Bolt stretch

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ctwo
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Re: Bolt stretch

Post by ctwo » Thu Aug 09, 2018 1:23 pm

If my snap-on goes both ways, I'll check my lug nuts, and the ones installed by the last tire changer.
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Rich_Carlstedt
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Re: Bolt stretch

Post by Rich_Carlstedt » Thu Aug 09, 2018 1:57 pm

I have to admit I am a bit surprised that this has not been mentioned yet ??
You can use a impact wrench for torquing bolts IF you have a torque limiting extension.
I have used these myself and they are amazing ..as I rechecked the torque provided and it was right on.
So just because a car mechanic uses a impact , does not make it wrong, IF he also has a torque limiter
https://store.snapon.com/Torque-Extensions-C675866.aspx
Rich

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BadDog
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Re: Bolt stretch

Post by BadDog » Thu Aug 09, 2018 2:09 pm

Actually, I did mention them when I referenced "torque sticks".

Just curious, what are your thoughts on the "torque sticks". Do you guys use them?
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EOsteam
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Re: Bolt stretch

Post by EOsteam » Thu Aug 09, 2018 2:34 pm

Don't forget to have your torque wrench periodically calibrated. I think aircraft mechanics calibrate every 1 - 2 years depending upon use.

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Rich_Carlstedt
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Re: Bolt stretch

Post by Rich_Carlstedt » Thu Aug 09, 2018 2:46 pm

Sorry BadDog, I didn't recognize the term you used-"Sticks" .
The shop I was at always called them Torque Limiters...and I learned from them.

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warmstrong1955
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Re: Bolt stretch

Post by warmstrong1955 » Thu Aug 09, 2018 2:48 pm

EOsteam wrote:
Thu Aug 09, 2018 2:34 pm
Don't forget to have your torque wrench periodically calibrated. I think aircraft mechanics calibrate every 1 - 2 years depending upon use.

Easy enough to calibrate your own, if you aren't in the aircraft biz or something that you need to play CYA.
:)
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warmstrong1955
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Re: Bolt stretch

Post by warmstrong1955 » Thu Aug 09, 2018 2:51 pm

We tried some torque limiting extensions, but heavy duty flavor. 325 ft/lbs and 450 ft/lbs.
They varied a bit between different impacts, but nothing unacceptable.
They varied more, by air pressure.
They failed a lot.

Torque wrench, in my opinion, is the way to go.
Today's solutions are tomorrow's problems.

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BadDog
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Re: Bolt stretch

Post by BadDog » Thu Aug 09, 2018 3:05 pm

No worries, "torque sticks" may just be a regional thing. Or maybe an originating brand? Or just convenient usage being a bit more conversational (though less precise) than "torque limiting impact extensions". I added "impact" because (as far as I know) they only work when used with impacts.

And that's pretty much what I thought about them. Probably pretty close and consistent if it's Snapon or comparable, probably not so much if it's HF or the like. Initial quality, time in service, treatment, air pressure, impact power (HF budget vs high torque IR?), all sorts of things would seem to come into play. I've never owned a set, but don't complain if a tire shop uses them as long as they look like quality and not beat up. But I usually stop them before they can get started if I see an impact with only socket or standard extension mounted. And I should just record the conversation one time since it always goes almost word for word the same. It almost always starts with "we always do it that way", followed shortly by some form of "we are professionals and know what we are doing, we wouldn't do anything dangerous". I've seem service managers so angry their face turned red, but I've never yet had one refuse when they realized I wasn't going to accept any other outcome. When it gets that bad, I always wonder if they are going to screw with me, so I retorque when I get home, but at least I don't need an impact to remove nuts from galled studs...
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liveaboard
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Re: Bolt stretch

Post by liveaboard » Thu Aug 09, 2018 6:35 pm

My click type goes both ways; but I think the point of not using a torque wrench for disassembly is that you don't use it as a breaker bar.

I worked in a US auto garage in the 70's. we did all sorts of things, I rebuilt engines and I was just a teenager at the time.
Anyway, I was torquing down the heads on a V8 when my boss gave me grief. "Do you think they use a torque wrench at the factory?" he demanded, knowing well I had no idea, as I'd never been to the factory, but he had.
"Use an impact wrench!"
So I did. I don't remember how many head bolts there were, but it was a lot. Anyway, it was his dime if something broke.
I put on a lot of heads [valve jobs mostly], never had a broken bold, casting, or a leak. I just hit then until the bolts stretched a little.
It sure was fast.

When I work on my own engines, I use a torque wrench!
For wheels on passenger cars, I'm particular because now they're aluminum. Back when it was big old Detroit steel I used an impact wrench.
Not for the tractor, it needs more torque than a 1/2" one can deliver.
Sometimes I use a long bar and a pull scale. Poor man's torque wrench. Luggage scale $6.
In the field with limited tooling, I've used a measured length of bar and hung water jugs of known weight.

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NP317
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Re: Bolt stretch

Post by NP317 » Thu Aug 09, 2018 7:35 pm

When I change wheels at home, I use an electric torque wrench for disassembly.
Then I use the same torque wrench to install, WITH Torque Sticks attached.
https://www.youtube.com/watch?v=LQOa0p4R0z8

Then I double check the bolt torque with my Click wrench,
Never lost a wheel.
So far...
~RN

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BadDog
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Re: Bolt stretch

Post by BadDog » Thu Aug 09, 2018 11:57 pm

I'm thinking I will start being an even bigger a-hole and refuse to let them use torque sticks. I always thought it was going to be off by varying degrees, but that video combined with the comments here make me change my mind about it fitting within my comfort zone. That may be only one video, and I'm sure there are videos showing them consistently +/- some small variance, but it's clearly too easy to be WAY off. They were a cheap brand, but appeared brand new, so had no wear-n-tear unlike the beat up versions I commonly see in tire shops. Oh they're really going to love me now. But taking my money always seems to overcome their frustration enough for them to at least condescendingly do what I require. Particularly given the cost of the tires I buy. They aren't going on a Prius...
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Mr Ron
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Re: Bolt stretch

Post by Mr Ron » Fri Aug 10, 2018 10:36 am

BadDog wrote:
Thu Aug 09, 2018 3:05 pm
When it gets that bad, I always wonder if they are going to screw with me, so I retorque when I get home, but at least I don't need an impact to remove nuts from galled studs...
If the nuts were over torqued at the shop, the elastic limit has already been compromised; what good then would it do to retorque?

Why would anyone use a torque wrench to loosen a bolt/nut?
Mr.Ron from South Mississippi

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