All About Pocket Knives

Every now and then i wonder if displaying pocket knives in the "half open" does irrepairable damage to the backsprings.
I mean does the spring eventually get a "memory" that affects the snap on opening and closing.
75% of my knives are displayed in one form or another and i would hate to think i am doing them an injustice.

Any opinions or facts would be greatly appreciated.

AussieBosun wrote:Every now and then i wonder if displaying pocket knives in the "half open" does irrepairable damage to the backsprings.
I mean does the spring eventually get a "memory" that affects the snap on opening and closing.
75% of my knives are displayed in one form or another and i would hate to think i am doing them an injustice.

Any opinions or facts would be greatly appreciated.

I have seen arguments for and against this forever. I don't think anyone has been able to show any hard evidence that half open blades weaken the springs. I might worry about the material around the pin being under stress though.

If you enjoy displaying them, then you should show them. It would be a shame for them to sit in a box somewhere and not be seen. Or maybe, pick a model that you have doubles of and use those for your "open" models.

Great collection, BTW.

Glenn

I would not worry about the springs.Display them and enjoy them.I have mine on display and half opened .I will leave them to the kids and let them worry about any problems.Most springs can take a load and sit there it is the continual movement of springs that cause them to weaken .Take your pruning shears when locked closed they are under full load .

Shearer wrote:I would not worry about the springs.Display them and enjoy them.I have mine on display and half opened .I will leave them to the kids and let them worry about any problems.Most springs can take a load and sit there it is the continual movement of springs that cause them to weaken .Take your pruning shears when locked closed they are under full load .

My understanding is that Shearer is correct.

The same issue has been raised concerning firearm ammo magazines.It has been commonly held that magazines should be rotated giving the springs "a rest" so the springs do not weaken and take "a set." However a couple of years ago a metallurgist wrote a lengthy article explaining that remaining under tension does not weaken the spring. Rather it is the cycling up and down that theoretically could weaken the spring. Even then it would take a good spring thousands of cycles to weaken.

If anyone has experience with failing knife springs a description of the circumstances could be useful.

WOW, sweet collection Aussie!

Just to play it safe, I only display open blades on my knives that have half-stops. But that's just me. I have heard some say leaving tension on the spring over many years will make a blade lazy.

I have a dealer display from the late 70's with the handles of the knives faded on one side , blades are untouched however the 108OT has a lazy snap , i have oiled it but it has not improved . I'm not certain all the knives in the display are original and i realize that the 180OT is fairly common to replace but because of this one knife i had to ask the question.
Guess i will just keep an eye on them when i take em out to play .......

I have mixed feelings on the issue of displaying knives open.
I have seen some that have been displayed open for years with no noticeable negative effects to the springs. I have seen others displayed open for a short while that have weak springs.

I think the size of the springs has a lot to do with the springs becoming weak. The 108OT you mention is a pretty small knife with small springs. I have not seen a large knife like a 25OT or a 125OT that have been affected by being displayed open.

Another possible cause could be inconsistent heat treating of the springs. I have heard of bad batches of springs breaking while stored closed in the boxes. IIRC that story was from many years ago (1930s) and not from Schrade, but the point is; there can be inconsistencies in the heat treating that cause springs to weaken.

I think you are right; you will just need to watch the knives and check them from time to time to see if you notice any weakening of the springs.
I would also avoid displaying a knife open if I notice the spring is weaker than others of that pattern number.