Help me understand Fine Edges, different steels and different results

[Gunsnknives]

Good day all,

First of all, my knives are generally for light use only. More than anything else, I sharpen my knives and play with them for my own learnings.

I have 4 steels I generally play with: CPM3V, M390, 154CM and S90V.

I sharpen on a Lansky at 17 degrees (each side) all they way to the super fine, blue stone (finer than the white 1000 grit stone) and finish on a loaded strop, then a bare strop.

My experience is:

• Fresh off stones and stropped in all steels will slice toilet paper
• "Tree Topping" sharpness is relatively easy to achieve with 3V, then next is 154 CM then M390 and hardest is S90V
• I can maintain the "Tree Topping" sharpness of the 3V with a loaded strop only...the other 3 steels need to be put to the stone
• My 3V will lose the "TP slicing" sharpness after use and stropping...but will regain the "tree topping" sharpness

I'm not sure if I have a specific question, but I'm wondering if I should be able to maintain all my steels on a strop (only light use after all) and still be able to keep both "TP slicing" sharpness and "Tree Topping" sharpness.

Or am I doing something incorrect in my sharpening.

Thanks to all here on the forums. You have taught me how to make my knives sharper than I ever thought possible...now I'm becoming a little on the obsessive side :thumbup:.

 

[db]

Yes all should be able to be touched up on a strop. However, if you wait too long you will have to go back to the hones. If you really want to get obsessive go even thinner with your edges. A trick to do this with the Lansky is ajust the gide rod on the hones to get even a shallower angle. If I remember correctly pushing the gide rod in all the way increases the angle and to lower the angle you attach the rod at the very end. Could be the other way around but is easy to check.

 

[Obsessed with Edges]

Take a look at the 'Steel FAQ' sticky (from upper portion of the Maint forum page), linked here:

http://www.bladeforums.com/forums/showthread.php/368828-Steel-FAQ

Different steels will definitely behave differently, especially with regard to taking/holding extremely fine edges. To a large degree, the carbides in the steel affect that a lot. Some carbides are much LARGER, so it's much more difficult to take steels with them to a very fine edge. Carbides also affect how easily (or not) a steel can be sharpened/abraded/filed away. LOTS of other variables, though. Which is why I recommend the above reading material HIGHLY.

 

[Gunsnknives]

Good read, thanks David and db.

I just might try a shallower angle on the Lansky if I get a Spyderco Delica or Stretch in ZDP 189. From all my poking around the forums, it seems that the steels like to get the sharpest (or are easy to sharpen) are (in no particular order):

-ZDP189
-M4
-Hitachi Super Blue
-M390
-VG10/N690

These forums are costing me $$$ with all the testing and playing with steels

 

[HeavyHanded]

All steels should be capable of being touched up on a strop, though in my experience the edge apex will slowly become more obtuse as you go until it looses a lot of cutting efficiency. At this point they'll have to go back to the stone. Also, IME getting an edge to cut TP requires less refinement than tree-topping hair. Finishing at different grit values and stropping with comparably sized abrasives will produce some very different cutting effects - something else to take a look at while you learn.

This machete was done by hand on an 800 grit silicon carbide sanding belt and stropped with white compound from Sears. After a camping trip it may or may not be capable of repeating this feat with just some stropping, but I've had no trouble getting it back to crosscutting newspaper by just using a strop or two. Following some hard use I'll strop on a coarse grit (220 silicon carbide) with the rough side of a leather strop and follow it with something finer (white Aluminum oxide, green CrO or even 1200 grit SiC) and this keeps it sharp longer than stropping with just a fine abrasive without needing a trip back to the stones.

 

[Ben Dover]

You have been seduced by the Dark Side my good man. Sharpening knives is an addiction! And an expensive one indeed!

 

[Noctis3880]

If you're only using your knives for light use, I would recommend 13C26 or perhaps find someone to custom make a knife in AEB-L steel at high hardness for you.

 

[me2]

Increase the edge angle on your knives with the M390, S90V, and 154CM. They should be able to be touched up on a strop unless there is some sort of fracturing going on at a microscopic level. Then a strop wouldn't help much, unless it was like HH's rough strops.

 

[Ben Dover]

Increase the edge angle on your knives with the M390, S90V, and 154CM. They should be able to be touched up on a strop unless there is some sort of fracturing going on at a microscopic level. Then a strop wouldn't help much, unless it was like HH's rough strops.

15 degrees per side (30 inclusive) is a near ideal angle for these steels. It allows one to lightly "touch up" the blades with strops, Crock Sticks, or the Sharpmaker.

 

[Gunsnknives]

Thanks for the input folks.

I'm actually quite happy (but of course, not completely satisfied) that I could get a nearly HHT (Hanging Hair Test) edge off my 154 CM with some patience and football to watch.

If I'm looking at doing "Stupid Pet Tricks" with my edges, what are the best steels to get super fine edges?

I'm tempted by ZDP189 and Aogami Super Blue...but now there's AEB-L and 13C26 to think about.

And yes...this is going to cost me some money as now I'm looking at a Delica and Caly in the above mentioned steels...nevermind the folding prybars and Tacticool knives I already have!

 

[Ben Dover]

I'm tempted by ZDP189 and Aogami Super Blue...but now there's AEB-L and 13C26 to think about.

... !

ZDP 189 is an excellent steel. M390, CPM S90V, CPM M-4, Elmax, and CTS20CP are also superb. Do a a bit of research on the steel manufacturers' websites and you'll find more information than you want.

Crucible's website is excellent, although pure agony to navigate. Bohler-Uddeholm, USA has a very informative website as well, as does Carpenter Steel.

Another resource is to research the steels the "high end" custon makers like Phil Wilson and Farid, and semi-custom makers like Bob Dozier, and Rick Hinderer are using. :thumbup: