30 degree "Scary Sharp"

[Mancer]

Hi pll, I was just wondering how much of a difference is there between a 40 deg razor edge from the sharpmaker and a 30 deg "scary sharp" edge.



Any1 thats tried sharpening one of their blades to the 30 deg angle plz give me an idea of just how sharp it gets to compared to the normal 40.



Many thanx, sorry if its a stupid question (but better to be stupid for 1 question than not to ask and remain stupid for the rest of yar life huh?)



MaNcEr



It's Time To Kick @$$ 'N Chew Bubble Gum

[mundele]

I sharpened my Calypso Jr. to a 30 degree edge. It is super sharp. I wouldnt try this thin of an edge with a lower quality steel though, because the edge would be so weak that it wouldnt hold very long. It's nice to have your knife that sharp, but I think for an everyday user, the 40 degree edge might be better. (although I still sharpen mine at 30... hehe)

--Matt

[Joe Talmadge]

The difference in performance is <b>significant </b> . A totally 30-degree edge will blow away a 40-degree edge. However, as discussed above, if the blade steel isn't strong and tough, a 30-degree edge will sustain damage much easier, due to rolling, chipping, indenting.

If the steel is either not so strong or not so tough, keeping to 40 degrees isn't a bad idea. If you're going to be particularly rough on the edge, for example if you're chopping or if you're cutting into something with hard elements in it, keep to 40 degrees.

If I'm not sure, sometimes I'll take the 30-degree edge all the way down to within, say, 1/64&quot; of the very edge, then put a 40-degree edge on top of that. That gives you some increase in performance, but keeps a little more robustness at the edge. If I use the knife and the edge doesn't chip out or roll too much, I'll take it all the way back down to a 30-degree edge. If it even remotely gets damaged, I'll stick to the half-and-half approach.

Note, except on choppers, I don't use a straight 40-degree edge on any of my knives anymore. They all either have a 15/20 edge (or using this thread's terminology, 30-degrees taken most of the way to the edge, but 40-degrees on top of that), or a straight 30-degree edge. My philosophy here is that there's a certain performance standard I demand of my everyday using knives. To meet that performance standard, I demand a 15/20 edge at worst, and a straight 15 edge whenever I can get it. If a blade sustains damage at those edge angles, then the manufacturer either chose the wrong steel, or heat-treated it badly. So I get rid of that knife and choose one that will be able to meet my performance demands.


Joe

Edited by - Joe Talmadge on 5/14/2001 3:56:17 PM

[mundele]

Joe, I've heard you speak of steeling knives before. Do you know where I might get my hands on a smooth steel at a reasonable price?

--Matt

[Joe Talmadge]

Matt,

I use the Razor Edge smooth steel, and am very happy with it. It's the only steel I've handled that actually holds the angle you pick. I don't know the contact information offhand, but buy any knife magazine and there's likely to be a Razor Edge advertisement in it.

I believe there are other companies offering smooth steels as well, a search on bladeforums.com in the general forum will probably be fruitful.

Joe