Question for Bill, Inconsistent Lock-up on Vintage US Switchblades

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novice
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Question for Bill, Inconsistent Lock-up on Vintage US Switchblades

Post by novice »

Bill:

I've only noticed this on some vintage US switchblades. Press the button to open but sometimes they don't lock up and the blade bounces back. Timing it so that you release the button as the blade hits the max opening point seems to minimize this. But sometimes they don't do it at all and latch up correctly. I have a few knives that do this, all US, and one is in "like new" condition. In each case the blade is solidly locked when open. I can't figure out if it is pilot error, sear wear, or a design difference? I've never noticed this on an Italian style stiletto for example. Can you shed any light on this?

:?:

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Bill DeShivs
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Re: Question for Bill, Inconsistent Lock-up on Vintage US Switchblades

Post by Bill DeShivs »

I'll swear I answered this post already. Hmm.
Ok- these knives were adjusted at the pivot area to have resistance at the near-open position. Sort of like brakes to slow the blade right before lock up. It's usually a fairly simple process for me to repair it without disassembling the knife. Note- Peening the pivot rivets will not help, and you could break your handles. The rivets just go through the pivot-which is separately peened steel tubing. (A bushing, actually.)
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Re: Question for Bill, Inconsistent Lock-up on Vintage US Switchblades

Post by novice »

novice wrote:
novice wrote:
Bill DeShivs wrote:I'll swear I answered this post already. Hmm.
Ok- these knives were adjusted at the pivot area to have resistance at the near-open position. Sort of like brakes to slow the blade right before lock up. It's usually a fairly simple process for me to repair it without disassembling the knife. Note- Peening the pivot rivets will not help, and you could break your handles. The rivets just go through the pivot-which is separately peened steel tubing. (A bushing, actually.)
Thanks for the answer Bill. I could not find anything on this when I searched but I did not look all that intently. This makes complete sense now that I understand how they operate. I did find that one of the offenders had some linty greasy muck buried in the latch/groove on the blade. Cleaning all of that out dramatically improved the lock-up.
Last edited by novice on Thu Sep 03, 2015 10:01 pm, edited 1 time in total.
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