Design details that are deal breakers

[Ez556]

The biggest deal breakers for me personally are:
1. Heavily upswept edges (Reinhold Rhino, Warrior, Subvert, Tighe Stick etc) as they don’t work well for my uses and trying to sharpen all the way to the tip gives me carpal tunnel trying to angle the knife that much to keep the edge perpendicular you the stones. I much prefer a shallower curve like on the Manix, Shaman, Perrin PPT, Endura etc, the tip is much more useful and sharpening is much easier with less wrist strain.
2. Teflon washers. On a $20 knife okay, it comes with the territory. On anything that’s made to last any amount of time, I won’t do it. Every one I’ve come across that’s been used for a while cannot be centered properly while still moving freely if the lock puts any lateral pressure on the blade.
3. Cheesy/useless/poorly thought out features. Flippers that don’t actually flip the blade open, serrations that make cutting worse, superfluous features like bottle openers, hex bit cutouts and the like that don’t work well and just make the knife worse looking/feeling etc. This really describes “gas station knives” more than anything from Spyderco, but the Tropen fits that description I think. The odd wave feature WITH a flipper WITH a functional thumb hole... it just seems like he couldn’t decide what kind of opening he wanted so it just shoved them all in there, and as a result they all look a bit awkward. Pair that with the large amount of edge in the Compression Lock cutout and it just makes for a very (personally perceived) clumsy knife that doesn’t interest me at all.

[zuludelta]

4. 50/50 Choils. I'm sure this one will be highly debated, but I've really moved away from 50/50 choils on all but small/medium sized folders where I can't get a full grip on the knife without a choil. On those knives (Native 5, Dragonfly) I don't see the 50/50 choil as a "grip option" but more as the intended grip position and I'm a lot more forgiving in those cases. On larger full size knives I just don't have a need for a 50/50 choil and I would much rather gain that bit of blade space as cutting edge, and at the same time have a grip design that puts my index finger as close to the edge as possible.

I agree, at least as far as larger folders are concerned (though not really a deal breaker for me, more like a feature that I'm largely indifferent towards in larger folding knives).

I appreciate the 50/50 choil on the Dragonfly 2 & the Native 5 (and other knives in small/midsize range such as the Chaparral, Cat, UK Pen Knife, Urban, etc.) precisely because the choil makes what is a small knife feel bigger in the hand, and thus that much more controllable & secure to grip for me. And I find that the ricasso on the Delica 4/Salt 2 functions similarly for me as well.

On larger knives, however, I think there is sufficient handle real estate to obviate the need to sacrifice cutting edge length for more grip area.

5. Thumb Ramps. This last one isn't totally a deal breaker, but my preferences have definitely moved away from thumb ramps.

For the longest time, it was the "Spydie-hump" that kept me from trying Spyderco folders. My default grip has always been with my thumb extended and flat on the spine (the so-called "Filipino grip")—it allows me to index the knife's edge & tip very precisely—and the thumb ramp can interfere with that. It was only when I found the Dragonfly (which is small enough that I can bypass the thumb ramp altogether) and the hump-less Native that I really got into Spyderco folders.

Over the years, I've learned to accomodate the thumb ramp in my preferred grip by arcing my thumb over the hump, and it's allowed me to enjoy using the Delica, the UKPK & other Spydercos with notable thumb ramps (Indeed, the Delica & UKPK have become two of my favourite Spyderco designs alongside the Native, Dragonfly, Yojimbo 2, and Introvert). There are certain models such as the Para 3, however, where the hump is just so pronounced that I can't do this without sacrificing some grip security, because it would require putting some space between the back of the handle and the thenar eminence of my palm. And to me that is a deal-breaker.

[dj moonbat]

Positive blade rake.

[Bill1170]

Nothing is an absolute deal breaker for me, except shabby quality. However, I generally avoid the following features on folding knives I buy:

Rust-prone blades
Metal handles
Ball bearing pivots
Recurved blades
Excessively thick blades
Low saber grinds
Thumb studs

I would prefer not to have finger choils but some excellent models only come with them. I just prefer to grip the handle instead of the blade in normal use.

[BornIn1500]

I absolutely LOVE a 50/50 choil. I love how it really helps ME lock in my grip and being choked up also helps with being precise with my cuts.

Like Evil D said, you can get that choked up grip with a design like the Lil Temp or Caribbean without any choil at all and without sacrificing edge length. Those are great designs and I hope there will be more like them.

[acer]

Uncomfortable handles , hot spots was too aggressive scales sticky out pointy rear handle etc yes you could man up your hands or wear gloves but if uncomfortable in hand won’t use the knife , like an ill fitting pair of shoes won’t wear . Oh how I wish I had a knife shop local so I could have saved time and money on the Try Before you buy principle . It’s all the washing up the dishes don’t you know but this is users collection different matter .In

[wrdwrght]

If a blade’s cutting edge (rather than its ricasso) can drop onto my handle-clinging index finger when I’ve released its lock and flick the blade toward closure, I will not again buy a knife like it.

I refer in particular to the Caribbean and Caly 3.5, much as I otherwise admire them. Neither’s blade drops safely onto a waiting finger like my other same-lock models, whether with or without choil.

The issue for me is not bad design but inconsistency across same-lock models, which, I suppose, is a first-world problem, but a bloody real one nonetheless.

[James Y]

Knives with serrations that are too narrow, long, and/or close together, like the Cold Steel-type serrations, or certain serration patterns that tear rather than cut.

Wire clips (for the most part).

Blades whose tips don't rest far enough into the handle when closed. Meaning that after only some sharpenings, the tip will start to stick out of the handle when closed.

Overly-rough G10.

Like others have mentioned, blades with overly-upswept tips. I don't need THAT much belly on a blade, and it puts my hand in a funny position just to get the right cutting angle for most cutting tasks.

Overly-thick saber-ground blades.

Non-stainless blades on folders. I simply prefer corrosion resistance on my pocket knives.

Jim