Dog Leg Side?

[Mephistopholes]

Alright everybody, I need some help here. I'm sure this is probably an easy answer, but I've been scouring this site and can't find it.

My question is: what is the "dog leg side" of a gripper, and how do I determine which side it is on my gripper? All I use are the Ironmind Captains of Crush grippers.

Thanks!

Bobby

[anwnate]

http://www.gripfaq.c...Gripper-Dogleg/

Here's an info friendly site.

(not to imply that the GB is not info friendly...just that there's a lot of good fingertip info at that link)

[Cannon]

Here is a close-up from my gallery:

[Mephistopholes]

Ooooh now I see. I'll have to check that out on my grippers when I get home tonight.

Thanks!

[MalachiMcMullen]

Props for the Faust reference.

[Savage Jake]

i wouldn't pay mind too much about that dogleg if i were you , its just a myth purported by people who are not strong enough to close hard grippers. Just train hard and don't worry about it.

[Cannon]

i wouldn't pay mind too much about that dogleg if i were you , its just a myth purported by people who are not strong enough to close hard grippers. Just train hard and don't worry about it.

Uh, that's a weird thing to say.

Call it a myth if you want (I agree), but put something with some meat behind what you're saying.

The reason I think it doesn't matter is based on my experiments with ratings. On a gripper where there is no uneven mount, it will rate identically no matter which way you orient the gripper.

[macaz]

The non dog leg side is bad luck I think.

Seriously who came up with the term dogleg and the idea that it is mechanically better for the palm?

[Bill Piche]

The non dog leg side is bad luck I think.

Seriously who came up with the term dogleg and the idea that it is mechanically better for the palm?

Pretty sure John Szimanski (RIP) of PDA did. Not 100% sure though. I like putting the dogleg in the palm. Personal preference though.

[Cannon]

The non dog leg side is bad luck I think.

Seriously who came up with the term dogleg and the idea that it is mechanically better for the palm?

Pretty sure John Szimanski (RIP) of PDA did. Not 100% sure though. I like putting the dogleg in the palm. Personal preference though.

It's an interesting habit for sure. I also always set it up the same way. You see this in sports everywhere. Mentally, a routine even as simple as how you place the gripper can help you perform. Think about people taking free throws. People do a lot of random things prior to shooting the ball and it's all about automating the movement and making it familiar. I think this has value even if it's arbitrary.

[daniel reinard]

What Matt said. I put the dogleg in the palm for peace of mind and an auto routine setup. Its just part of the ritual. But I am thinking I will flip that gripper over and make that the routine just to be a weirdo/rebell. That's probably the best way to be a gripper bad***.

[Mephistopholes]

Yeah I kind of figured its really more of a mental prep issue than anything, but I was really just curious. I mean, I've gotten this far without not knowing what the heck it is, so it may be a non-issue for me really, but it's worth knowing about regardless. Just a millimeter short of closing the #2.5 last time I tried, so I've made a lot of progress without knowing about the "dog-leg."

Also, yes, Faust is awesome.

[Wade Gillingham]

I have felt the difference before on a "made in China" gripper. There was such a skew on the dogleg side that it did make a difference which side was in my palm. Now in this case the spring had poor geometry so the difference was pronounced. But it does illustrate that there can be a difference. Yes if you put a gripper in a vice or RGC, the same force will have to be applied regardless of which end is up. However, in the hand things are different. You are fighting other forces like rotational torque on the handles as you bring them together across the spring pack in an unatural ROM for a torsion spring (why do you think they fail at nearly the same spot everytime? ever looked at how far the coils open on the top of a gripper and bind on the bottom?). Your fingers are moving when closing a gripper and your palm is the anchor for the most part. Have I ever felt a difference on a quality gripper?...no, but that doesn't mean there isn't a difference when the gripper is being closed in the hand. I thought enough of it to design GHP grippers so the dogleg is in the palm so you don't have to question it.

[iamsean11]

If you want proof that it doesn't matter which side is in your hand, look to physics. The magnitude of torque is based off of tau=rFsin(theta), where theta is the angle between the force vector and lever arm vector. Being that the angle, force, and length of lever are all the same no matter which handle is in the palm, there can be no difference in gripper difficulty.

[Wade Gillingham]

If you want proof that it doesn't matter which side is in your hand, look to physics. The magnitude of torque is based off of tau=rFsin(theta), where theta is the angle between the force vector and lever arm vector. Being that the angle, force, and length of lever are all the same no matter which handle is in the palm, there can be no difference in gripper difficulty.

I think you completely missed my point. I don't disagree with you but my contention is that this isn't as simple as measuring force in one vector - if it was then the RGC would be a perfect predictor of how hard a gripper is to close and we all know that is not true. My point is there are other forces in bringing the handles together than just the one dimension you measure in an RGC type measurement.

[iamsean11]

If you want proof that it doesn't matter which side is in your hand, look to physics. The magnitude of torque is based off of tau=rFsin(theta), where theta is the angle between the force vector and lever arm vector. Being that the angle, force, and length of lever are all the same no matter which handle is in the palm, there can be no difference in gripper difficulty.

I think you completely missed my point. I don't disagree with you but my contention is that this isn't as simple as measuring force in one vector - if it was then the RGC would be a perfect predictor of how hard a gripper is to close and we all know that is not true. My point is there are other forces in bringing the handles together than just the one dimension you measure in an RGC type measurement.

Wade, I was mainly referring to people saying that flipping a gripper around would change the difficulty of the gripper. And yes, you brought up some excellent points about the feeling in the hand between brands/quality and the way they differ.

[David_wigren]

Wade is spot on. Physics actually predict that there should be a difference. Only way it wouldn't matter was if your hand applied the force straight on each handle until it closes. Unfortunately that is not true since you are bound to cause rotational torque on the handles themselves, and since the handles don't rotate that force will act on the coil, grinding the bottom of the coil into itself, and thereby making it harder.

I've tried to explain this a few times over at IM, but it seems like they only managed to take the first course of high school physics, but never managed to get to the second course of physics It's quite frustrating.

However one could argue that the difference is so minimal that it's pointless to bother about the dogleg. I can buy that argument. But to say that it's a myth or that there is absolutely no difference is just uneducated.

[Mephistopholes]

Well, I tried it out, and I didn't notice a difference. But that doesn't mean that it doesn't make a difference to some people. For example, I do most lifting barefoot, and I notice a difference, but I know others who have tried it and to them it made no difference. It seems negligible.

[iamsean11]

Wade is spot on. Physics actually predict that there should be a difference. Only way it wouldn't matter was if your hand applied the force straight on each handle until it closes. Unfortunately that is not true since you are bound to cause rotational torque on the handles themselves, and since the handles don't rotate that force will act on the coil, grinding the bottom of the coil into itself, and thereby making it harder.

I've tried to explain this a few times over at IM, but it seems like they only managed to take the first course of high school physics, but never managed to get to the second course of physics It's quite frustrating.

However one could argue that the difference is so minimal that it's pointless to bother about the dogleg. I can buy that argument. But to say that it's a myth or that there is absolutely no difference is just uneducated.

David, I am studying theoretical physics and applying for a phd program in physics, so I think I know what I am talking about. Not comparing all grippers, but if you isolate a single gripper, close it both ways, there will be no difference because the same forces will all be applied in both orientations, and this is made manifested by the fact that the gripper closes and contacts each others handle in the EXACT SAME SPOT every time.

This is a very elementary Newtonian physics principle, so don't make it sound like something it is not.

Sean

[macaz]

I’m sure you know your physics but there are some things you are overlooking. The dogleg in the finger side is bad luck. Period.

Also the minute difference in the coil shape between the dog and nondog probably has a very very minute affect in the action of closing. The action in the hand is not even movement on both legs. You are contorting the springs legs differently while you close.

While you are going for your PHD you should do some experiments on this because it would be very cool to see.

[Electron]

I vote for Sean's thesis to be in gripper physics.

[Cannon]

Yeah, Sean, have we ever steered you astray? You'll be famous and published in, like, ones of journals!

[iamsean11]

I’m sure you know your physics but there are some things you are overlooking. The dogleg in the finger side is bad luck. Period.

Also the minute difference in the coil shape between the dog and nondog probably has a very very minute affect in the action of closing. The action in the hand is not even movement on both legs. You are contorting the springs legs differently while you close.

While you are going for your PHD you should do some experiments on this because it would be very cool to see.

Hey Rich, I definitely think you're right about the bad luck! It must be why I cannot take a decent video for my mm0 cert. The main point you mention about the difference in the dogleg and the non-dogleg coils is something I have put some thought into. So try this. If you put a gripper in your hand, such as a #1 or anything easy for demonstration, and attempt a no set close, there is a very small amount of force needed to move it just a little bit. If you flip the gripper around and try it again, the same thing happens, but the interesting point to examine is where the close is taking place. A spring doesn't have to close equally, meaning that it can close more so on the dogleg side coil or vise-versa, but a spring is consistant, and always closes the same way once it has been seasoned. A gripper has a fixed point of origin, like a pendulum or a drafting compass, and this point is where the angle can be measured from. The cool thing to notice is that no matter which handle of the gripper closes, whether it is the handle in the palm or fingers, the angle is consistant, and always correlates to the exact senario if the gripper was flipped. This is also proportional to Hooke's Law for springs, because closing a gripper is a linear function, and can sequentially be shown at every force value throughout the gripper's range of difficulty for both the dogleg coil and non-dogleg coil. The coolest part is that the values will be identical at, for example, 10mm, 20mm, 30mm, etc, and all the way until it is closed!

I will maybe try rigging something up in the lab if I can think of a safe way of doing it, Rich. Also, I might make a video of the physics of the gripper if there is an expressed interest.

I hope that helped.

Sean

[iamsean11]

I vote for Sean's thesis to be in gripper physics.

Yeah, Sean, have we ever steered you astray? You'll be famous and published in, like, ones of journals!

Haha, Matt and Yori, you guys are funny. I just mentioned in a post that if people are interested, I will do a youtube video of gripper physics, and maybe try to build a device in the lab..

Sean

[macaz]

I’m interested. What is your utube channel?