Thread: Thumb test...

I just touch the blade with the thumb and maybe gently run it along the edge a bit. If it sticks, the blade is getting there, if it doesn't, then you need more work on the hone. You can also feel roughness of the edge that way.

First, no. In my opinion conducting a thumb nail test after an 8K is fine. I would actually suggest that it would be prefered.

Second, here is the only rule. Do not do the thumbnail test after stropping. You'll blow the edge.

Third, the thumbnail test is done to assess the edge quality, both sharpness and overhoned. If the razor does not dig at all into the nail it is dull. If it bounces, jumps, makes weird noises or pulls during the stroke (in stops and starts) it is overhoned. If it pulls smoothly and digs into the nail it is sharp and smooth, both really important qualities (smoothness of the edge is a very overlooked criteria in honing).

You can do this test before or after any hone, the grit doesn't matter but your testing general sharpness so you could do it any any point. Since testing after stropping will damage the edge you can imagine someone not doing this test after the 8K since the true test of sharpness will be the thumbpad test. So if thats what you read I won't dispute it. You could use the thumbnail test simply to check for egde quality and not worry about digging at all.

Next, on to the thumbpad test. I pivot the spine in such a way that the edge swipes the thumb and its print. Like I'm strumming the blade for some music. Its that simple. During the swipe you'll get the most feel at about 30 degrees, like your shaving your thumb print. What I feel with a truely sharp razor is the edge catching on the lands of my thumb print and biting into the skin. I can feel the razor as it touches the tops/lands and goes into the grooves of the print. This "catching" feels like a drag or a really finite edge moving over the print of the thumb. You could conversly just swipe your thumb over the egde. I get the most feel of the edge at 30 degrees. Remember the thumb has to have soaked for a while. Atleast thats the classic version of the test.

So the rolling motion that your confused about is me rolling the edge over my thumb print.

So, here is the way I do it (absent a good microscope). Hone on 4K then check that the edge is not overhoned and digs a little via the thumbnail test. Then hone on 8K and do another thumb nail test, expecting at this point that the edge should bite into my nail and remain smooth. Then a few more passes on 8K. Then strop and use my thumbpad to test the edge for sharpness. Failing that I go back to the 8K and return to the strop a few times. Then shave. The razor should draw on my strop and provide a good, if not perfect, shave. I may return again to 8k as the shave test is more reliable to me than even the thumbpad test. The big benefit is I never shave test with a razor that will cause irritation, something that bugs me to no end.

Thanks Alan,

I think I got it now. I haven't gotten a "Sticky" feeling yet, but I can feel a bit of difference in the blades edge between laps. Thanks again.

Your welcome, sorry if I confused you . . . unfortunately this is a process better done by reverse engineering. Hone until you have a perfect razor, then conduct every sharpness test on the planet to get a feel for what your looking for when honing. Another reason to get an edge honed by someone else I guess.

I have a razor out right now. Unfortunatly, I dont use mail to often and I think I sent it out a very slow way... I was expecting like 7-8 bucks, and it was only like 3 or 4 lol... Oh well... until it gets back, I have my shavette and this Ebay razor to play with.

I agree with the testing process that AFDavis uses with one exception. I only use the thumbnail test after the 4000 grit and never when using the 8000. When I am on the 8000 then I only use the thumb pad test and the Hanging Hair Test to indicate if the razor is ready for a shave test.

My reasoning? I feel that the thumbnail test dulls a 8000 edge and is not necessary. The 30x microscope tells me if the razor is overhoned. The thumbnail test is used to determine if the edge has developed an even bevel ( which is the function of the 4000 hone)and to feel if all the nicks are removed. A well developed bevel will lightly draw into the nail evenly for the entire length of the edge. If the nicks are removed then there will be no grabbing or hestitation in the draw. You stay on the 4000 hone until these criteria are met.

Hope this helps,

Good advice Randy, the edge should be sharp enough to move off the nail test before 8K (I don't hone with either 4 or 8 K myself very often, thus didn't like that "rule").

I did some research on the thumb test this weekend and noticed something I forgot to mention that I thought was interesting. If the thumb nail test gives two results, then you have a flaw in your honing technique. For example, if it digs in one part of the blade and is smooth at another you need to go back and review your technique.

awsome, thanks for the advice and the help guys.

Originally Posted by AFDavis11

Your welcome, sorry if I confused you . . . unfortunately this is a process better done by reverse engineering. Hone until you have a perfect razor, then conduct every sharpness test on the planet to get a feel for what your looking for when honing. Another reason to get an edge honed by someone else I guess.

This is very true. My honing took a huge leap forward when I got a blade honed by Joe Chandler and spent a while finding tests that his would pass and mine wouldn't. Armed with that knowledge I was able to quickly adjust my honing technique to pass those tests, and eventually got to the point where I could read the feel of the blade on the hone well enough that i don't really use the hair-popping test much at all anymore (the shapton 15k and translucent arkansas hones are particularly communicative during honing).

Originally Posted by mparker762

This is very true. My honing took a huge leap forward when I got a blade honed by Joe Chandler and spent a while finding tests that his would pass and mine wouldn't. Armed with that knowledge I was able to quickly adjust my honing technique to pass those tests, and eventually got to the point where I could read the feel of the blade on the hone well enough that i don't really use the hair-popping test much at all anymore (the shapton 15k and translucent arkansas hones are particularly communicative during honing).

What do you mean by 'particularly communicative'?

I have yet to even hone with my norton 4k/8k or strop, and am all ready interested in a finer stone than 8k. I'm in this for the long haul. I intend to get a 15k-ish stone, and 0.25-1 micron diamond pastes. Whether I put these diamond pastes on a paddled strop or hang strop I've yet to decide. I know starting with a paddled strop is recommended, but I'm not in a hurry and have the luxury of approaching things gingerly and in thought out ways.

I must admit I'm getting flustered about how information on straight razors is reaching me. It's like taking a corrispondance course on how to put a round peg in a round hole. There is a small protrusion in the peg and a small crack on the inside of the whole. The next logical thing to do is write a letter to an authority asking if it's fine to procede. Or should I just use my savy wit and line up the protrusion with the crack and 'go for it'. This is how silly my ignorance has been making me.


I'm finding out a great deal of the history certain stones, then stop and wonder, "If I make a pasted hanging strop, do I put paste on both the linen side, and the hyde side?" <---btw, anyone can feel free to answer that