Makita USA launched a new XGT cordless shear wrench, model GTW01, that’s designed to “give the Steel Erector a cordless option that takes corded tools out of the jobsite.”
The new Makita cordless shear wrench is advertised as being up to 14% faster than their corded tool, and 3.5 lbs lighter than their previous 18V LXT system model.
It features an electric brake, metal gear housing, on-tool LED charge status indicator, and shoulder strap hook.
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The bolt tip ejecting lever is located near the power switch for easier tip disposal.
Shear wrenches like this one are commonly used in metal construction to tighten torsion control bolts. Upon tightening the fastener to its set torque, its head is sheared off. It’s a quick method that helps to avoid overtightening.
- Bolt Size Capacity (A325): 5/8″, 3/4″, 7/8″
- Bolt Size Capacity (A490): 5/8″, 3/4″
- Speed: 17 RPM (no-load)
- 593 ft-lbs max torque
- Weighs 12.2 lbs
- 10-5/8″ length
Makita says that the tool can tighten up to 250 M22 torque control bolts per 4Ah battery charge.
The kit ships with a 4Ah battery, Rapid Charger, inner and outer sleeve assemblies for 3/4″ (M20) and 7/8″ (M22) bolts, a screwdriver, shoulder strap, and tool case.
Price: $2999 for the kit
Makita USA Intro Video
How a Shear Wrench Works
Shown here is an example of a torsion control bolt.
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Shear wrenches have inner and outer sockets. The inner socket has a spline profile and engages with the bolt tip. The outer socket engages with the hex nut.
The outer socket rotates and tightens the nut until the required torque is reached, while the inner socket builds up reaction torque but does not rotate.
When the proper torque or tension is reached, the outer socker stops rotating and the reaction torque rotates the inner socket. The tip of the bolt shears off and is then ejected and discarded.
With a traditional drill, the reaction torque is exerted on the tool body. If you let go of the drill, or if it jams or binds, the drilling or driving accessory will stop moving and the tool will rotate. With a shear wrench, the reaction torque is generated within the tool and exerted on the inner socket.
Thus, in a shear wrench, the outer socket will rotate the hex nut, with the inner socket holding the spline steady until the required torque is met. At this point, the shear limit of the spline tip is reached and it breaks off.
Here’s an animation on how they typically work:
Jared
Is the idea that once you reach the right torque, the portion of the bolt that sticks out past the nut fails and is twisted off?
This obviously isn’t my field and I’m trying to understand how it works. I don’t imagine the tool has any torque settings.
its_jake
Yep- holds the nut still and spins that e-torx type deely until it shears. Undertightening is a problem, and so is overtightening.
Presumably the electric brake just makes it stop when it shears and can spin more freely.
Jared
Cool. Thanks for clarifying!
Koko The Talking Ape
It’s not the other way around? It doesn’t hold the torx tip and spin the nut?
I guess those bolts have to be made pretty precisely.
Thanks for explaining it. Kind of amazing!
it’s_jake
coffee had not yet kicked in. twists thing against other thing. whoopsies.
Stuart
I added a rough explanation at the end of the post, and found a neat animation showing how they work.
jake
Great explanation and video; thank you.
It looks like a good system.
Jared
Perfect! So the outside and inside do spin opposite each other. That’s neat.
Robert
Is that first Makita photo realist? Can you really hold this 12.2 lb tool like that one handed and control the torque it’s exerting to shear through those bolts? I recognize there doesn’t seem anyplace for a second hand to grip, but that pose just doesn’t look ergonomic to me.
Jared
Your comment made me realize I have more questions.
If asked I would have guessed it had an impact mechanism – but obviously not if it spins at 17 RPM. Is it just the friction from the tightening nut against the steel it’s clamping that holds the tool in position?
I presume the outside 12pt “socket” doesn’t spin and there’s a recessed socket that does – or do they somehow turn opposite each other?
Koko The Talking Ape
its_jake explains it. The wrench holds the nut and spins the bolt against it (or the other way around), so exerts a torque a between the two parts. If I understand it correctly, there’s no torque transmitted to the user.
It made me wonder how astronaut tools like bit drivers are made so that they don’t spin the astronaut instead of the screw or bolt. So far I haven’t found any explanations of how they work.
Joe
As always, it depends. But i am pretty sure they just have the astronauts braced or their feet attached to an arm, etc.
Or they strip the screw and they just have to rip the handle off with brute force so they can complete the mission (last hubble service mission)
MM
Yes, that is realistic. There is no reaction torque to the tool because the tool engages both the nut and the bolt. Look carefully at the pic of the tool in use, you can see the splines on the bolts where the tool engages them.
Doresoom
If you look closely at the bottom photo, you can make out both an external and an internal socket. So the tool contains all the reaction torque within its housing.
LeJeune Bolt has a cutaway illustration of how it works in this user manual: https://lejeunebolt.com/lbc/wp-content/uploads/2016/04/S_manual.pdf
Rich Phillips
It depends on your hand strength. As a general statement, you won’t feel the tension bolt tighten. This is a unique tool and its only application is for tension bolts. This is a tool primarily used by steel erector trade.
Alex
They’re called LeJeune bolts (brand name) or tension-control bolts (generic name used by engineers specifying them).
Chris
The e torx is part of the bolt and is designed to break off clean once it reaches a specific foot pounds
I used these in water works projects like water mains quite neat in my opinion
Nathan
Made heavy metal fabrication much faster and safer. It’s interesting to watch installation. And after the top shears. If you just have to you can unwork the remaining nut off and start over but the previous bolt is thrown away.
Interesting I thought there was a cordless tool for this already
Stuart
There’s a heavier 18V version.
Tughom
Didn’t know where to leave this but 2024 Wera Advent calendar should look like:
4043769_1_P_PROD_SPEC_R101099912VerkaufsprospektPDF
Robert
Folks, thanks for the follow-up info. This fastening system is rather clever. Seems to me it reduces the chance of operator error and variability. I saw one application of thousand of bolts that had to be torqued to tight tolerances. Was a big food fight over if the all torque wrenches used were calibrated, if proper torque was set, if operators used other wrenches, etc. These types of torsion control bolts would seem to have been a better way.
Nathan
Yes that’s what they were made for. This wasn’t the first torque control bolt but it’s what has persisted. They are expensive but usually worth it.
fred
Where operator-error can come into play is when the manufacturer’s lubrication on the bolt is allowed to deteriorate via improper storage or aging at the jobsite.
I don’t recall us using this style in our fabrication business – but we had clients specify break-away security nuts for some jobs:
https://www.tannerbolt.com/security-products/security-nuts/security-break-away-nuts
We also did an assembly where frangible bolts/nuts were specified between components.
its_jake
Fred covers it, but maintaining spec’d lubrication is very important. These use torque as a proxy for tension, and dry vs lube, plated vs raw vs stainless etc all have big effects on how much tension a given torque puts on a bolt- this is the “K factor” or “Nut factor”.
Smart Bolts has a neat writeup- this shear wrench will not tension properly if the k factor is not controlled for. which is why, of course, you should buy their product… Sarcasm aside, it’s a pretty neat product
https://smartbolts.com/insights/the-nut-factor-problem
And then there are rotabolts
https://www.jameswalker.biz/our-solutions/our-products/load-indicating-fasteners/rotabolt
Lots of clever solutions to this problem
fred
I should have also mentioned that we had clients who specified Hi-Lok fasteners. These come in a myriad of configurations. Some can be set with hand tools – but we most often used pneumatic guns and ratchets. They work on a similar principle where a 2-part nut (designed with intermediary groove) shears off when the specified torque is reached.
mark
Really enjoyed this shear bolt explanation here! Didn’t even know about these & it’s an interesting method/tech.
mark
I just watch TTC’s (torque test channel) recent video testing bolt torquing myths – anti-seize on bolt threads (therefore lubricating the threads) caused the torque wrench to click at DOUVLE the ft-lbs it was set to. I was pretty surprised at the severity of that change.
mark
Double * 🙄
SamR
Today I learned something new. Thanks.