Lockup: 560 Vs. 551

[Talley1013]

Hey guys. I did a search before posting but didn't find anything that addressed my question specifically so here it goes. I have noticed a difference between the lockup on my 551 and 560 and was wondering if its normal. I picked up a 560 yesterday to compliment the 551 that I have had since they first started becoming available. My new 561 seems to be perfect, lockup is rock solid @ 50% and the action is as smooth as glass. When comparing the 560 to the 551 I noticed that while both knives lockup @ approx. the same place there is a marked difference. On the 551 the entire height of the lock bar touches the blade tang while on the 561 only the very corner of the lock bar touches the tang. I wouldn't think anything about but I seem to remember that being the gripe about the old strider lockup. Only having the corner of the lock bar touching the tang puts a lot of force/wear on a small area and causes the lock bar to wear quickly. When you look at the 2 locks side by side the 551 just looks more solid. My question is are other 560's like this or is mine an oddball? Did ZT move to a different lockup for a reason when designing the 56x series? I'm just curious. I plan on using the he!! out of the knife and if something goes wrong I have total confidence in ZT's warranty.

On a side note, the 560 is everything I expected it to be and more. I knew it would be smooth but I wasn't expecting it to be as smooth as it is. The knife fits my hand perfect and rides surprisingly well in the pocket for a knife of its size. I think ZT hit it out of the park with this one.

Thanks in advance for the input and have a good weekend.

 

[kreole]

The gripe with the old Strider lockup was that the tang of the blade was curved too much, not that it only locked up at the corner.

Here's a good thread on how it should contact when looking from the side (short answer is hitting the top part is the goal, which both accomplish). Specifically read Marthinus' longer post #15 http://www.bladeforums.com/forums/showthread.php/966235-frame-lock-should-the-lock-bar

 

[Talley1013]

Thanks for the link Kreole. The 560 is rock solid and I'm sure it will stay that way for as long as I own the knife. I was just wondering if ZT consciously changed the lock design from the 55x to the 56x or if the difference is a result of manufacturing tolerance. I have only looked closely at 1 55x and 1 56x so my sample size isn't large enough for me to say one way or another.