don't you?

If you have a calibrated wrist, why did you waste the money on a psuedo-accurate wrench?

Have you checked it, or had it checked, for calibration?


I wasn't going to crack a head to find out. I'm sure you would have felt the same if you were in my situation.

Anyway, I tightened a lug nut to 50 ft-lbs with the torque wrench. My friend brought over his beam type Craftsman and checked the bolt-- it measured out to 50. So I know it's accurate-- at least in the middle of the specified range. Perhaps I'm worrying about nothing then.

 

[TooManyWheels]

I can certainly understand not tightening a bolt beyond what you are comfortable with. But as you suggested, it may not be that accurate in that range, in which case it would be the wrong choice of tool, not a design or manufacturing defect.

 

[doitmyself]

I got that same feeling when I used my 1/4" Techwrench for the first time on a transmission pan install (10 lbs., gasketed), but I find thick gaskets to be kind of squirrely that way.

I would test your wrench in a vice on a nut/bolt and compare it to a known accurate wrench before tossing it out. My 3/8 PI works fine down to 20 lbs. Maybe you got a dud?

Measuring torque by twisting motion can be off +/- 30% (the general rule of thumb on engineering forums) due to many, many variables REGARDLESS of wrench style.

All of the mfg. that I spoke with said their wrenches "should" be within spec.(+/- 2-4%)at 20 to 100% of scale. Some people "say" they are at their best accuracy in the middle of the scale.....not negating the first sentence.

IMO, the Techwrench is just a different mode to measure torque compared to other styles and each have their pros and cons, but at this (our) level, the accuracy between them probably isn't that significant (my opinion).

Using a vibrating techwrench does take some getting used to, compared to a clicker. There's a big tendency to over-pull and they calibrate the vibrator to go off a few percent low to compensate. They are sweet, but I handle mine (my workplace's) with kid gloves. The difference of using a Techwrench is kind of like using a clicker for the first time when you only used a bending beam style before....well, maybe not that great. Seeing a digital number makes you think it is more accurate.

Finally, those must be some beefy spark plugs in cast iron heads if they require over 20 lbs. torque!

Take care.

 

[tom slick]

You bought the wrong wrench in the first place, as you already know you shouldn't use a 20-100 ftlb torque wrench below 36 ftlbs (20% of range). I don't understand the "need" to jump up to the most expensive unit you can find that isn't any better at what you'll use it for. You don't need that much accuracy for anything you are doing to a car now or in the future.

You can't accurately check torque by torquing a fastener then using another torque wrench set to the same amount. static friction makes the prevailing/break-away torque much greater. All you checked is the lug nut was about as tight as you thought it was.

 

[The Critic]

Originally Posted By: tom slick
You bought the wrong wrench in the first place, as you already know you shouldn't use a 20-100 ftlb torque wrench below 36 ftlbs (20% of range). I don't understand the "need" to jump up to the most expensive unit you can find that isn't any better at what you'll use it for. You don't need that much accuracy for anything you are doing to a car now or in the future.

You can't accurately check torque by torquing a fastener then using another torque wrench set to the same amount. static friction makes the prevailing/break-away torque much greater. All you checked is the lug nut was about as tight as you thought it was.



The PI person told me that the 20% of scale was of 0-100, so the wrench is fully accurate between 20-100. Perhaps I should have known better.

No, I did not use another click-type torque wrench to check the torque. I used a beam-type.

 

[doitmyself]

Originally Posted By: tom slick
You bought the wrong wrench in the first place, as you already know you shouldn't use a 20-100 ftlb torque wrench below 36 ftlbs (20% of range). I don't understand the "need" to jump up to the most expensive unit you can find that isn't any better at what you'll use it for. You don't need that much accuracy for anything you are doing to a car now or in the future.

You can't accurately check torque by torquing a fastener then using another torque wrench set to the same amount. static friction makes the prevailing/break-away torque much greater. All you checked is the lug nut was about as tight as you thought it was.


tom slick, this is how Precision Instruments, Snap On, and ALL manufactures state wrench accuracy: "Accurate within 4% of reading from 20% of full scale to full scale."

CDI..."Accuracy: ± 4% clockwise ± 6% CCW of indicated value, from 20% to 100% of full scale.

It's 20% of FULL scale, not 20% of range. Many clickers have markings below the 20%, ie 20 lbs. in this case.

Critics 100 lb. ft. wrench is accurate between 20 and 100 lb. ft.

You are right about break away torque. You could roughly compare two wrenches by torqueing a lug nut up a few times, marking it with a sharpie, then loosening and repeating it with the other wrench.

 

[GMBoy]

Don't worry critic - get what YOU want. I've been known to spend insane amounts of money on tools when I could have gotten by cheaper. Do I regret it? NO! Good tools are lifetime investments. Would I pay that much for a Snap on digital torque wrench? No, my craftsman's are fine and are calibrated every so often.

 

[benjamming]

GM,

I understand your statement, however, posting like The Critic has here can often save expenditures that will later be regretted. And it is on that thought, that I come out against this purchase now that we know the reasons behind it.

Critic,

Don't take this the wrong way, but it is my opinion that TooManyWheels & doitmyself are spot on. Going by wrist feel is downright silly to put it bluntly. However, if you feel your PI is garbage, the USPS/UPS/Fed-ex man will gladly pick up your garbage & deliver it to me.

We use PI torque wrenches at work for nuclear applications. They calibrate/certify fine. I assume that your TW was bought new & came with a certificate of calibration? If not, you may want to look up http://www.teamtorque.com/.

 

[JOD]

Originally Posted By: benjamming
GM,


=
Don't take this the wrong way, but it is my opinion that TooManyWheels & doitmyself are spot on. Going by wrist feel is downright silly to put it bluntly...We use PI torque wrenches at work for nuclear applications. They calibrate/certify fine.


For auto applications I really think that completely ignoring 'wrist calibration' is a little short-sighted, and frankly, a bad idea.

Keep in mind, I own 3 torque wrenches, and yes, I use them on occasion. That said, I've seen a lot of stripped bolts on lower torque applications (bicycles, mainly) by people blindly following the wrench.

Most often, the culprit isn't the wrench itself but the condition of the mating surfaces. In an aerospace environment, a new fastener going into virgin, cleanly tapped threads is an ideal situation--and even then, there's a high degree of variability (upwards of 30%). That rarely exists in a car. Add in the lubrication properties which greatly affect that actual torque a bolt is receiving, and the margin for error can quickly grow to the 50-100% range (or more).

I'm not saying 'don't use a torque wrench', but I think you have to be aware of its limitations, regardless of its cost.