ZRX61
Well-known member
I have 6:
3 Craftsman
2 Lexivon
1 Norbar (now owned by SnapOn)
That covers everything up to 250ft/lb
3 Craftsman
2 Lexivon
1 Norbar (now owned by SnapOn)
That covers everything up to 250ft/lb
Torque Wrench Ranges
- Thread starter oldschoolcraft
- Start date
Wrong. Grip location absolutely does matter on those style wrenches.Oh good. You're back.
For a clicker type or split beam, it doesn't matter where you grip it.
OP
oldschoolcraft
Well-known member
What about stripping the female threads of the thing you are threading the fastener into? I stripped the female threads of my transmission pan by overtorqueing the drain plug bolt.
That's what I think happened to my ****** pan, I overtorqued it two times ago, and it was perfectly fine. And then when I did another drain and fill a few weeks later, the drain plug wouldn't thread back in properly.
Also thank you for the detailed explanation, very interesting!
whateg01
Well-known member
Prove it!
Say more.
For everybody else, digital torque wrenches are basically strain gages. There is no release mechanism. So a digital wrench that measures torque from 5-100ftlbs say, doesn’t do anything at 100ftlbs besides beep and vibrate. My guess is, you could use a 3/8” torque wrench to the limit of the ratchet.
But I could be wrong. Tell me more. If I torque to 80ftlbs with a 3/8” wrench what stops me from turning 180? Would thss as t be over 200ftlbs say? What sets the limit?
whateg01
Well-known member
I have a digital craftsman clicker. It's basically an encoder keeping track of how many times I've spun the knob on the end. So not all "digital" are like that.
Yes you can use it like a breaker bar. You can turn it until the ratchet shears off or the handle bends. You can put a 10 foot cheater bar and a 400 lb gorilla on the end of it...
If you put more than the 100ftlb rated max through the wrench though, like say giving 200 ftlb to turn that fastener 180, you will cause the computer in the wrench to tell you to F**K OFF until it gets sent back for recalibration at a place that can interface with the electronics on that specific wrench. With HF prices, this service may cost as much or more than the wrench.
dnschmidt
Well-known member
In the case of Eclatorq, and I suppose many others, the tool will go into an over range error mode that can only be reset with special software and a special cable. So yes, you can do it, but as they say: "You'll be sorry."
Hohn
Well-known member
Thread engagement is key. If you have enough thread engagement such that it's 2x the diameter of the fastener, it shouldn't strip even in aluminum.
But in thin things like pans, you often don't get enough thickness to do a "proper" threaded joint so you can indeed strip out the female threads.
Drain plugs are one of those things where it's obviously better to risk undertighten a little since the failure mode is just a drip or seep unless it's so loose that it falls out.
Thanks. This is new to me. Appreciate you.
Found this very old thread on the subject with your comments.
Kinda hoping when engineers specify angles, they know what those angles translate to in ftlbs and they would know what wrench would or would not work. Such that they don’t specify a torque and an angle that requires 2 different wrenches.
A torque wrench with angle has both torque and angle so why would you ever need another torque wrench?
I guess being an aircraft person, I’m gonna be on this page. I totally get and respect the notion that k factor has such a huge effect on fastener strain for a given applied torque. Every Hohn said is true and I’ve been at least partly around this block before (we don’t use angles, and all repairs, mods get new or restored hardware).
For me, the negatives of outsmarting the manual outweigh the benefits of skipping the torque wrench. If the fastener is corroded, replace it or remedy it. Ensure the mating surfaces are clean, esp under the torqued hardware, head or tail to try to get as close the factory k values as possible. Then, just follow the torque spec!
This is what I do, not what I’m telling anyone else to do. I clean stuff, a drop of 3in1 on the fastener, rub it in, under the head for screws, all over the nut for bolts, then torque per spec.
Maybe I misread your post here.
What it sounded like was, if you had a TTA spec of 60ftlbs + 180, you probably couldn’t finish that job with a 3/8” techangle wrench. So you’d either just do the whole job with a 1/2”, or you’d do the torque with a clicker, and finish with a 1/2” techangle (or whatever).
Did I misunderstand?
Sorry misread the usernames. Got you mixed up with @dnschmidt
hopefully this answered your question
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Paco Pena
Well-known member
If you are building engines you want high end. For general work I grab the Harbor Freight or equivalent. I have access to all my son's Snap-On torque wrenches but rarely use them.
Paco
Paco
Why can't you do a 60 + 180 with a 3/8 torque wrench with angle?
Cruzan80
Well-known member
Not any of the above people (and I don't own a Techangle), but I did sleep in a Holiday Inn once...
My understanding is that the 60 (guessing ft lbs) would be fine, but if the 180 (guessing deg?) exceeds the maximum torque the wrench is calibrated for, it will freak out the electronic guts and then go into "limp" mode afterwards, until you give it to someone with the magic cable to reset it.
The worry with some people/wrenches being is that the angle portion puts an unknown amount of torque into it, and can exceed max ranges. Or it could be fine, but you don't know until you went "too far" (torque, not angle).
My understanding is that the 60 (guessing ft lbs) would be fine, but if the 180 (guessing deg?) exceeds the maximum torque the wrench is calibrated for, it will freak out the electronic guts and then go into "limp" mode afterwards, until you give it to someone with the magic cable to reset it.
The worry with some people/wrenches being is that the angle portion puts an unknown amount of torque into it, and can exceed max ranges. Or it could be fine, but you don't know until you went "too far" (torque, not angle).
dnschmidt
Well-known member
If you go to 60 ft-lb and then turn an additional 180 degrees you'll be at >150 ft-lb in a heartbeat and that will put the 3/8" wrench into error mode from which at least Eclatorq forces you to have it reset and re-calibrated.
Cruzan80
Well-known member
Again, I don't own one, so this may already be handled by the wrench company...
Is there a warning (light/beep/etc) that you are getting close to exceeding specs? Wondering if it could flash a "warning" light, and also let you know you have already gone X degrees, so theoretically (assuming space/access/etc) you could go up a size and do basic math (total-deg travelled) to finish with a higher capacity wrench?
Snap on has this, yes.
But I’ve learned here 1) it’s best not to go there 2) it’s a do over for the fastener, so either way big waste of time.
Oh I see what y'all are saying. I didn't and still don't know what any of these torque wrench ranges are since I don't own any.
They are similar to clicker ranges:
3/8 5-80 or 100ftlbs
1/2” 20-250ftlbs
To help summarize this thread:
For clicker type torque wrenches most manufacturers suggest the bottom 20% of the range is not super accurate. So the real usable range is more like:
3/8” 20-80 or 100ftlbs
1/2” 50-250ftlbs
The takeaway is, you really need both wrenches to cover the majority of automotive requirements. You can’t/shouldn’t really use your 1/2” torque wrench for 10-50ftlbs. Thats 3/8” territory.
What I brought up is the growing prevalence of Torque To Angle or TTA requirements on automobiles. (note: This is NOT the same as TTY or “torque to yield”, but the two often converge.
There are many practical methods used to meet a TTA requirement. The latest generation of digital torque wrenches are able to measure angles, even if the wrench is ratcheted, using an internal gyroscope.
Another advantage of these wrenches is they are generally accurate throughout their entire range.
One thing to watch out for however (which I just learned) is that the electronic strain gage that measures torque can be over strained. So while their upper torque limit remains consistent with the manufacturers specs, one cannot simply add an additional angle on top of a high torque. Doing so would over torque the strain gage.
Snap On models have a warning buzzer and tone to signal an impending over torque event. But in terms of “Torque wrench ranges”, the effect of over torque may limit the practical range of a digital torque wrench if an angle is specified.
I gotcha. Thanks for that.
whateg01
Well-known member
Pretty sure that was covered earlier and you have it wrong.
Maria, is that you? Didn’t know my wife joined GJ!
It would be SO helpful if you could be more specific. Wrong about everything?
Sorry we didn’t go somewhere fabulous on our last anniversary.
It's a bit difficult to explain. One thing to keep in mind is that most torque wrenches don't actually directly measure the torque applied, they measure the flex at the mechanism, which on most wrenches is off-center, whether it's mechanical or electronic. X amount of flex corresponds to Y torque when the reaction force (your hand) is at the proper location. But when your hand is incorrectly located, it changes the whole equation. In general, moving your hand closer to the head of the wrench will make the applied torque higher than calibrated, and moving it further from the head will make it lower. It changes when the wrench clicks.
Honestly, I wouldn't have believed it either, but back when I calibrated torque wrenches for a living I saw it firsthand.
I've never been able to comprehend why hand placement matters for torque application. I always figured it only changes the human effort to achieve it.
For example, 100 lbs applied to a 2 foot bar is 200 lb-ft of force. 50 lbs applied to a 4 foot bar is also 200 lb-ft of force.
Putting 100lbs halfway down the handle of a 4 foot bar (or at the 2 foot mark) is not the same as putting 50lbs at the end of the same bar?
If not, why?
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richfinn
Well-known member
My take on it is this
You buy a Tech Angle for $600 or whatever "if you work in a shop" and have access to a dealer for the inevitable calibrations etc.
If you fix stuff at home infrequently (not on the clock) use your clicker and an angle gauge which costs about $20.
Take your time and save up for a house/pension instead of buying tools you won't get any return on investment on.
All these threads seem to be about "prepping" for an apocalypse that will never arrive
You buy a Tech Angle for $600 or whatever "if you work in a shop" and have access to a dealer for the inevitable calibrations etc.
If you fix stuff at home infrequently (not on the clock) use your clicker and an angle gauge which costs about $20.
Take your time and save up for a house/pension instead of buying tools you won't get any return on investment on.
All these threads seem to be about "prepping" for an apocalypse that will never arrive
Just my thoughts. Bit more basic than some of the comments here. I don’t own a torque wrench, but have been working on cars, bikes, motorbikes for years, essentilly self taught. Never had a wheel fall off, a sump plug strip or leak. I have stripped threads / snapped bolts though, part of the learning curve.
I do have a couple of years of mechanica engineering study and worked as a design drafty for a bit.
Now I’m a fitter in a manufacturing plant and still don’t use them. We don’t really run high stress threshold stuff, but we don’t torque down gasket flanges on pipework. It sounds pretentious, but I guess I / colleagues have learnt / intuition on what muscle memory will snap a bolt, strip a thread, be good enough. If unsure, soak it in loctite, go until it clicks, go back a quarter turn.
I’ve used a torque wrench three times: twice to do head bolts on an engine. The other time was on a uni-joint on a million dollar pick and place robot. Work order said to check the SS socket head cap screw was tightened to 15nM, badixally aet wrench to 15 and try and undo. It was so tight I put a bar on an allen key to get it undone
For reassembly, job sheet said to liberally apply retaining compound and tighten to 15nM.
Since then, every time I get that job, I just make sure the bolt isn’t rattling around. That much green loctite, it’s not going anywhere.
Am I rough? Yeah sometimes, but my machines aren’t falling apart.
I do have a couple of years of mechanica engineering study and worked as a design drafty for a bit.
Now I’m a fitter in a manufacturing plant and still don’t use them. We don’t really run high stress threshold stuff, but we don’t torque down gasket flanges on pipework. It sounds pretentious, but I guess I / colleagues have learnt / intuition on what muscle memory will snap a bolt, strip a thread, be good enough. If unsure, soak it in loctite, go until it clicks, go back a quarter turn.
I’ve used a torque wrench three times: twice to do head bolts on an engine. The other time was on a uni-joint on a million dollar pick and place robot. Work order said to check the SS socket head cap screw was tightened to 15nM, badixally aet wrench to 15 and try and undo. It was so tight I put a bar on an allen key to get it undone
For reassembly, job sheet said to liberally apply retaining compound and tighten to 15nM.
Since then, every time I get that job, I just make sure the bolt isn’t rattling around. That much green loctite, it’s not going anywhere.
Am I rough? Yeah sometimes, but my machines aren’t falling apart.
You are correct, it is the same if you are talking about, say, a breaker bar. However, a torque wrench is different. The mechanism that "clicks" is not directly at the center of rotation, it is offset. Because of that offset, when you move your hand it changes the length of pull on the mechanism. Remember, the mechanism is not directly measuring torque, it is measuring the force required to make torque. By changing the length of that force, it changes the torque level the wrench "clicks" at.
I'm no artist, but I wish I could make a drawing about it. It would probably help you understand.
Just thought of a visual example: if you took your torque wrench, set it for say, 100 ft. lb., put it on a bolt, and hung a 1000 lb. weight on it directly below the head, would it click?
No one torques a bolt by pressing down directly on the head of the torque wrench.
I'm not saying you're wrong, I'm just not wrapping my head around it.
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Hohn
Well-known member
You'd hope that was true, but you'd be surprised how many engineers have never turned a wrench.
I can think of an infamous example from my early time at my present company in which an MSME-credentialed engineer asked the person next to him "what's a camshaft?"
True story.
It turns out you can have a lot of book knowledge and be utterly useless.
I think partly that's why they keep me around-- to prove that with little book knowledge and mostly practical experience, you can still be utterly useless.
Hohn
Well-known member
If the clicking mechanism was directly at the center of rotation, it would never click, because the moment arm would be zero, and the resulting torque would also be zero regardless of the force applied. As you seemed to understand with your last rhetorical question.
The clicking mechanism only sees a moment-- the product of force and distance. Often this distance is fixed and adjusting the torque set point only changes the force requires to overcome the static friction and activate the click.
Which is why the hand placement does NOT matter. Your hand is applying torque to the outside of the wrench. The internal click mechanism is responding to *reaction* torque-- equal in magnitude (force times distance) and opposite in direction.
The mechanism can't see the constituent components of the input torque, it can only see the reaction torque. Which is why 100lb at 2ft is the same as 50lb at 4ft or 200lb at one foot. It is exactly the same as a bolt not knowing how long a breaker bar you used-- it just sees the total torque and is unable to tell what combination of force and distance produced it.
I just did a quick YouTube search and found this video. I didn't watch the whole thing, I will when I get home from work.
Hmmm, no. Your hand applies a force. The resultant moment at the release mechanism is the key. The device is calibrated to compare the applied torque to the output torque, so hand position DOES matter. Torque wrenches aren't SUPER sensitive tho. The device will work if you grip wherever you want. But it will be most accurate if you grip where the manufacturer indicates.
See here: https://www1.snapon.com/display/231/ToolNews/TechRefs/2008/TorqueWrench08.pdf
Don't love the snarky old know it all vibe (especially this one):
To be fair, this is pretty complicated, not easy to instantly understand. And it seems simpler than it is.
More: If you design torque wrenches for a living, this would probably be child's play. We don't typically analyze how torque wrenches work in engineering school. I think in general, engineers are pretty darned good at understanding how complex things operate. But experience of the sort I suspect @Hohn has is really essential. FWIW, I was the first in my family to go to college. My father didn't graduate from high school (and he was a VERY smart man, and a great engineer). But they always expected me to know absolutely everything and I just didn't and still don't. The youtuber above is overly harsh (disrespectful) in my opinion.
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Hohn
Well-known member
The explanation in the video "clicked" for me and with this style of wrench I would agree that position matters.
In my mind I was thinking more of a split beam style wrench. But now I'm questioning as to whether the split beam would also have hand position matter?
I think the beam parts in the split beam are tangent to the rotating part and may not be hand sensitive.
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Agree it’s not instantly intuitive.
You were right there. You apply a torque to the release mechanism. To satisfy the release mechanism we must apply a force where the manufacturer says because the distance from that point to the mechanism is fixed.
ronkz650
Well-known member
Just to answer the question whether hand position matters to myself, I took the liberty to do my own tests on a few different torque wrenches. All were tested at 30ft/lb
Snap on TQFR100C split beam= Matters a lot. Choke up on the handle and it applies 37ft/lb, put an extension on it applies 25ft/lb
Snap on Atech2FR100 Techangle=Matters, but only a couple ft/lb either way.
Sears Digitork clicker from 1981= Doesn’t matter
CDI 3/8 clicker= Matters, about 4ft/lb each way
Precision Instruments dial type= Doesn’t matter
So I guess the answer is it may/may not matter, but better off not taking the chance.
Snap on TQFR100C split beam= Matters a lot. Choke up on the handle and it applies 37ft/lb, put an extension on it applies 25ft/lb
Snap on Atech2FR100 Techangle=Matters, but only a couple ft/lb either way.
Sears Digitork clicker from 1981= Doesn’t matter
CDI 3/8 clicker= Matters, about 4ft/lb each way
Precision Instruments dial type= Doesn’t matter
So I guess the answer is it may/may not matter, but better off not taking the chance.