How much torque is loss with extensions and swivels

[bowlofturtle]

This weekend I was trying to tackle sway bar end links. Here I am thinking, 15min - 1-hour job. Due to the design and overall lack of space and room, I was forced to use a swivel.


It was a 17mm head nut. I used a snap-on 3/8 impact swivel socket pair up with a normal 6inch extension and then a 3/8 to 1/2 adapter. At the end of that was my trusty IR 2135TI. Still unable to zip it off. On the other side, I was able to get with a wrench and cheater bar.

Yes, the car is old and rusty but still, that impact is able 600ft-lbs of reverse torque if not more. The nut shouldn't be much more than 40-100ft lbs. I assume the whole setup absorbed like 50% of the power. It should still be able to come apart.

The whole thing is now being soaked in PB blaster for another try later this week. A normal deep socket is can fit in the area but the ratchet head is too thick as its frame gets in the way.



Side note- How dangerous would be it be to drive on a car without the front swaybar connected? Its an AWD car, that front bar is VERY beefy. Its a highway cruiser car for the most part.

 

[ondarvr]

There are too many variables to say how much torque is lost. Other than to say it can be significant.

 

[CT8]

I can't give a number on the loss of power through swivels and extensions but it is quite a loss.

 

[Chris142]

The problem is the twist in the tools is more than the tools anvil can spin.if you put say 100 ft lbs with a tq wrench and twisted till it clicked it would put 100 ft lbs on the other end. But you may have to make 3 revolutions of that tq wrench to do it

 

[The motor guy]

I've never had luck with swivels, they always just spin off the bolt head.

 

[ctechbob]

Disconnecting the sway bar will generally give you more grip on that end....but, while I've driven with a rear bar disconnected (it was part of the overall setup of the car and fine) I'm not sure I'd be willing to just disconnect the front and drive around like that. Changing the balance of the car in a big way like that without other modifications would probably lead to something scary in an avoidance maneuver.

 

[Trav]

You had a lot of shock absorbers in the form of torsion bars in that setup. Twisting torque is not how impacts works, it is how strong the mechanism hits directly on the fastener. Look at a 1/2" impact extension and how much thicker it is compared to chrome hand tool ones. It will also absorb some of the force just not as much.
To get the most force transmitted to the fastener the socket should be heavy and as direct to the anvil drive as possible.

This is where guns with big hitting power really shine, I have guns rated at 1400 ft.lb and an old IR231 rated at 450 ft.lb the old IR doesn't stand a chance right? That would be wrong, it has large hammers for its size and will remove bolts the larger rated gun failed to remove. Which sort of indicates to me anyway the torque numbers on the box are basically worthless advertising.
Remove the extensions or use thicker impact rated ones and it should come right off.

 

[Chris142]

Originally Posted by Trav
You had a lot of shock absorbers in the form of torsion bars in that setup. Twisting torque is not how impacts works, it is how strong the mechanism hits directly on the fastener. Look at a 1/2" impact extension and how much thicker it is compared to chrome hand tool ones. It will also absorb some of the force just not as much.
To get the most force transmitted to the fastener the socket should be heavy and as direct to the anvil drive as possible.

This is where guns with big hitting power really shine, I have guns rated at 1400 ft.lb and an old IR231 rated at 450 ft.lb the old IR doesn't stand a chance right? That would be wrong, it has large hammers for its size and will remove bolts the larger rated gun failed to remove. Which sort of indicates to me anyway the torque numbers on the box are basically worthless advertising.
Remove the extensions or use thicker impact rated ones and it should come right off.

I still use the 231 I bought back in the 80's. It seems to have more power than it claims. It will remove budd lugnuts from 18 wheelers.

 

[BMWTurboDzl]

This link is close: https://www.utilityproducts.com/too...torque-values-when-using-torque-adapters


Basically you have to know how far off the centerline your wrench is from the fastener. I'm not talking distance in terms of extension. For example with no swivel the wrench is 0 degrees away from the bolt (ie. it's on top of the bolt) regardless of the length of the extension used. Using a swivel at say at 10 degrees the wrench could be 1/2 inch off the centerline of the bolt or more depending on the length of the extension. At 45 degrees it could be 6 inches or more from the centerline of the bolt.

In practice unless the swivel has a fixed amount of travel (ex, max 10 degrees) you're not going to be able to accurately calculate the required TQ.

 

[supton]

Swivels and extensions can twist, and the torque applied by the impact wrench can be absorbed, leaving little to actually hit the bolt. If you were to use a breaker bar and apply torque manually, there would be no loss, the system would just twist--but with the impact, it's twist and release, twist and release, and it's just not giving that impact force to the nut/bolt.

One winter i noticed my Camry seemed to be rolling in the corners a bit more than usual. I thought gee, I guess It's a Toyota... wasn't until I did a tire rotation that I found a sway bar link had given up the ghost. Would guess I drove like that for at least a month. Obviously the car will roll around, and in the event of a sudden lane change, it may fail to react appropriately. But it's not like it's going to suddenly launch off the road. Cars for a while didn't have swaybars at all. I certainly wouldn't want to drive it very hard, but I bet if you take it out cautiously, find some empty roads and drive to see how handling has changed, that it will be just fine. Might drive more like a Jeep than whatever it is, but hey, Jeeps are still driven on the road and they occasionally make it to their destination.

 

[ARCOgraphite]

Originally Posted by bowlofturtle
This weekend I was trying to tackle sway bar end links. ...

..... How dangerous would be it be to drive on a car without the front swaybar connected? Its an AWD car, that front bar is VERY beefy. Its a highway cruiser car for the most part.


Don't go on the highway with a front bar disconnected and a REAR bar still connected, that will make the car excessively tail happy and a moderate fast lane change will loop you. Thats not good in rush hour. Think "The BIg One" at Daytona cup races..

Around town 35 MPH you should be fine unless its REALLY hilly and the roads are wet.
Again it will be easy to loop the car.

Take her around the block and test it out before going further.

Cars didn't have aniti-sway bars when I was younger.
Anti-sway bars take away the independent suspension. Now the left and right are linked with a torsion bar.

Now you can run lower rate springs and make up for the listing with the sway torsion bar stiffness.

Remember watching old 40's and 50's cop chases with the cars going around the corner listing at 25 degrees!

I think you'll be fine and dandy - if you don't go on the highway.

-Ken

 

[dbias]

Originally Posted by BMWTurboDzl
This link is close: https://www.utilityproducts.com/too...torque-values-when-using-torque-adapters


Basically you have to know how far off the centerline your wrench is from the fastener. I'm not talking distance in terms of extension. For example with no swivel the wrench is 0 degrees away from the bolt (ie. it's on top of the bolt) regardless of the length of the extension used. Using a swivel at say at 10 degrees the wrench could be 1/2 inch off the centerline of the bolt or more depending on the length of the extension. At 45 degrees it could be 6 inches or more from the centerline of the bolt.

In practice unless the swivel has a fixed amount of travel (ex, max 10 degrees) you're not going to be able to accurately calculate the required TQ.


That's what I was wondering. Any attachment that increases the distance from the centerline of the bolt or nut would in effect increase the amount of torque being applied. That's why torque wrenches are not affected by a straight extension but cheater bars or crows feet do change the torque values.
With a swivel on an impact driver I'd say the any slop or play in the swivel will lessen the impact shock of the impact gun.

 

[circuitsmith]

I had an aftermarket front sway bar bracket break on my 1981 Accord.
In hindsight I realized the handling had become twitchy over the previous month or so.
Then one night on a twisty road (Beach Drive in Wash. DC) in a heavy downpour, doing about 35-40 I spun out.
I managed to keep it on the asphalt, rolling backwards.
Also in hindsight I realized the brackets for the front and rear swat bar kit,
being stamped steel and flimsier than the original brackets,
weren't a good combination with the thicker front bar and added rear bar.

 

[bowlofturtle]

Thanks all for the feedback. Going to try again this weekend.

I'm going to pick up some wobble extensions and maybe a semi-deep socket to avoid the impact swivel socket i had on there. I did use the impact and also by hand. A breaker bar under the car on jack stands doesn't have much room.

Aside from that, gotta do the walk of shame to the shop.

 

[slacktide_bitog]

This video shows no torque loss from using an extension. Torque loss through a swivel is mostly because you change the angle

 

[Trav]

That is the whole point, impact guns do not loosen fasteners by twisting torque alone.

 

[Alfred_B]

Originally Posted by slacktide_bitog
This video shows no torque loss from using an extension. Torque loss through a swivel is mostly because you change the angle


I find this hard to believe. The extension is bound to twist depending on the metallurgy and engineering of the extension.

 

[supton]

Originally Posted by Alfred_B

I find this hard to believe. The extension is bound to twist depending on the metallurgy and engineering of the extension.

Newton's third law. In order for any part to twist, whatever force being applied on one side is equal to the force on the other side (just opposite in direction). When the forces are not balanced as such, an acceleration occurs.

If the item is a solid shaft and doesn't twist, it's easy to see that the force on either end would be equal. Let's say instead it's a coil spring. You think, I put some force onto one side and I can't get a lot of force, it just twists. You're right, you can't get a lot of force--but there's some force--and that force has to be equal and opposite on the other side of the spring. Otherwise the spring would not wind up. Or the other end would twist around.

 

[UncleDave]

Originally Posted by Alfred_B
Originally Posted by slacktide_bitog
This video shows no torque loss from using an extension. Torque loss through a swivel is mostly because you change the angle


I find this hard to believe. The extension is bound to twist depending on the metallurgy and engineering of the extension.


I dont because they aren't measuring the rotational input at the user end- only the driven end ft lb which isn't going to change.

More degrees of rotation will be required to get the same ft/lb

 

[Alfred_B]

When it twists, the force applied is converted to heat. I find it hard to believe that the extensions do not twist.