Ergonomics: Your Index Finger on a Spyderco

[Bolster]

I’m curious if I’m the only person with this issue? I like a knife that snugly fits my index finger because it spreads the force of the knife over a larger area of the finger. My index, at the second joint where it contacts the knife handle, is an oval in the range of 3/4 to 7/8 inch diameter. So a knife with a 3/8-7/16 radius for the index finger feels good, and spreads force of the index finger over a relatively large area (dashed lines). If the radius is much larger, then the index contacts primarily at one point, makes a hot spot, and the index gets crowded back toward the other fingers of the hand, with a cramped-up sort of feel.



Spyderco accommodates both preferences, large and small radius. Nice. I find myself drawn exclusively to the small radius knives. Note the small-radius examples below: they fit snugly even if you don’t use the small-radius choil, but instead grip the knife further back. Especially the Manix, which is exceedingly comfortable with either forward or rearward grip. But notice how tight the finger radiuses on the Manix are, which I think is one of the reasons it’s so comfortable (for me at least).




The large radius knives I admire from a distance. I like to look at them, I realize other people love them, but I’ve stopped buying them because of index finger discomfort in use. The Harpy is the antithesis of the handle shape I look for.

I like the Mule very much but I find I need to modify its very large 3/4” radius. Who has fingers that are 1.5” in diameter? When I took the Mule down to a 7/16” radius it was much more comfortable for me to use, even in its skeletonized form.



I’d be interested to hear your thoughts on this subject.

[kobold]

Hm, I enjoy my two Chaparrals, five Natives and Manix all the time, and have only a Tasman Salt (it's a Harpy), and I keep it in the garden shed. Instinct?

[Zive]

Kinda seems like you enjoy a rear grip on a knife with a 50/50 choil? Maybe I’m missing something, though I agree that when not wearing gloves the mule handle is a bit spacious.

[TomAiello]

I just played around with some knives. and I think I'm the opposite of Bolster. Maybe I just have fat fingers, but the wider radii work better for me.

[vivi]

This isn't something I have a strong opinion on as I do little stabbing style cuts, so my index finger doesn't usually get a lot of force applied to it in that area.

[Oloung1]

Maybe I just have fat fingers, but the wider radii work better for me.

This makes sense, in Bolter's illustrations, a larger finger will have more contact area with the handle, so a wider radius would be a better fit to evenly distribute grip force.

[Bolster]

Maybe I just have delicate, lady-like fingers? Perhaps that's the issue: Large radius Spydercos, like the Delica and Endura, are made for real men; and small radius Spydercos like the Manix are made for girly-men like me...?

I do tend to choke up on knives since most of my cutting is controlled. I seldom grip a knife further back for large chopping motions. (I use a hatched or axe for that!)

Kinda seems like you enjoy a rear grip on a knife with a 50/50 choil?

It's OK, but many times I'd prefer no choil, and more edge. One reason I like the Mule so much. But I'd still want to get my index finger close to where the edge starts...safely. The Dialex Junior is a favorite (even though the blade shape is a little challenging): small radius, big guard, and virtually no ricasso:

[Zive]

Mmm, would really like to get one of those Juniors in hand one day *no paedo*

I’m curious Bolster, did you see the photo BearFacedKiller posted of the Caly next to the Police? Which choil would you prefer between the two? I’ll try to dig up the photo if you haven’t.

Edit: Adding photo in question

Dimensionally similar to the C54 with a similarly acute tip. I like it!

[VooDooChild]

I can work with just about any design that isnt outright bad.

I also might be the opposite. I like big nuetral handles with room to move around.

I will also say this. (For me) The shaman has the best choil grip ever and its huge compared to spydercos other 50/50 choils.

[Woodpuppy]

I’ve never thought about it, but I suppose now I’ll be checking. I love the Millie, but it’s choil is very small, vestigial almost. The shaman is great, and it’s a rather large choil. I never had a problem with the harpy style grip; I find I often hold my knives by the sides, is which case the shape of the grip is irrelevant. Things that make you go hmm.

[Bolster]

I also might be the opposite. I like big nuetral handles with room to move around.

This is answering my question, actually. It seems to not be a big issue with anyone but me. I suspected as much. Clearly some folks like a larger radius with room to move around and adjust the grip. I tend to like handles that "lock onto" my hand. I used to own Delicas and Lums and a Centofante and had to sell them because I could never get a comfortable grip; my fingers would keep searching for the "right" grip, and the handle seemed to push my index backward.

I also think the radius issue is MAGNIFIED for a slender, especially a skeletonized, knife (my current fixation). In its naked form I find the Mule very uncomfortable to hold...until re-radiused...then very nice.