I have read a number of threads in the past few months that the Apparition 670 with the Optimizer was problematic.

Was this an issue when it was first released? Or was it a problem throughout?
What was the problem?
Did this problem include the 672?

The Optimizer was a great idea.

Feed a hardened torsion bar through a small hole at the base of the knife with an angled tip which (hopefully) matched the tang of the blade. All that held the bar in place was a very small set screw, which often allowed (due to the length of the bar) slight movement either to the left or right of where the tip hit the tang.

The idea was to have the bar apply tension to the back of the tang, so when the blade was opened the applied force launched the blade from about 30 degrees to fully open.

I'd say there were two problems with this: One, to open the blade often required a lot of force to overcome the angle of where the torsion bar hit the tang. Two, that force was applied to the same pointed thumbstud now used in the 890 Torrent, but in this case really caused pain for many of us, and you did have to get the angle on the stud just right.

In the end what was brilliant about the design was: With the ability to loosen up that little set screw you were able to remove the torsion bar - and turn the thing into a manual opener. And in manual you had a very decent knife and no more problems with the pointed stud to open it.

While the problem was the same in both 670 and 672 models, I thought the 672 was superior in it was slimmer (and lighter) with much better G-10 handle scales.

The 672 I owned was a nice knife with a great D2 Wharncliff blade and still worth seeking out...but I'd remove the torsion bar and just drop it in the blue box.

OK so no problems with the knife other than design. No lock up problems? The liner lock worked fine. The detent held the blade in the closed position with the torsion bar removed etc. It just ended up being that massive torsion bar.
I wonder why BKC used a pointed stud? They knew it required a larger stud to swing that blade out and had to know it may bother a few.

I made a trade for a NIB 672 plain edge. I love the Warncliffe blade. I assume the removal of the torsion bar is a simple process if I need to do it.

Thanks Joe for you detailed answer!!

You're welcome Doc. Just don't lose that little Torx wrench for the set screw. And a tip: If you remove the torsion bar turn the set screw down a few times so it stays put in case you ever decide to reverse the process.

Easy on the screw,it is easy to cross thread......

Good advice Gents. It's a super tiny screw.

I once removed a set screw like this on the trigger assembly of a rifle and the 26 pieces (all tiny) exploded out of the VERY complex maze of parts, springs, leaf springs, more springs (smaller than the size of your pinky finger nail) etc. The instructions never said anything about that. It was my customization project. It cost $125 for a new trigger assembly.

You tips will not be forgotten, for sure.

The 670 was one of the most bizarre Benchmades every sold...

The AO was an issue.

The liner is paper thin.

It was heavy as a brick, and that fake Kudo Horn handle...

The sum of the parts just did not add up to an equation that worked for me...

The thumb stud has to go.

Anyone know what size I'm looking for?

The knife kits supply places sell universal studs but you need exact sizing. I no longer have a caliper to measure it.

The challenge is how to grab the pointy stud so you can loosen it. I used a pair of needlenose on mine and scratched it a bit. Didn't help that BM used Loc-Tite on the screw threads.

Again without the torsion bar installed it's much less of an issue.

Joe,
I removed the Torsion Bar and it felt like an average knife. In other words, just a plain old folder. Not Benchmade like. Maybe you know what I mean. I can’t explain it. With the torsion bar it has a cool gitty up and go. I like it and feel that if the stud was more comfortable it may work for me. I figured removing the stud was a no brainier with the screw on the left side but have not tried it yet. I’m sure I can do it. If I can’t find a replacement I’ll remove the torsion bar.

Man, I love that blade. I’m a big fan of the Warncliffe and find this one particularly useful. Benchmade should do more of them.

You removed the stud on your 672, why?

BTW: That was my post #666

This message has been edited. Last edited by: Dr Forthington Pringles,