Switch to full style
Post a reply

Should I sharpen my new knife?

Sat Mar 15, 2014 7:31 pm

I just got the Kohetsu AS 240 a few days ago and although it was extremely sharp OOTB after a 2 tomatoes, 6 onions, and one bunch of celery it was having trouble going though red pepper skin and I went back to using my MAC. The next day I decided to use my MAC honing rod on it and it brought the edge right back. However, it still seems to loose its edge quickly. My dilemma is I'm new to sharpening. I've had good success on a few german knives but I am nervous to try my hand at sharpening this knife. I was hoping the edge would hold long enough for me to get more practice sharpening other knives. Mainly I'm also wondering why it seemed to loose its edge so quickly? When I look at the edge I'm not able to see a distinct bevel. Could it be the factor angle is to steep causing the edge to roll?

Michael

Re: Should I sharpen my new knife?

Sat Mar 15, 2014 7:35 pm

Go for it dude......you can do it!!!

:)

Re: Should I sharpen my new knife?

Sat Mar 15, 2014 7:46 pm

The knife is a hard steel and the edge is much steeper than your German knife. What stones will you be using to sharpen the knife? It's likely the only thing you need to do is simply strop the knife on the stones. But if the stone is not at least a 1k you might be making the edge worse.

Believe it or not you can try stropping the knife on cardboard. Get some soda box cardobard the flat stuff any flat cardboard will do...strop away and the teeth will likely be re-aligned. I doubt you've rolled the edge severely enough to warrant a complete re-sharpening.

See videos of stropping on newspaper and cardboard. Try it and let us know how it works. Really fine cutlery will get edges back and retain them much longer. The Kohetsu is far better than mac.

Re: Should I sharpen my new knife?

Sat Mar 15, 2014 7:54 pm

I have the Imanishi 1K/6K and a 140 grit diamond stone flattening plate. Should I try newspaper/cardboard or 6K first?

Re: Should I sharpen my new knife?

Sat Mar 15, 2014 8:06 pm

I would try the 6K stropping the edge , then strop on the cardboard. If you have any leather, that works good too as a strop.
If you continue to have problems with your knife holding its edge, you might have to do a touch up sharpening starting at 1K or so go to 6K then put a micro bevel at a slightly higher angle to help with edge retention.

Re: Should I sharpen my new knife?

Sat Mar 15, 2014 8:38 pm

That sounds pretty quick to me to lose it edge. I wonder if there is still a burr from the factory sharpening and it keeps rolling over?

Re: Should I sharpen my new knife?

Sun Mar 16, 2014 2:11 am

The only way to learn is to have at it, you may even surprise yourself.

Re: Should I sharpen my new knife?

Sun Mar 16, 2014 11:17 am

I suspect your new knife came with a less than 30 degree inclusive angle. Its super sharp but doesn't hold it well otherwise I can't imagine how a couple of tomatoes and 6 onions would curl the blade considering you sound like an experienced user.

I'd say do your intervention progressively.

If you have any stropping gear give it a strop, otherwise cardboard or newspaper is fine. Find cardboard that is dense. They kind that's used to back a writing pad is good.

If it still curls or dulls then strop on the 6K, then cardboard. Try different angles.

If that still doesn't address the quick dulling put your own edge on it starting with 1K.

Re: Should I sharpen my new knife?

Sun Mar 16, 2014 5:56 pm

What is your cutting board ?

Douglas

Re: Should I sharpen my new knife?

Mon Mar 17, 2014 2:23 pm

Thanks for the advice. Its a poly cutting board. I'm going to work backwards for now. Start with stropping on cardboard and paper and see how it holds up at work today then try 6k strop. I was hoping to learn to sharpen on my MAC because now that I have the Kohetsu the MAC is going to my line knife but maybe this will be the knife I learn to sharpen on.
Post a reply