Love my new Delica K390, but need sharpening advice.

[Hjalmar]

I really like my new knife. However, it's my only fancy steel knife and when I googled about sharpening it, I got cold feet and almost wished I bought the vg 10 version. For my Bucks,Cases and Puukkos I use a dc4 Fällkniven and sometimes a Sharpmaker, finishing with a classic paste strop.

Do I need diamond rods or CBN or something like that? Which one, in this case? Anything else?

Regards Erik

Ps what angle on the Sharpmaker?

[horzuff]

You already have diamond on the DC4. Go with that, finish on a strop and You're golden. Angle is whatever You like, it can handle angles like 15dps with absolute ease

[Hjalmar]

You already have diamond on the DC4. Go with that, finish on a strop and You're golden. Angle is whatever You like, it can handle angles like 15dps with absolute ease

Oh, thanks for the advice.
Can I use regular stropping paste?

[vivi]

the base sharpmaker works fine for keeping k390 sharp.

if you end up wanting to reprofile the edge angle, I would suggest a diamond bench stone.

I would go with 15 degrees if it hits the apex on your folder. color the edge in with sharpie, do some strokes with the brown rods, then visually inspect the edge. if the sharpie is removed from the very edge / apex, sharpen it that way. if the sharpie is removed from the shoulder of the bevel behind the apex, repeat this step with the 20 degree slots.

if the sharpie still isn't being removed from the apex with the 20 degree slots, you should reprofile the knife.

https://www.harborfreight.com/4-sided-d ... 92867.html - this $12 stone can handle reprofiling k390 easily. it's also great for applying toothy edges that can last 6-12 months without needing to be re-sharpened.

[8th_Note]

These diamond 4-sided blocks are $12 at Harbor Freight. I use it to sharpen all of my knives including M4, S90V, K390, HAP40, etc. This is all you need to keep any knife razor sharp. It has 4 different diamond grits (200, 300, 400, and 600). I also have a leather strop loaded with 1 micron diamond paste (the strop was $18 on amazon, the paste was $12). You don't have to spend much money to maintain your knives.

[sal]

Hi Hjalmar,

Welcome to our forum.

sal

[RustyIron]

when I googled about sharpening it, I got cold feet and almost wished I bought the vg 10 version.

Do I need diamond rods or CBN or something like that? Which one, in this case? Anything else?

Hey, Erik.
Google gives you a wide cross section of opinions from everyone, and the result is that you'll come away with an average level of knowledge. That's great for those who aspire to mediocrity. Luckily, you've come to the right place, where the opinions can be from folks who actually know a thing or two about knives and the cool flavors of steel that Spyderco provides.

Personally, I think you made the right choice in getting the K390 rather than the VG10. For me, it keeps an edge better, and is easier to get a spectacular edge really quickly. The problem with K390 is that it likes to rust. If you live in a humid environment, keep it clean and oiled. You WILL get a patina on it.

As for sharpening, the Sharpmaker is good. You can get a great edge with the standard rods. Diamond or CBN rods give you a little different edge, and will remove material more quickly. If you want to remove a lot of material when you've decided to change the angle or repair some damage, the Sharpmaker can be slow.

My preferred setup when repairing an edge, thinning it, or just taking it to the Nth level, is an EdgePro Professional. Most of the time I use diamond matrix stones, and sometimes some electroplated diamond stones. I like the very precise look that I can achieve with this. The price tag isn't for the faint of heart, but EdgePro makes some equally capable models that won't set you back as much.

Rob

[Hjalmar]

Thanks
I think I will begin with the Sharpmaker s standard rods. Do you think the white rods work for polishing, even though it's a hard steel?

[vivi]

Thanks
I think I will begin with the Sharpmaker s standard rods. Do you think the white rods work for polishing, even though it's a hard steel?

it will take some time but it will work.

an efficient approach would be to utilize a microbevel. polishing the apex would not be time consuming with a standard sharpmaker, but polishing the entire bevel may be.

if you're not sure what a microbevel is, it's the process of sharpening the very apex at a slightly more obtuse angle than the rest of the edge bevel.

in fact I believe the sharpmaker was originally intended to be used this way. sharpen the knife at 15 degrees for the edge bevel, then use 20 degrees to hit the apex. gives a combination of good cutting performance and a strong apex, while making touch-ups less time consuming than sharpening the entire bevel.

[RustyIron]

Thanks
I think I will begin with the Sharpmaker s standard rods. Do you think the white rods work for polishing, even though it's a hard steel?

If you're mindful of maintaining your angle, you'll be removing so little material that you can try it out for yourself. Sharpen with the brown rods, use the knife, decide for yourself. Next time, finish with the white rods, use the knife, decide for yourself.

For me, I usually sharpen between 250 grit and 1000 grit. That gives me good edge that cuts nicely. Sometimes I'll go sub-micron, but it's more for fun and looks rather than any practical cutting performance.

These are things you just need to try. It's like going to Baskin-Robbins. You'll never know that you prefer Quarterback Crunch until you order a scoop.

[navin johnson]

K390 in my experience is easier to sharpen than VG-10. It may take a little bit longer, but the result is notably better

I never go finer than a 300 grit edge on any of my knives

While a course edge may not trim your fingernail as well. It will last much longer. I would avoid stropping unless you really know what you’re doing as you will weaken the edge.

A 100 grit and 300 grit diamond bench stone does everything I need. If you want to go a bit more refined to use the brown rods and then done.

I put K390 away, wet and dirty sometimes there is a patina, but no rust (I live in Seattle and I sweat a lot). The only way I could give it to rust, was to wipe sweat on the blade after a workout, close it, and put it inside the waistband of my sweaty undergarments and leave it there for a while and yes, there was a few specs of rust

[Hjalmar]

Hi Hjalmar,

Welcome to our forum.

sal

Thank you very much indeed. Nice to be here.

Erik Pålsson

[Hjalmar]

Now I have looked around and figured out that I will get the CBN rod for my Sharpmaker and 5 micron paste for my strop. I got really interested in an article in Science of Sharp, a bit hard to understand though. Thanks y'all for all the great input.

Erik Pålsson