R.I.L. "Framelock" Question

[Bolster]

To get the framelock to bend into position behind the blade, some metal is removed at the base of the lock. On a lot of knives, the metal is removed from the outside, and the metal bends to the inside. On other knives the metal is removed from the inside, and the metal bends...to the inside. How does this work? The frame's lock can bend either toward or away from the removed metal...? How is the direction of the bend controlled? Does the cutout not control the direction of the bend? Is the bend induced by deforming the metal rather than removing the material in the relief cut? Maybe that's the source of my confusion.

[CasperFatone]

The material is removed to make the area that is bent thinner for flexibility, and it shouldn’t significantly matter which side of the lock bar it is removed from. I’d think there is be a slight advantage to removing it from the outside of the knife because this puts the “pivot” point of the bend more in line with the tang of the blade, which might very slightly reduce unwanted flexing of the lock bar when it is in the locked position.

If that doesn’t make sense try to imagine an extreme hypothetical scenario where the scale on the lock side is extra wide, say 1” thick. Removing material from the inside would put the bar at a sharp angle when locked, and if there was pressure coming from the tang it would want to bend the bar sideways. In contrast, with that same ridiculously thick scale if all material is removed from the outside that bend point of the bar is in the same place it would be on a normal knife. However, on a knife using 1/8” thick scales I don’t think this whole situation matters too much.

[SpyderNut]

Good question. The reason the metal is removed from that area on a frame-lock is because the lock bar needs to bend in order to engage the tang of the blade and it would otherwise be too difficult to bend if left at full thickness. A number of custom makers seem to prefer having the cutout on the outside of the scale because it is said to be stronger/less prone to lock failure than having the cutout on the inside.
On the frame-locks that I’ve made, I decided to go with the cutout on the inside primarily for aesthetics and also to eliminate hot spots from the cutout area.

[Bolster]

Thanks for the explanation. Yes, makes sense, and the logic of it is coming back to me now. So the direction of the bend isn't controlled by where the metal is removed, the metal is just "bent" into position after being appropriately thinned. Got it.

[Brock O Lee]

Good question @Bolster. I've always prefered the RIL cut-out on the inside for aesthetics (Sage 2, Military), and was puzzled about why so many designers would choose to put it on the outside. I never thought to ask the question!

[Ramonade]

The reason might just be a question of time invested for the piece on the machine. Maybe if the cut is made on the same side as another cut it makes the process faster (and cheaper).

[Brock O Lee]

Looking at the Sebenza's and Inkozi's, it is interesting that Chris Reeve, the inventor of the integral lock, put the cut-out on the inside.

Edit: Umnumzaan too

[p_atrick]

I've seen YouTube videos where somebody tries to explain why one way is better than the other. This came across as "bro science" to me. They didn't cite or show any experiments with an attempt at controlling the variables. They just spoke in hypotheticals. I prefer the looks of the lock bar cutout on the Sage 2 over the Chef.

[Mushroom]

I wouldve guessed it’s just a matter of aesthetics. There may be some physical advantage to the cutout being on the inside or outside but I’m not going to pretend I’m the one the knows what that advantage may be.

[ChrisinHove]

If the hinge metal is on the outside edge of the scale, then it will need to flex more acutely for the lock bar to function.

Might that matter?

[JacksonKnives]

I've seen YouTube videos where somebody tries to explain why one way is better than the other. This came across as "bro science" to me. They didn't cite or show any experiments with an attempt at controlling the variables. They just spoke in hypotheticals. I prefer the looks of the lock bar cutout on the Sage 2 over the Chef.

To be fair, we're already speaking in generalities here. A test/experiment with one model of knife may not be at all applicable to other models.

[p_atrick]

I've seen YouTube videos where somebody tries to explain why one way is better than the other. This came across as "bro science" to me. They didn't cite or show any experiments with an attempt at controlling the variables. They just spoke in hypotheticals. I prefer the looks of the lock bar cutout on the Sage 2 over the Chef.

To be fair, we're already speaking in generalities here. A test/experiment with one model of knife may not be at all applicable to other models.

Fair enough. I've yet to see anyone credible make a claim one way or another. If anybody has, do share.