Is my knife really sharp?

[del2les]

I have been knife sharpening with my Spyderco Sharpmaker again. I can get my knives pretty sharp, but I'm somewhat unclear if they are sharp coming off the sharpener.

So, the first thing I did was grab the marksalot and my optivisor that has like 20x magnification on the top end. this helps me see that the whole blade edge is being dressed and that the burrs/damage are invisible to 20x, but how do I know if it is really sharp?

How do you do it? I've tried paper and can tell cutting vs ripping, but it seems like I should be able to see this better.

While I don't use any of the newer fancy sharpeners, I still use old school techniques and tools from the 60's. I test the sharpness by shaving the hairs from my arm with ease.

 

[oldfortyfiveauto]

Edge-On-Up Professional Edge Tester

A Standard Test for Sharpness How sharp is the edge? That is both the most important question a sharpener can ask, and possibly the hardest to answer. There are tests like cutting paper or shaving hair that are often used to demonstrate sharpness, and they are helpful to a point, but they lack...

www.sharpeningsupplies.com

 

[Dirtrax]

Edge-On-Up Professional Edge Tester

A Standard Test for Sharpness How sharp is the edge? That is both the most important question a sharpener can ask, and possibly the hardest to answer. There are tests like cutting paper or shaving hair that are often used to demonstrate sharpness, and they are helpful to a point, but they lack...

www.sharpeningsupplies.com

Very cool tool!

 

[30378wbymag]

I use a Wicked Edge sharpener for sharpening, and .3 micron diamond paste strops for finishing. I also test on whittling a human hair, this is one of my moustache hairs (don't like harvesting from up top anymore) NOT shaving but whittling:

This particular knife is one of my Shun Fuji kitchen knives in SG2 PM steel at about 62-64 HRC. Pretty incredible how sharp you can get fine grain good steel!!!

 

[Mrvmax]

I worked with a guy who bought a new knife at the gun show and brought it to work. He was showing how sharp it was by shaving the hair off his arm. It took the hair off and cut right into his flesh. Still don't know how he managed to do that.

So, be careful when shaving off hair....

 

[Taylorbok]

I worked with a guy who bought a new knife at the gun show and brought it to work. He was showing how sharp it was by shaving the hair off his arm. It took the hair off and cut right into his flesh. Still don't know how he managed to do that.

So, be careful when shaving off hair....

Don't do drugs.

 

[Bucklowery]

I have 2 secret things that will make knives like razors but I need someone who has access to old school high voltage lights

Yes the ceramic insert if these bulbs work great. They are in the 100w high pressure sodium too

Thanks

Buck

 

[victor3ranger]

Yes the ceramic insert if these bulbs work great. They are in the 100w high pressure sodium too

Thanks

Buck

I haven't found any in a long time.
I would really like to get a couple of the long ones that are 10"-12" long.

 

[Bucklowery]

I don't see those much any more but the smaller ones they do. I will have to ask the guys if they see any

Thanks

Buck

 

[victor3ranger]

I don't see those much any more but the smaller ones they do. I will have to ask the guys if they see any

Thanks

Buck

Thanks you.
The last two I had got broken, one fell off the shelf during a earthquake and the other one my granddaughter knocked off the table.

 

[Small Lady]

I use the stupid test. Inevitably shortly after sharpening a knife I will cut myself. If the cut is so clean that it only shows itself by weeping small blood droplets and burning like sin it is sharp. If the cut is gaping and bleeds profusely the blade needs a couple more passes on the stone.

You to...hi buddy.

 

[victor3ranger]

You to...hi buddy.

A few years ago I was caping a buck around the base of the antler and it slipped and hit my left thumb and split from the tip of my thumb on the right side of my nail and stopped at the joint.
That thing opened up like a split open grape.
Didn't really hurt until I got to the hospital and they started jamming needles in it so they could sow it all back together
The year before my cousin cut his thumb off at the joint and I had to take him to the same hospital to have his sown back on

 

[Bob Wright]

A few years ago I was caping a buck around the base of the antler and it slipped and hit my left thumb and split from the tip of my thumb on the right side of my nail and stopped at the joint.
That thing opened up like a split open grape.
Didn't really hurt until I got to the hospital and they started jamming needles in it so they could sow it all back together
The year before my cousin cut his thumb off at the joint and I had to take him to the same hospital to have his sown back on

That is really sharp. One has to keep your body parts out of the firing line though. Dull knives are a serious problem.