Sharpening Stainless Steel

[Don Penniman]

From the recent pocket knives thread I noticed that many of us carry Swiss Army Knives. I use it for something several times a day, and my family expects me to have it available at any time (except for that awkward moment in the airport). The stainless steel blades are certainly practical for outdoor work or recreation, but I have never been able to get a good edge using oilstones. I have since read that the best way to sharpen stainless steel is to use very fine to ultrafine wet or dry sandpaper.

I have been using an Accusharp sharpener:
497226
It gets a pretty good edge, but I would like to get a little better. Before I start experimenting, any suggestions as to what grit to start with and what grit to finish with? At what point does an ultrafine grit reach a point of diminishing returns? I have sandpaper ranging from 600 grit to 5-micron and lots of dead-flat surfaces so experimenting is just a matter of time.

I have noticed that stainless steel has just about completely taken over the market for outdoor knives. Even the venerable Buck Folding Hunter now has a stainless steel blade.

[Cameron Wood]

IME, sharpening SS blades is no different from carbon steel ones. I've carried a swiss army knife daily for over 50 years, & not had trouble sharpening.

I regrind the small blade as a scalpel- narrow point, ultra-sharp, for splinter removal and minor surgery.

That carbide sharpener shown will make a crudely sharp edge, but tends to make the line of the cutting edge uneven.

There are multiple ways to sharpen, and multiple claims of "best".


Sandpaper needs to be glued down to work well for blade sharpening, IMO.

[Edward Weber]

SAK blades are "tough" but not that hard. They put up with daily use and abuse and because they're relatively soft, they can be sharpened easily.
Other Stainless steels, like the 440 varients found in many outdoor knives are harder, and as a result, they take a good keen edge but it's a bit more difficult to get them there, Field sharpening is not as easy.
There is a balance to achieve between edge retention, hardness, sharpening and corrosion resistance. Every maker has their own view of what steel is best for their knives.

[Derek Cohen]

I freehand sharpen all the knives in our house, along with any pocket knives I own (there are a couple of Swiss Army amongst them), and use a single 600 grit diamond lapidary disk for this. These are, compact, flat and the diamonds are nicely uniform. The disks are available on eBay for about $10. The end result is very acceptable.

Regards from Perth
Derek

[Ben Ellenberger]

I’ve had the same experience as Ed. The blade on my Swiss Army knife is easy to sharpen, but the steel isn’t very hard. So, I don’t try to sharpen it to a shallow bevel and I don’t expect it to hold a very sharp edge. It is plenty sharp for general use, but it isn’t as sharp as my chisels and planes.

I just use regular oil stones or diamond stones. I’m pretty sure I don’t bother polishing with my finest stone.

[steven c newman]

"Field" sharpening is usually done with a Steel..
Mine is a Schrade Old-Timer Honesteel

[Luke Dupont]

I use oilstones on all of my stainless steel knives, including SAKs which I use a lot.

I'm able to get great edges, albiet not quite as good and not as long lasting as on carbon and tool steels like O1 or Japanese steels.

I go camping / bushcrafting quite a bit and usually carry a very small arkansas stone. I find Arks actually work better on knives than they do tools, even.

[David Carroll]

I switched over to diamond stones a few years back, so that's what I use now. They do a great job. I do keep a strop handy and use it pretty regularly. I'm not sure it gets as sharp as a Mora knife, but it gets sharp enough. Considering that it's used for everything from open packages and cutting cardboard to slicing pepperoni at lunch, edge holding is more important to me than taking a surgically sharp edge that blunts the first time you cut into store brand sausage... ;-)

DC

[Jim Koepke]

My kitchen knives are all stainless these days. They have been sharpened on water stones, oilstones, abrasive sheets and diamond stones. Most recently they have their blades refreshed on oilstones in the shop when needed.

In a drawer in the kitchen is an extra fine diamond stone mounted on a piece of wood:

497460

That is used to tune up an edge on knives between trips to the shop.

My SAKs are now mostly sharpened on oilstones.

These two small stones are great for sharpening in the field:

497459

On the right is one that cuts like a Washita. It wasn't yet wiped off from its last use. The black one on the left is a finishing stone. Both of these have leather pouches for protection and storage. A little plastic bottle of mineral oil goes a long way when out and about.

jtk

[Alan Rutherford]

I freehand-sharpen my pocket knife, all the kitchen knives and everything else and have progressed from files through cheap Harbor Freight diamond stones through wet-or-dry sandpaper on glass to 1000 and 4000 grit stones and lately an 8000 grit Shapton, but the best tool I have for sharpening my blades is a strong (10x+) magnifier. Everything works better when you can see what you're actually doing.

[steven c newman]

In use this evening..
497566
Logo on the sheath?
497567

SCHRADE
OLD-TIMER
HONESTEEL

Pocket Knife?
13058-A
STAINLESS
PACKISTAN

Brass, Walnut and Steel....bare spot on the forearm says it is sharp...3 minutes total to hone the edge..from start to putting things back..

[Robert Hazelwood]

The softer variety of stainless in these knives can form a tenacious burr that is difficult to remove on oilstones, and that is probably whats keeping them from really feeling sharp. Once you have raised a burr from each side, you have to really focus on light alternating strokes into the stone to work the burr off. Raising the angle a hair at the end will also help.

Sandpaper might be more forgiving about the burr. For a pocket knife I'd never bother with more than two grits and not with anything finer than 2000 grit. And probably would be happy with 600 grit. You can use a block of wood or leather strop loaded with compound to add some polish. But for most jobs I'd use a pocket knife for a little tooth on the edge is nice.

[Don Penniman]

Thanks gentlemen for the insights. I think i will give it another try on my Arkansas stones (need to make new holders for them anyways). I also have Kershaw and Buck knives with stainless blades that need attention.