Creating an epic CoC#3.5 - Spring transplant

[Alex K]

Hello guys! Recently I received a bunch of older used CoC grippers from 2009. Among them was a CoC#3.5 with a larger spring than on modern 3.5s by a few millimeters. The rating of this gripper was pretty high, around 183, despite not having a deep mount at all (far from flush). I was thinking of moving this spring to my other CoC#3.5 from 2012 (with the much sharper knurling compared to new CoCs), which is basically in new condition, and mount them so that the gripper would rate closer to 185, but this task seems to be hard to achieve without damaging the handles of the gripper. 

Do you guys happen to have suggestions on how to do this? I was thinking of getting some sort of PVC pipe, put the handle in there, lock it in place by tightening the whole thing with hose clamps, get the spring hot with some candle flame or something similar (so that the glue would also heat up), and try to twist the handle loose.

[acorn]

I was never successful at removing handles from a CoC gripper. It could be done with higher heat than I was willing to use but would likely ruin the springs temper and it would have to be re-tempered. A controlled process not really for at home work. Anything over 300F could change the spring temper. 

[John Knowlton]

I would check with Iron Mind To see what they suggest

[John Knowlton]

I Was just thinking What if you heat up the handle up and try and pull it off that way. Do you aluminum will get hot faster than the steel

[Alex K]

Do you guys think maybe some epoxy-dissolving solution could be of use? 

[Alex K]

Also, does anybody happen to know the steel type used in GR8-Springs, or potential tempering processes performed with them? Depending on the steel grade it could vary a lot 

[acorn]

8 minutes ago, John Knowlton said:

I Was just thinking What if you heat up the handle up and try and pull it off that way. Do you aluminum will get hot faster than the steel

The aluminum also dissipates the heat faster than steel.

[Fist of Fury]

I just removed them with a heat gun and the spring is the same as before. I know that because that spring was right at my max at the time. So it was easy for me to feel.

I took a long time tho, just using a cheap heat gun.

[Alex K]

9 minutes ago, John Knowlton said:

I Was just thinking What if you heat up the handle up and try and pull it off that way. Do you aluminum will get hot faster than the steel

I just tried to do so with a candle, probably not enough heat overall. I might try to boil it somehow and pull it off or twist it! The idea is great though, heat through the handle would make more sense!

[acorn]

8 minutes ago, Alexander Koss said:

Do you guys think maybe some epoxy-dissolving solution could be of use? 

I'm not aware of anything that would do this. Epoxy is pretty tough stuff.

[acorn]

Good luck on your project

[Alex K]

Just now, Fist of Fury said:

I just removed them with a heat gun and the spring is the same as before. I know that because that spring was right at my max at the time. So it was easy for me to feel.

I took a long time tho, just using a cheap heat gun.

I have toyed around with so many steel spring grippers and heat in the past, changing resistances and so on... but this tempering thing got me thinking now. I believe I never really reached the temperatures at which the tempering could be neutralized, I probably went to around 150-200°C max (like 300-400F)

[Climber028]

Tempering can start as little as 300F for some steels, but a lot of epoxies will give way around 250 to 275F so if you're careful it will work. A candle might have a high enough temperature but likely lacks the required energy to accomplish this. Would be easier to just use a real torch kept at a distance to remove it. 

If you aren't already into metallurgy or black smiting, I'm going to say the average person had roughly zero chance of ever tempering something correctly, time, temperature, and type of steel are all important variables that need to be controlled. 

 

People are also always mixing up tempering and annealing, and also conflating toughness, hardness, and ductility with no idea which one of these makes a spring more or less difficult and how one might reach each goal. All of this is complicated enough with just a chunk of steel, but you add several more layers of complexity when a spring is involved. 

 

So basically, don't bother worrying about any of this just buy the gripper you want and file accordingly to get additional difficulties. You can swap a handle but it's difficult to do without altering the spring so just be aware of that. 

[Blacksmith513]

Yeah as a hobby blacksmith who’s annealed and tempered a few things in the past. I honestly wouldn’t mess with it. They are cheap enough, if you mess it up your out the gripper. I’d be worried of weakening the spring and causing potential harm to your body.

I’m sure it can be done, I’m sure I could do it and most people here. Splash water on the spring if you do do it to keep it cool.
 

if you do it, try and find the specs on the type of steel the spring is. Honestly though your time is better spent just closing the grippers.  

[Alex K]

19 minutes ago, Climber028 said:

Tempering can start as little as 300F for some steels, but a lot of epoxies will give way around 250 to 275F so if you're careful it will work. A candle might have a high enough temperature but likely lacks the required energy to accomplish this. Would be easier to just use a real torch kept at a distance to remove it. 

If you aren't already into metallurgy or black smiting, I'm going to say the average person had roughly zero chance of ever tempering something correctly, time, temperature, and type of steel are all important variables that need to be controlled. 

 

People are also always mixing up tempering and annealing, and also conflating toughness, hardness, and ductility with no idea which one of these makes a spring more or less difficult and how one might reach each goal. All of this is complicated enough with just a chunk of steel, but you add several more layers of complexity when a spring is involved. 

 

So basically, don't bother worrying about any of this just buy the gripper you want and file accordingly to get additional difficulties. You can swap a handle but it's difficult to do without altering the spring so just be aware of that. 

 

Thank you very much for the detailed answer! You're right, this has to be done with great precision.

In many years of engineering I've also learned a decent amount about metals, tempering and so on, but it's nothing compared to the knowledge of an experienced metallurgist who has actually done lots of stuff with metals  basically, theory meets real life 

[Alex K]

2 minutes ago, Blacksmith513 said:

Yeah as a hobby blacksmith who’s annealed and tempered a few things in the past. I honestly wouldn’t mess with it. They are cheap enough, if you mess it up your out the gripper. I’d be worried of weakening the spring and causing potential harm to your body.

I’m sure it can be done, I’m sure I could do it and most people here. Splash water on the spring if you do do it to keep it cool.
 

if you do it, try and find the specs on the type of steel the spring is. Honestly though your time is better spent just closing the grippers.  

Yeah, probably going slightly over 150°C (which, according to our books, would be sort of the breaking point at which the steel would begin to change properties), wouldn't weaken the spring enough to make a difference in term of safety and snapping at some point (seems like only 5-10% of tensile strength could be lost by reaching around 200°C). Going far above that probably would make it not safe to be used as a gripper spring

[Blacksmith513]

7 minutes ago, Alexander Koss said:

Thank you very much for the detailed answer! You're right, this has to be done with great precision.

In many years of engineering I've also learned a decent amount about metals, tempering and so on, but it's nothing compared to the knowledge of an experienced metallurgist who has actually done lots of stuff with metals  basically, theory meets real life 

Yeah metallurgy is very interesting. I don’t know much, but what I know fascinates me. I need to spend more time learning it, I’m more of a heat it and beat it kinda guy.  I have a hard time sitting down and reading scientific things. Good luck. I’m sure you can do it.

[acorn]

I've made quite a few springs and had to do tempering, etc. Though have not wound alot of full sized ones, most of them have been for reduced scale kids, or teen sized grippers as far as quantities done. I ended up building a small pid controlled heat treat oven to do my final stress relief and tempering after the winding process to get the accurate temp control I was looking for, for time. Without that I was seeing springs that would not hold their spread with use. Much like the HG grippers. The full sized ones I have done go up to around #3 sized springs but I hate to do them as it is such a pain to do the winding. I was never able to source proper spring wire larger than that.

If you end up getting those handles off cleanly and want the gripper converted to an adjustable mount one, let me know.

- Aaron

[Climber028]

I know an extraordinary amount of metallurgy through engineering and there's no chance I could accurately temper most metals it would take me months of work to come close, knowing how to design and spec something is totally different than actually producing it. 

 

That was a good tip about the water tho, just put the spring in water, keep the handle put and torch the handle to break the adhesive free, safe and easy. 

[Alex K]

Thank you all for the suggestions! I might just stick with the grippers for now, and not try to move the spring from one to the other! One of these is in pristine condition and is from 2012, so it's a very valuable item! Would be a shame to lose it

[Cannon]

3 hours ago, Alexander Koss said:

Do you guys think maybe some epoxy-dissolving solution could be of use? 

There’s no way for it to get down in there. 

[Cannon]

3 hours ago, Alexander Koss said:

I just tried to do so with a candle, probably not enough heat overall. I might try to boil it somehow and pull it off or twist it!

If you go the heat route, it takes a gas torch and more time than you’d think. 

[Fist of Fury]

9 minutes ago, Cannon said:

If you go the heat route, it takes a gas torch and more time than you’d think. 

Nah, works fine with a heat gun. 

I would just try with a few random grippers, then inspect them, and rate them. Before and afterwards to see if they get affected or not.

[Alex K]

As mentioned earlier, I've really been going bananas with heat mods of some of my grippers, creating both lighter and harder versions, narrower spreads and so on. I've reached 150-200°C (400F) at most I think, 150 (300) was the highest measured local spring temperature. The grippers functioned fine afterwards and didn't really lose any resistance, even after extensive use. But going through with this with rare vintage grippers is a whole different story  

[Cannon]

1 hour ago, Fist of Fury said:

Nah, works fine with a heat gun. 

I would just try with a few random grippers, then inspect them, and rate them. Before and afterwards to see if they get affected or not.

I guess what I meant was "more heat than a candle or hot water can offer."