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Sharpness Tests?

What are good tests to tell if a blade is sharp enough if i have a buzz cut? the hanging hair test doesnt really work.... any other ideas?
 
What are good tests to tell if a blade is sharp enough if i have a buzz cut? the hanging hair test doesnt really work.... any other ideas?

If your like most caucasians, you can chop your arm hairs off by just hovering the blade over them.

But, doing that dulls the blade. Why are you asking? Just shave with it, and if it shaves acceptably, your all good. If not, try different angles. If it still don't work, post whats wrong.
 
so the only thing that happens if the blade isnt sharp enough is that it will be a bad shave? no more likelihood of me chopping off my face than there usually is?
 
so the only thing that happens if the blade isnt sharp enough is that it will be a bad shave? no more likelihood of me chopping off my face than there usually is?

Well....if its really dull then it can skip and give you a tendency to cut yourself that way. But you should be fine if your careful. Try shaving arm hairs. If it takes off the arm hairs fine, no more likely to chop your face up.
 
What are good tests to tell if a blade is sharp enough if i have a buzz cut? the hanging hair test doesnt really work.... any other ideas?

I've started doing the Hanging Labrador Hair Test because I seem to have an overabundance of it. Easier than plucking one of my hairs or trying get one from my hair brush.
 
I'm hearing more about this hanging hair test. So is this where you just let a hair fall on the edge of a razor and the hair will cut in half just by gravity on the hair alone? If that is the test of a sharp razor mine would fail miserably and I have been learning with a dull razor!
 
It really is pretty difficult, especially at the start of the journey, as its probably extemely rare to experience an edge that's quite so sharp in normal; life and there's nothing to compare it to. I've had bad shaves from edges that shaved me naked on the arms without my even wanting to, forcing me to wear a long-sleeved shirt. I personally use the "does it feel like there's glue on the edge when I lightly rest my thumb against it?" test. I find its definitely shave-ready when I do this and feel fear and/or awe. I've also started to use a magnifying glass to try to see the smoothness. If it looks the same texture as the rest of the blade, I assume the edge is fine, but I may be wrong on this.
 
I have a few free moments so I will add my thoughts on sharpness testing. First, I would have to agree that the shave test is the ultimate test, but hardly convienent. I think that in general the shave test is touted for the ease of communication. Describing sharpness tests is a little like explaining the nuance of a moonshot.

First, sharpness tests are NOT binary. There is no pass or fail to a sharpness test. The razor reacts and you judge the reaction, which has nothing to do with whether you can shave with the blade.

My favorite test while honing is simply running the edge off my arm, about an inch away and judging how well the razor cuts arm hair. Its simple and evaluates the entire edge quick and easy. Its important for you to come over to my house though and use my arm hair. Your arm hair might not be exactly like my arm hair, in which case I assume you have better luck with women, but that is another issue all together.

Now, in summary of testing, the thumbnail test is really not a sharpness test, but far more conclusive as an edge smoothness test. It evaluates oversharpening or undersharpening by evaluating the feeling of the blade over the nail, which should be consistent. If the razor bites into the nail smoothly this would usually indicate that the blade is somewhat sharp as well, but of no real value unless you wanted to go around clipping fingernails with the edge. You should be very concerned if the edge produces a variety of pulling or scratchy sensations as you pull the blade. No brainer there huh? I'm going to jump out and declare this test NOT a sharpness test, although some people with experience should be able to evaluate knife level sharpness using this approach, based on the biting sensation of the nail. My nails are dead though, so I have a hard time evaluating sharpness this way. If the edge digs into the nail though, something good is starting to happen.

Next, the hanging hair test is really cool, but only checks the sharpness of the edge at one very, very small point. You do not need to use hair from your head as that usually provides no feedback at all. You also get no sense of whether the blade is smooth or not. Some people have hair so fine on their heads that passing the HHT test means the edge is too fine for their tough beards or their stropping skill. These people are few and far between. But, I would also argue that the HHT does have some value, after all if you can't cut hair with a razor you should evaluate why exactly you have a razor. I recommend finding a tough curly hair on your body and starting there. After all you want to start somewhere.

One test I really like is the thumbpad test. Took a long time to use it and understand it but it evaluates whether a razor is shave ready, NOT sharp. The razor is honed and then stropped EFFECTIVELY and if both occur the wet thumb pad (wetted for atleast 20 seconds) actually sticks to the edge instead of sliding if you GENTLY move your thumb over the blade lengthwise, yes, lengthwise. What happens is the edge digs into the skin of the first layer of your thumbpad. For you squimish types you can just bound your thumb pad on the blade and you will cut the first layer of skin with the edge. This is only visible with bright light.

This test takes lots of practice and understanding, mostly because it takes a long time to learn to strop and hone effectively enough to produce an edge this nice. Most people try this test for a while and sense that the thumb slides down the edge and since the razor shaves okay they must not get the test. The real reason is because they are not succeeding at honing and stropping together.

It takes a lot of fortitude to accept the test and discount your ability though. The test though is worth every penny of understanding you achieve with it. Being able to evaluate a truely shave ready edge is worth gold in my book. Why? I dont' know. I guess I find that lathering up and trying to shave with a razor that is not ready is time consuming to me. Or maybe it just makes me feel a little silly standing there with lather on my face with this where is a hone look in the mirror; ya know?

Okay, did I miss a test? Probably. Well these are the ones I like.
 
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I like the hanging cat-hair test. My cat has long, extremely soft fur. Takes alot for an edge to cut these hairs; a straight that passes the hht with human hair usually has problems with my cat's hair. It's for me the ultimate test, if a straight passes it, I know it will shave my beard without noticeable friction.

It's especially usefull with my Nakayama; there's no use in the hht to check progress since the straight should pass hht before I move on to the Nakayama.
 
I've started doing the Hanging Labrador Hair Test because I seem to have an overabundance of it. Easier than plucking one of my hairs or trying get one from my hair brush.

Outstanding idea! I frequently have tumbleweeds of that stuff. In fact I'm sure the dog's at home right now just laying around growing hair.
 
My favorite test while honing is simply running the edge off my arm, about an inch away and judging how well the razor cuts arm hair. Its simple and evaluates the entire edge quick and easy. Its important for you to come over to my house though and use my arm hair. Your arm hair might not be exactly like my arm hair, in which case I assume you have better luck with women, but that is another issue all together.
...
One test I really like is the thumbpad test. Took a long time to use it and understand it but it evaluates whether a razor is shave ready, NOT sharp. The razor is honed and then stropped EFFECTIVELY and if both occur the wet thumb pad (wetted for atleast 20 seconds) actually sticks to the edge instead of sliding if you GENTLY move your thumb over the blade lengthwise, yes, lengthwise. What happens is the edge digs into the skin of the first layer of your thumbpad. For you squimish types you can just bound your thumb pad on the blade and you will cut the first layer of skin with the edge. This is only visible with bright light.

I'm with Alan.

Coming off the bevel setting, the razor should shave off the hairs from the arm.
Then, one stone further, when we're refining the edge, the razor should be able to clip the hair WITHOUT touching the skin, just overing above skin level.

The wet thumb test is what I use to come off the bevel setting level. When the blade "sucks" the thumb all over the blade, you're there.
 
I have a trade program with the cats in my backyard - whisker for Whiskers so they're always happy to land me one :biggrin:

Seriously, my left hand looks like I have a receding hair line but for a single hair, I have enough chest hair for all the razors in this forum.
 
^^^what Alan posted



I hear the guys at SRP are trying out the hanging thumb test.
no, that's just Glen but apparently the test failed because his thumb had a bone in it....
He doesn't really need an opposable thumb like the rest of us - the razor I shaved with this morning proves it (he honed it after the said test).
 
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