Why are they there?

[gajinoz]

This is a curiosity question.

I was looking over my new Sebbie in a few idle moments, (as you do), and I noticed two small, semi circular grooves right beside each other machined into the inside of the handle at the rear and under the locking part.

Why are they there? I'm assuming it's to allow the spring action of the lock. Correct, yes, no?

 

[guy g]

I believe thats what tehy are for.There was a longer explaination somewhere here.I dont remember where. Maybe we'll get lucky and someone will link to it.

 

[Ookpik]

The semicircular grooves are cut into the titanium to reduce the thickness. That makes the lock bar bend mostly in one place, acting like a hinge. It also reduces the spring rate of the lock bar. When you compress or bend a spring, the force needed increases with distance moved. The force needed increases faster (in respect to distance) with a higher spring rate. If the titanium lock bar was left full thickness, there would be too much change in pressure over the distance it has to travel. You wouldn’t be able to get the correct adjustment. It would either put too much pressure on the side of the blade when you are opening and closing the knife, or not enough pressure to lock the knife open properly. Simply put, the grooves make the lock bar more flexible.