Gerber slide out plier force compared to butterfly opening pliers

[Raukodur]

Does the slide out plier design of Gerber affect the amount of force the pliers exert? Someone on these forums mentioned that the splay of the handles is less with this sort of design, and so in theory that would allow you to squeeze harder on the handles and exert more force with the pliers...is that the case?

[smiller43147]

Guess that depends on what you compare them to.  Some butterfly MTs open quite wide.  The Spirit, on the other hand, has a comfortable gripping range.

[Vidar]

What leverage you get basically depends on the length of movement you do compared to how much the jaws move because of your movement. (That goes for compound pliers too).

Normal pliers are just two pieces where the connection is the fulcrum point. Both the handles and jaws rotate around this, and any change in angle between the handles cause an equal change of angle between the jaws. How far the handles can spread is not a factor for the leverage with this classic plier design.

I believe Gerber lines up the handle fulcrum on the same axis as their jaw fulcrum so the same logic applies. Thus the leverage will be the same as for a normal plier or Leatherman. That other pliers might be able to spread even more does not affect the leverage.

If you want to increase leverage with pliers either put what you want to grip or cut closer to the fulcrum or get a grip further out on the handles. (From that one can also conclude that pliers with long jaws will have lower leverage on the tip than short jawed ones everything else being equal).

From a human standpoint the handle distance does affect how hard you will be able to grip, but that factor will be the same for all pliers with a simple fulcrum. The easiest human trick to increase gripping power is to reverse your grip on the handle. That brings your thumb root and stronger fingers up the handle where they are more effective.
 

[gerleatherberman]

Edit: got beat to it.

[Lynn LeFey]

I haven't scientifically tested this or anything, but I think this has to do with the size of the hand of the user.

An MP400 is fairly small splay, and fairly short. A person with small hands might get their highest grip force from that. Whereas someone with big mitts for hands might be able to apply more force with handles that splay somewhat more, and are longer, even with a corresponding longer plier head, for instance on a MUT or Surge.

One can't simply look at the tool itself when trying to determine optimal performance, I guess is what I'm saying.

For ME, with medium hands, yes, lower handle splay (to a point) seems to get me better grip force. The MP400 and MP600 are great, the older 'Mr. Pinchy' Multi-plier is just a bit TOO small at full closure for optimal grip. The level of the splay on the original Leatherman PST is great for a butterfly style. The Wingman is... uhh... not. WAY too wide. Most butterfly style fall somewhere between those two.

Here's a pick showing various tools' splay. Left to right: Multi-Plier, MP400, MP600. PST, Wave, and Kick.


The difference in the splay between the MP600 and PST is actually pretty minimal. I wouldn't call any of these bad, except the original multi-plier, as I mentioned, is TOO small for me to get my best grip when the plier jaws are fully closed.

Hope this helps.

[Vidar]

Here's a pick showing various tools' splay. Left to right: Multi-Plier, MP400, MP600. PST, Wave, and Kick.

Ah - I didn't take the difference of fully closed positions into account. Sometimes theory gets the better of me

Considering that and human factors I would say closed position down to say 30-35mm or so is better for utilizing a hands optimal gripping strength - somewhat variable with hand size as Lynn says.

[Sam Lim]

Another major plus for gerber pliers. Their cutters are away from the bolt gripping area. More teeths can be utilised so more grip. For leatherman, their cutters are like 1/4 into their bolt area. Making gripping larger bolts difficult.

[gerleatherberman]

I would like to add that Gerber's sliding system makes for less points of possible failure as well. The pressure is applied inside of the handle frame and the opposite pressure exerted on the frame pins is quite low. LM has a lot of pressure on the two bolts connecting the jaws. Vic has a lot of pressure on the rivets connecting the jaws and the stop tabs. Gerber has the least force lost due to flexing from my experience as well.

[Lynn LeFey]

I would like to add that Gerber's sliding system makes for less points of possible failure as well. The pressure is applied inside of the handle frame and the opposite pressure exerted on the frame pins is quite low. LM has a lot of pressure on the two bolts connecting the jaws. Vic has a lot of pressure on the rivets connecting the jaws and the stop tabs. Gerber has the least force lost due to flexing from my experience as well.

Most of the time, the break is at the jaw, not the handle sides for pliers. Not that it's NEVER the place where the handles connect to the head on butterfly style, or even sometimes the main pivot, but MOSTLY its a plier jaw.

I reference 'The Great (broken) multitool thread'...
https://forum.multitool.org/index.php/topic,9605.0.html

[Vidar]

Gerber has the least force lost due to flexing from my experience as well.

I'm not sure where those forces would be lost? All solid materials flex to some degree. The force you apply to the handles will be matched, with leverage, at the jaws regardless. There is no other stop but the jaws to provide equal and opposite forces for your pressure on the handles. (Unless too much force for the handles to resist or spring back from. Then you do permanent damage instead).

Consider a solid bar of steel and a suitably strong steel spring. Hang up both from a weight then connect a 1 kg mass to the end of each. Disregarding the weight of the bar and springs themselves the weight will read 1 kg for both even if the spring flexes at first. Once it has reached its equilibrium position it holds up 1 kg just as good as the solid bar.

Flexing handles are certainly less confidence inspiring though, and personally I think flexing feels less precise and not as well made. On the flip side if they are very sturdy indeed I start thinking that it could have been made lighter so I would have less to carry around. There is just no pleasing me

[gerleatherberman]

I am terrible at explaining things. Comes with being dyslexic. I knew I shouldn't have even replied.  

Let me try to clear up what I wanted to say.

Having the connection points of the pliers inside of the handles, instead of at the far ends, makes the tool a bit sturdier.
Stick a 3/8" steel rod in the large gripping section of the jaws on a LM, Vic, and Gerber mp600. This will minimize the flexing in the needle nose tips. Squeeze hard and watch the handles closely and you'll see what I mean.

I hope that clears up what I was trying to convey.

[Vidar]

I hope that clears up what I was trying to convey.

If what you were trying to convey was that Gerber handles has less give to them, and that is due to the support inside which is further back in the handles, then yes If not, then no  And there is always a more than fair chance that I'm just lost somewhere all on my own.

My point was just that the forces at the jaws remains the same even with some handle flex.

Edit: Smurf - that last sentence was short and concise - why didn't I just write that the first time? 

[gerleatherberman]

I guess in my head, I had sort of pictured a lever pivoting a fulcrum, and a lever with less 'give' would transfer the movement  over the pivot better with less effort. 
You're quite right and I have neglected to think what I wrote thoroughly enough.
I feel like an idiot, because once the force of the movement overcomes the flex in the lever, then the same energy would be transferred anyway. Thanks for the explanation! 

I may need to go back to school again. I have contradicted myself and will shut up now.

[Vidar]

I guess in my head, I had sort of pictured a lever pivoting a fulcrum, and a lever with less 'give' would transfer the movement  over the pivot better with less effort. 

I understood where you were coming from with that. Intuitively it certainly feels that way, and I feel like a stiff handle is better from a pure user feedback perspective. A handle with give just feels more mushy and like you're having less control. 

On a more general note various characteristics often boil down to design choices rather than technical implementation: Leatherman/ Victorinox could clearly have a stiffer handle if they wanted too, but price and size/ weight got higher priority. Likewise if Gerber has a stiffer construction by nature (I'm not saying they do) they might have chosen to take that out in the form of using less material and reducing price/ weight instead of having a stiff handle.

(There is one curious detail on Leatherman Wave that further points to the flex being quite deliberate and measured. If you press down hard then the knifes/ file/ saw topmost parts collide with each other and makes further bending hard. That seems like a self-protect stop design preventing grips from getting hard enough to do permanent damage - or happy coincidence? ).

[gerleatherberman]

 

[Wspeed]

Very nice write up everyone