Torque wrench using adapters?

[RICKDIZZLE]

Ok been reading up on this on the interwebs and of course have found a lot of conflicting info...thus I wanted to ask my trusted friends on here. On a project I am working on, I need to torque a few bolts down to 65 inch pounds and 50 inch pounds. They are socket head style allen bolts. I have a 1/4" drive torque wrench, and understand how they work and so fourth. My question lies in adding extensions and or adapters and how that affects final torque values. The allen bolts are in pretty hard to reach locations. Thus I would need to use say a 6" allen shaft to reach them. If I use the 6" allen shaft directly on the torque wrench, will it have an impact on final torque value. Lastly if I run a say a 1/4"- 3/8" adapter then the allen shaft, same question...what would be the impact. I understand Newton's third law, but dont know how extensions impact that law as I think it would add additional leverage. I am by no means working on a scientific exact item, rather a 2 stroke engine for a project. I just would like to learn how it impacts using an extension(s) / adapter on a torque wrench. Thank you guys for your thoughts and input.

 

[Supremeone]

I use an adapter all the time and have never had any issues.

 

[ssn696]

As long as the extension is 90 degrees from the torque arm, no correction needed. Use one hand on the torque wrench handle, and the other hand on the other end to provide a counter force so the wrench rotates the socket extension smoothly without flipping sideways.

 

[fleming442]

This ought to be good. So, you've never had a bunch of extensions together and felt the twist in the ratchet handle? The torque gets lost in the extensions due to torsional load.

 

[GuysMonteSS]

This ought to be good. So, you've never had a bunch of extensions together and felt the twist in the ratchet handle? The torque gets lost in the extensions due to torsional load.

This ^^
From what I remember about torque wrenches the farther you are from the wrench itself,the less torque is transmitted to the socket.
The closer you can get to the final fastener,the better.
The loss might not be much,but in some cases it could be critical.
I would add 5 % to be on the safe side.
Guy

 

[69hurstolds]

Newton's third law: For every action, there's an equal and opposite reaction. Think sway bars.

Extensions don't matter on a torque wrench. Believe whatever you choose, I'm picking science.

If you put 20 lb-ft of torque on those extensions and maintain it, what force is on the other end of the extensions?...20 lb-ft. The whole idea of a torque wrench is to measure applied torque on one end of something that's being twisted. The torque applied to the bolt is going to be 20 lb-ft. until the wrench is released. You're still applying the same torque. You're only measuring applied torque at the head of the unit. Extensions won't ruin it as you're not changing anything, but if you use a crow's foot, then you have to change the distance factor. That becomes a new ball game.

Dirty or goobered threads? You put 20 lb-ft of torque on it and you walk away thinking it's torqued to 20 lb-ft. You would be correct because it resisted movement at 20 lb-ft where you stopped because that's what the "specs" call for. The dirty threads just stopped you from properly stretching the bolt to some clamping force pressure. The dirt helped add to the resistance to turning the bolt, so the equivalent converted clamping force wasn't reached. But you still applied 20 lb-ft of torque. The bolt doesn't care if it's 20 lb-ft or 200 lb-ft of applied torque, it only will do it's job when it stretches to reach the clamping force needed to keep whatever it is in place, along with not exceeding yield.

 

[fleming442]

Myth busted; I stand corrected. Now, a u-joint on the other hand......

 

[83StreetMachine]

I've used an extension with a torque wrench before but for stability don't link a bunch together.

Also, if you can avoid using the long shank Allen key, and use a short one with a properly sized extension, that would be best. Especially when torquing the fastener.

Those long keys work great but they are usually not made of the best materials and twist or break easily. At least that has been my experience.

 

[pontiacgp]

I understand what your concern is. The longer the extension the more twist you will have in the shaft of the extension.

Myth busted; I stand corrected. Now, a u-joint on the other hand......

I will have to remove my

in your other post......I do not like being mislead, once again I am a victim......

 

[Rt Jam]

Extension equals NO change. 69Hurst explains it and so does the video.

If someone has experience where there was a change. I will be betting the angle was not correct or the action was leaning sideways on the fastener (and not rotating it) which changed the torque.


Where I think some of this myth started is when using impact action. When using an impact wrench and too many extensions. The hammering action may not loosen a fastener. Now remove the extensions and it moves. In this case the impacts were lost in the joints. Instead of directly hitting the driver and fastener.
Similar to hammering a nail into the piece of wood. If the wood is held solid, like in a vise. The nail goes in every hit. Hold that wood in your hand or sit it on a foam pad and the nail hardly moves in.