Yojimbo 2 defect

[Evil D]

It seems to me the issue is more because of the smaller lock cutout than the lock itself. This is why it's less of an issue on the Para 2.

[ulyan]

smaller lock cutout than the lock itself

Yes, that is what I showed on these photos :D

[Michael Janich]

Also one question to Michael Janich:
I've seen drafts of Yojimbo's prototypes with a Ball Bearing Lock. Did you consider it when designing Yojimbo2? I think this lock is enough strong and making this knife truly ambidextrous.

Dear Ulyan:

The Photoshopped images of a Yojimbo with a ball bearning lock were done by a forumite--they did not come from Spyderco's engineers. The challenge we faced with choosing a lock for the Yo2 was the width of the blade and finding a place to fit it in the closed position. After much experimentation, the Compression Lock was the clear winner because it offers the most usable space within the handle of the knife when the blade is closed. That's why it was the only lock that cound be practically used on the Junior.

Now that I have a few Yo2's to play with (for a long time, even I only had one), I'll take one apart and experiment with lowering the lock tab to see if I can eliminate the pinching issue from a design standpoint. If I'm successful and it doesn't compromise the user's ability to release the lock easily, I'll make a formal recommendation to amend the design. That's how the C.Q.I. process works.

Thank you all for your feedback and enthusiasm for the Yo2 design.

Stay safe,

Mike

[ulyan]

Now that I have a few Yo2's to play with (for a long time, even I only had one), I'll take one apart and experiment with lowering the lock tab to see if I can eliminate the pinching issue from a design standpoint. If I'm successful and it doesn't compromise the user's ability to release the lock easily, I'll make a formal recommendation to amend the design. That's how the C.Q.I. process works.

Thanks, Michael!

You are very helpful to take part in these discussions as the author of this knife. In our discussions on Russian forums we noticed a few things:
1) We really need a folding trainer version!
2) One of the best features for self-defence knives are the Emerson Wave, now we must to use third-party solutions.
3) I'm have Spyderco PPT, it's also a good knife with a similar concept (but I doubt that it is so effective). This knife have some features that may be useful to Yo2. It is thicker and corrugated handle (for easy holding of the knife) and low-rider clip (making this knife more concellable)
4) One man was interested about the serrated version. Will it be effective?

[ulyan]

Also if it possible - can the moderators rename thic thread to Yojimbo 2 - trouble with opening?.

[Matt David]

Has anyone modified their Yo Jimbo 2 to try and get rid of this pinch point? I’m considering doing it to mine because I’m having the same issues. Honestly, I don’t ever carry it for this very reason. I’m just not willing to have a knife in my rotation that I need to open in a particular way to avoid getting ‘bit’ (just my personal preference). If anyone has done this, I would really like to know what you did exactly and what the results were. Thanks in advance!

[SubMicron]

When I get lazy with my index finger on various compression locks, because I have loose skin there, I feel the pinch.

This happens exclusively when I play and fidget. In use, I don't recall ever noticing it.

I own many brands of knives in a range of price points. The majority of knives or knife platforms, require some adjustment with usage. Many of them punish your hands in much more severe ways.

I'm currently recovering from a ridiculously inconvenient strain in my index finger from a frame lock flipper of a different brand.

Specialty knives, designed to excel at a certain usage style or task, require different techniques for usage.

Like riding a bicycle, the end user does share some responsibility for proper usage. That does include me gripping a frame lock flipper in a way where my fingers dont ride the lock bar.

Meanwhile over time, in that pinch spot, your skin will thicken and the effect will lessen.

[Red]

For what its worth, I recently received my Yojimbo 2 and absolutely love it. No “pinching” whatsoever. It just feels flawless. Now I need to wait on the trainer and do some work with it but I just love it!

[Evil D]

Wow it's really bazaar reading my old posts in this thread, because this really isn't much of an issue these days. Maybe I need to go back and carry a Yojimbo 2 for a while, because my Caribbeans have never punched me.

[SubMicron]

I need to start looking at the date of the original post before I take the time to write a reply.

[Michael Janich]

Dear Ulyan:

I believe the drafts you are referring to were artist's conceptions on the forum. In other words, they were computer drawings of an idea, not mechanical drawings of a knife that actually folds. The challenge with the Ball Bearing lock is that it takes up space in the handle that the blade can't fold into. That's why knives like the Manix 2 must have an index-finger choil, to create space for the blade to fold "around" the lock.

My ultimate expression of the Yo 2 design would have a Bolt Action Lock, which I believe is one of the most underrated locks ever. Done properly, it requires less space in the spine of the knife than Ball Bearing or Axis Locks, yet offers the same operational mechanics.

For the record, I also considered the Ball Bearing Lock when designing the YoJumbo, but decided against it for the same reasons.

Stay safe,

Mike

P.S. This is an old thread and, I must admit, I'm not fond of the thread title. With regard to that "issue," in addition to modifying your opening technique slightly, it is also possible to file down the top of the Compression Lock release tab to mitigate the problem. Of course, the question then becomes, "Why don't you just do that in production?" The answer is that we would then have another forum thread titled "My Yojimbo 2 is too difficult to close." Perfection--especially in knife designs--is ever elusive...

[James Y]

I always enjoy and learn a lot from Mr. Janich’s posts.

Jim