terminator Posted May 8, 2003 Share Posted May 8, 2003 How do you know it got harder? Maybe you just got weaker for a bit? :stuart Bill, I had a #4 that I got well under 3/8" with three fingers no chalk at the store where I bought it. It kept getting harder from there, so I sent it to Heath to get his opinion. It has kept getting harder and harder. If you would like to try it to see if maybe we're getting weaker I'll send it to you. It is now a brick. Quote Link to comment Share on other sites More sharing options...
Roark Posted May 9, 2003 Share Posted May 9, 2003 Car suspensions (springs) which 'bottom out' under load would be different than those springs which are only worked mid-range, right? Quote Link to comment Share on other sites More sharing options...
Bill Piche Posted May 9, 2003 Author Share Posted May 9, 2003 Possible that I got weaker. But, I had to go up in straphold weight before I could shut it again. Trust me, it got harder. And the #4 went from no set parallel lefty, to no set no move lefty over the course of a few weeks. I guess I am wrong and crazy, so is Terminator, and so is Tetting....... I already know you and terminator are crazy! I believe you. It's just not the norm IMO that a gripper would get harder. Quote Link to comment Share on other sites More sharing options...
Bill Piche Posted May 9, 2003 Author Share Posted May 9, 2003 How do you know it got harder? Maybe you just got weaker for a bit? :stuart Bill, I had a #4 that I got well under 3/8" with three fingers no chalk at the store where I bought it. It kept getting harder from there, so I sent it to Heath to get his opinion. It has kept getting harder and harder. If you would like to try it to see if maybe we're getting weaker I'll send it to you. It is now a brick. What do you think causes this? Quote Link to comment Share on other sites More sharing options...
Bearcat 74 Posted May 9, 2003 Share Posted May 9, 2003 I figure it is how the spring is tempered, or just the spring material itself. I'm not an expert on this stuff though....... No, it is not the norm, I'm just saying it is possible. Quote Link to comment Share on other sites More sharing options...
terminator Posted May 9, 2003 Share Posted May 9, 2003 How do you know it got harder? Maybe you just got weaker for a bit? :stuart Bill, I had a #4 that I got well under 3/8" with three fingers no chalk at the store where I bought it. It kept getting harder from there, so I sent it to Heath to get his opinion. It has kept getting harder and harder. If you would like to try it to see if maybe we're getting weaker I'll send it to you. It is now a brick. What do you think causes this? Some materials tend to harden upon cold working. I suspect as Oldguy said a while back that it depends on the material properties at the start. If a spring is not completely tempered and the alloy has a tendency to "work-harden", the gripper will get harder. If a spring is already at its full potential there's only one way to go....down. I'm pretty sure that's what happened there, it work-hardened. BTW, I went from feeling like superstud that day to superdud later that afternoon. That's why I sent it to Heath.....he's so much stronger than me on grippers (righty at least ) I wanted to make sure it wasn't just me "fading". The gripper continued to get harder and harder everytime he used it. It is a nice paperweight or chest crusher now. That was the day after Heath went back home after Christmas. It sure would have been funny if he were still there......he would have picked up that #4 before me and just slammed it shut. The guy would have bricked his shorts for sure. Quote Link to comment Share on other sites More sharing options...
Tom Black Posted May 9, 2003 Share Posted May 9, 2003 Some materials tend to harden upon cold working Merely moving a spring through its intended range doesn’t fit the definition of cold working as I understand it:“COLD WORKING Plastic deformation, such as rolling, hammering, drawing, etc., at a temperature sufficiently low to create strain hardening (work-hardening). Commonly, the term refers to such deformation at normal temperatures.” From: Metal mart Unless you are hammering the spring of that gripper in frustration then I don’t think its cold working (but I admit I’m not sure what’s included in the “etc.” above, but the key words are "plastic deformation," the metal has to be deformed in some way.) Quote Link to comment Share on other sites More sharing options...
Bill Piche Posted May 9, 2003 Author Share Posted May 9, 2003 I figure it is how the spring is tempered, or just the spring material itself. I'm not an expert on this stuff though.......No, it is not the norm, I'm just saying it is possible. This won't change my mind. You are still one crazy mo-fo. Still not as crazy as Terminator though. Quote Link to comment Share on other sites More sharing options...
terminator Posted May 9, 2003 Share Posted May 9, 2003 Some materials tend to harden upon cold working Merely moving a spring through its intended range doesn’t fit the definition of cold working as I understand it: Ah yes, very true Tom, BUT if the spring in question is already working outside of maximum permissible bend radius (which it is) then maybe some plastic deformation is going on at a microscopic level. It was a theory which seemed to make sense on my part to explain a very curious instance. Perhaps that is the most clever marketing technique ever.....a #4 gripper that you feel is very closeable then gets progressively harder. I think people would get suckered into that everytime. Seriously, if that #4 stayed as easy as it felt that first day I never would have certified on it. It would have just opened up too many questions, etc. Quote Link to comment Share on other sites More sharing options...
Tom Black Posted May 9, 2003 Share Posted May 9, 2003 Hmmm…here’s a quick thought… You bought this in a store and tried it there. Quite likely other people had been trying the gripper in the store as well, but it is very unlikely that they were moving the handles as far as you can/did. Perhaps the spring formed some type of hysteresis effect in which it was hard for the shorter range that it was usually subjected to but once broken beyond that range by you then it seemed easier than a “normal” #4. An interesting side note, in the York barbell store I tried a #4 there that was sitting on the counter. It did seem oddly “easy” too me and I commented to the guy there that it felt "easy" and got a funny look. I am convinced that I was right and that gripper was a bit easier than normal compared to my other #4's (I have two). I think it was seasoned, but as I said above, maybe it was only seasoned for the first part of the close. Quote Link to comment Share on other sites More sharing options...
Patrik_F Posted May 9, 2003 Share Posted May 9, 2003 Hehe, the hardening theory is a great one. I will adopt it to my training right away, whenever I cant close a gripper I used to close I will convince myself that it must have gotten harder But seriously, the hardening thing is for real. If a gripper can get easier with usage it can also get harder. It has happend on at least one of my grippers. Quote Link to comment Share on other sites More sharing options...
Sybersnott Posted May 9, 2003 Share Posted May 9, 2003 So Heath admits to getting weaker! So does terminator! Who else?? Ha ha... looks like I still have a chance at that #4!! Quote Link to comment Share on other sites More sharing options...
The Mac Posted May 10, 2003 Share Posted May 10, 2003 Tom, Surely putting a squeeze on a torsion spring gripper IS deforming it?? Quote Link to comment Share on other sites More sharing options...
Tom Black Posted May 10, 2003 Share Posted May 10, 2003 Surely putting a squeeze on a torsion spring gripper IS deforming it?? It has to be plastic deformation, from the metal website: "PLASTIC DEFORMATION Permanent distortion of a material under the action of applied stresses." If the spring was permanently distorted it wouldn't be a spring. Quote Link to comment Share on other sites More sharing options...
terminator Posted May 11, 2003 Share Posted May 11, 2003 Squeezing a spring that's coil inside diameter is in serious violation of a wire's minimum bend radius is causing excessive stress to the material. Which I beleive could possibly be deforming the metal. No hysteresis or blah blah can explain away the fact that this gripper got much harder. End of story. Quote Link to comment Share on other sites More sharing options...
Bill Piche Posted May 11, 2003 Author Share Posted May 11, 2003 And there's the bell... Terminator takes a left jab via deformation. Black counters with a definition. Terminator.... Quote Link to comment Share on other sites More sharing options...
Rick Browne Posted May 11, 2003 Share Posted May 11, 2003 Check out this "professorial" statement Metal fatigue is caused by repeated cycling of the load. It is a progressive localized damage due to fluctuating stresses and strains on the material. Metal fatigue cracks initiate and propagate in regions where the strain is the most severe The process of fatigue consists of three stages: A) Initial crack initiation B) Progressive crack growth across the part C) Final sudden fracture of the remaining cross section. KA-BOOM....... Busted Gripper Quote Link to comment Share on other sites More sharing options...
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