Blade Sharpness Research Project

[slimshavy]

Finally, I have had some time to measure another blade. This is the Personna Platinum Chrome Super Stainless Blue-Red blade. It was produced in Israel for the UK market on May 15, 2019. It was generously provided for testing by @WVShaver, who took some photos of the package. It comes in a plastic tuck with ten blades, single wrapped plain waxed paper.

View attachment 1897572

It has a date code, which I like to see.

View attachment 1897573

It has mirrored printing so the individual halves are printed the same. For symmetrical blades like this, I have been putting a "T" for "Top" on the edge that is on top when I open the wrapper the normal way. I decided to mark it before taking the photo so I wouldn't get mixed up.

View attachment 1897575

It has a 3-stage grind. The entire bevel is 0.37mm. The primary bevel has an uneven medium grind. The portion with a secondary grind, including the honing at the edge is 0.13mm. The secondary bevel had a fine uneven grind. The honed portion of the edge is 0.03mm and has a fine polish. The entire bevel has a fairly thick coating. The blade is 0.100mm thick. I got a micrometer.

The Israeli Personna Platinum Chrome Super Stainless blade produced on February 3, 2013 for American Safety Razor Company, which is Ever-Ready, has a thicker coating and a shorter secondary bevel than this blade; the primary grind looks similar to it.

View attachment 1897576

After testing, the coating is gone, the bevels have smoothed, and the chipping at the edge is extremely fine. This steel is very tough, resilient, and durable.
View attachment 1897577

Information Summary:

There are some changes to the format here. @BigAlVista has generously offered his help in re-formatting my existing data to be more useful for analysis, by putting everything into a single table. He has spent a lot of time on it, and it will enable much more sophisticated analysis of things like consistency of sharpness across the length of an edge, or between edges of various blades. He is an expert in data science, and I wouldn't have thought to do things how I am doing them now without his recommendations and help. I changed the formatting a bit so this summary report can be produced automatically. This is the first blade for which I have used the table to collect the raw data.

Date	20-08-2024
Blade	Personna Platinum Chrome UK Red-Blue - 12/1899 - (Israel)

Shaves	0	3	6	9	12	Avg 0-6
Location	Bottom	Bottom	Bottom	Bottom	Bottom
Medium	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22
Dulling Substrate	New	Paper	Paper	Paper	Paper
Measurements	24	24	24	24	24
Adj. Std. Dev.	5	12	11	17	10
Median F (g)	53.5	50	49	49.5	56
Mean F (g) Top	51	47	47	53	62
Mean F (g) Btm	56	57	55	56	54
Mean F (g)	54	52	51	54	58
BESS Adj. Factor	1.22	1.22	1.22	1.22	1.22
Av. Adj. F (g) Top	63	57	57	65	75
Av. Adj. F (g) Btm	69	69	67	68	66
Median adj. F (g)	65	60	60	60	68
Mean adj. F (g)	66	63	62	66	70	64

Here you can see it with all of the Personnas I have measured.

View attachment 1897592

In overall sharpness it is most similar to the Red Israeli Ever-Ready Personna, but this blade is sharper and more durable. It also has a different grind and coating. I suspect the steel is similar, the improvement is sharpness comes from the thinner edge, and the improvement in durability is a combination of a better coating, this blade is 6 years newer, and the sharper starting point; just my best guesses; I am not confident in that hypothesis.

View attachment 1897593

Blade Sharpness Test Index

I have enjoyed these posts from the beginning, despite not quite understanding what the numbers mean. I've sort of pieced it together from your words. This table seems simpler, which is good for non-engineers like me, but I still struggle to read it. Could you, or @BigAlVista , or someone who gets this explain some of it?

Specifically, I understand the rows titled Shaves, Medium, Dulling Substrate and Measurements. For the rest of the rows, I believe the F refers to the force, in grams, required to cut through the medium. I get the Median and Mean F, and I think I get the standard deviation as well (although I'm not sure what the distinction is with the adjusted standard deviation).

What I don't get:
Bottom and Top: This is in Location (only Bottom, apparently) and throughout the measurements (top and bottom).
BESS: Who is she and why is she important?
All the "Adjusted" Fs: Why are they adjusted? Should we pay more attention to these adjusted numbers than the median and mean F numbers in the rows above?

Thanks for doing these!

 

[cranewarrior]

BESS: Who is she and why is she important?

How does the Edge-On-Up BESS sharpness test work?

How does the Edge-On-Up BESS sharpness test work? ➤ Knivesandtools blog with tips and tricks ✔ Top lists of the best products ✔ 'How to' guides ✔ Versus articles

www.knivesandtools.com

It's essentially an objective means of measuring sharpness in knives and other sharp edges. The now-vanished refinedshave site used it:

I haven't read helicopter's methodology thoroughly, but I imagine he is using a similar tool.

 

[cranewarrior]

How does the Edge-On-Up BESS sharpness test work?

How does the Edge-On-Up BESS sharpness test work? ➤ Knivesandtools blog with tips and tricks ✔ Top lists of the best products ✔ 'How to' guides ✔ Versus articles

www.knivesandtools.com

It's essentially an objective means of measuring sharpness in knives and other sharp edges. The now-vanished refinedshave site used it:

I haven't read helicopter's methodology thoroughly, but I imagine he is using a similar tool.

And he's already doing so much hard work, but it would be fun to see a short video of a partial test.

 

[helicopter]

I have enjoyed these posts from the beginning, despite not quite understanding what the numbers mean. I've sort of pieced it together from your words. This table seems simpler, which is good for non-engineers like me, but I still struggle to read it. Could you, or @BigAlVista , or someone who gets this explain some of it?

Specifically, I understand the rows titled Shaves, Medium, Dulling Substrate and Measurements. For the rest of the rows, I believe the F refers to the force, in grams, required to cut through the medium. I get the Median and Mean F, and I think I get the standard deviation as well (although I'm not sure what the distinction is with the adjusted standard deviation).

What I don't get:
Bottom and Top: This is in Location (only Bottom, apparently) and throughout the measurements (top and bottom).
BESS: Who is she and why is she important?
All the "Adjusted" Fs: Why are they adjusted? Should we pay more attention to these adjusted numbers than the median and mean F numbers in the rows above?

Thanks for doing these!

Top and Bottom:
Oops. I need to fix that. I am measuring both edges, Location line needs to indicate that. In the other lines, "Top" and "Btm" are right, and tell you which edge so you can see if there is a variance.

I am using the same test fixture as in the video, and I have some of the BESS media (white container), but it is way too expensive for regular use and is not as consistent as the fishing line I am using (blue container) for pennies a test. There is a difference in cutting force, so I came up with an adjustment that should be >99% accurate. The process is detailed earlier in the thread, but I just did 150 cuts with BESS media and my fishing line, and calculated a proportion factor.

F is actual peak force measured in grams. BESS adjusted force is the calculated force, comparable to a test done with BESS certified test media.

With the previous test, I started using the adjusted force for the standard deviation because that provides better comparability.

 

[helicopter]

I took, a look at these Chinese Shanghai Gillette Flying Eagle Stainless blades. These certainly appear to be genuine with some anti-counterfeiting measures including an outer sleeve and holographic sticker. The sleeve tells how counterfeit blades are inferior, and how Super Blue Gillette Swordfish, Flying Eagle and Rhino blades all have these counterfeiting measures. I wonder what the other blades mentioned are. I understand that the Swiss Rhinoceros is a Matgicol blade, but perhaps Shanghai Gillette has a similar brand, or sold a brand to them.

The two edges are ground differently. This is the bottom edge. I think it is not produced to the specification, because the transition from primary to secondary bevel is wavy.

The top edge is a lot different. The bevel is 0.37mm tall. The Primary grind is coarse and the scratches vary in size. The secondary bevel to the edge is 0.16mm, with a medium grind and scratches that vary in size. The last 0.02mm is honed smooth. The medium coating covers the entire edge evenly.

The bottom edge has some small chipping and some medium denting after the test. There were only a couple spots like this, but I wanted to show it. You can see how the dent is correlated to the wave in the secondary grind. There weren't any dead spots, so the dented parts must have remained reasonably sharp, despite the deformation. I don't think I would want to be shaving with something like this, though.

The top edge looks as it should after the test. There is some small chipping, and the coating is worn, which are both normal for properly produced razors.

Information Summary:

There isn't actually much variance between the edges. It is quite dull for a stainless blade, but otherwise, performance is surprisingly good.

Date	21-08-2024
Blade	Flying Eagle Stainless	Shanghai Gillette	China	Yellow-Pink	04-18-2014

Wear on Edge	0	3	6	9	12
Edges Measured	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top
Measurement Medium	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22
Dulling Substrate	New	Paper	Paper	Paper	Paper
Measurements	20	20	20	20	20
Adj. Std. Dev.	10	8	8	11	8
Median F (g)	75	82	83	86	84
Mean F (g) Top	79	81	86	90	82
Mean F (g) Bottom	75	82	81	79	87
Mean F (g)	77	81	83	85	85
BESS Adj. Factor	1.22	1.22	1.22	1.22	1.22
Avg. Adj. F (g) Top	97	99	104	110	100
Avg. Adj. F (g) Bottom	92	100	99	96	106
Median Adj. F (g)	92	100	101	105	103
Mean Adj. F (g)	94	99	102	103	103

When I ordered these on Ali-Express, I probably should have just spent a third as much to get one tuck of five blades.

Blade Sharpness Test Index

 

[helicopter]

2.0 due to 10 picture limit per post.

I actually noticed that wavy bottom edge before taking any photos, but some blades just have that and do alright. I took about 5 measurements with the first blade, noticed it was quite dull, and took a closer look. The top edge isn't wavy, but the bottom is. I decided to throw that blade out and re-start the measurement procedure with a fresh blade.

In this picture, you can see the waviness on the bottom edge of the first one, which is in the shavette.

And here, with the light at another angle, you can see the waviness of the second one, not it the shavette. Measurements are all of the one that is on top in these photos.

The waves can be seen partially at this magnification. The height of the secondary bevel is inconsistent, and too short.

 

[helicopter]

@PALORAZOR sent me another Dorco STP301 blade. This is a known new production Vietnamese blade, and as he expected, it is a lot sharper than the other STP301 I measured. Overall, this one is quite sharp, quite durable, and quite consistent. If you can find one like this, it is a great value.

It has an even and fairly thick coating, and a 2-stage grind. The Primary bevel is an uneven medium grit and the edge is honed to a polish. The entire bevel is 0.29mm tall, and the honed portion at the edge is 0.04mm. It appears to be ground to the same specification as the other Dorco Prime Platinum STP301. The coating on this one is a lot thicker, which explains the J-shaped sharpness curve for this one compared to the straight sloping curve of the other one.

After the test, most of the coating remains, except at the secondary bevel, which is smoothed out. We see some fine chipping along the edge typical of good razor steels.

Information Summary:

Date	21-08-2024
Blade	Dorco	Prime Platinum	Vietnam	STP301 Blue	01-01-2023

Wear on Edge	0	3	6	9	12
Edges Measured	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top
Measurement Medium	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22
Dulling Substrate	New	Paper	Paper	Paper	Paper
Measurements	20	20	20	20	20
Adj. Std. Dev.	7	5	6	13	13
Median F (g)	50.5	48	49.5	50.5	56.5
Mean F (g) Top	46	45	47	51	60
Mean F (g) Bottom	54	49	53	52	57
Mean F (g)	50	47	50	51	58
BESS Adj. Factor	1.22	1.22	1.22	1.22	1.22
Avg. Adj. F (g) Top	56	55	57	62	73
Avg. Adj. F (g) Bottom	66	60	65	63	70
Median Adj. F (g)	62	58	60	62	69
Mean Adj. F (g)	61	57	61	63	71

This new one, notated with "vn" as a known Vietnamese sample, is significantly sharper than the other STP301 I measured.

Blade Sharpness Test Index

 

[helicopter]

I forgot to mention, the Flying Eagle Stainless is 0.113mm thick, and the Dorco STP301 vn is 0.094mm thick. That partially explains the shorter bevel and sharper edge on the Dorco.

 

[Jay21]

I forgot to mention, the Flying Eagle Stainless is 0.113mm thick, and the Dorco STP301 vn is 0.094mm thick. That partially explains the shorter bevel and sharper edge on the Dorco.

I always felt the Dorcos were thinner than other blades. This confirms it.

 

[PALORAZOR]

GREAT info on the Dorco blade. Glad to know your testing jibes with what I experienced shaving with it. Thank you so much for doing that @helicopter !!

 

[helicopter]

I measured the WMARK R-1 Super Sharp Swedish Stainless blade. This blade had one edge that was very sharp and one with a wire edge that failed prematurely. It is a private label blade and I am not sure who makes it, but it is Chinese.

The bottome edge, which is my standard for photography, has a wire edge. It is double beveled with a thick sloppy coating. The primary bevel has a coarse and uneven grind, and the secondary bevel is honed, but the scratches from the primary grind approach the apex. The entire bevel is 0.35mm tall, and the secondary bevel is 0.07mm. The blade is 0.095mm thick.

After testing, the defective bottom edge has some very large chipping.

I took an additional photo of the top edge after testing because of the large variance in cutting force observed and the difference in the wire edge. The coating is gone on the secondary bevel, and there is some small chipping along the edge typical of good razor steel. I think this blade might be produced by Carlife-Razor China, like the Pearlmax because they have a similar grind. It is hard to make a comparison of the performance because the grinding process clearly is out of control.

It is another blade of good steel, with an inconsistent grind. You certainly should avoid this batch, but it is possible you will get lucky and find a decent one. It isn't a good bet considering this isn't even a cheap blade. You will be much better off with FlyDear or Dorco if you want to take a gamble.

Information Summary:

Date	21-08-2024
Blade	WMARK	Model R-1	Swedish Stainless	China	01-01-2023
Wear on Edge	0	3	6	9	12
Edges Measured	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top
Measurement Medium	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22
Dulling Substrate	New	Paper	Paper	Paper	Paper
Measurements	20	20	20	20	20
Adj. Std. Dev.	8	13	23	26	33
Median F (g)	50	48	53.5	60	64.5
Mean F (g) Top	47	45	47	52	55
Mean F (g) Bottom	57	61	69	84	92
Mean F (g)	52	53	58	68	74
BESS Adj. Factor	1.22	1.22	1.22	1.22	1.22
Avg. Adj. F (g) Top	57	54	57	63	67
Avg. Adj. F (g) Bottom	69	75	84	102	112
Median Adj. F (g)	61	59	65	73	79
Mean Adj. F (g)	63	65	71	82	90

The chart fails to convey how bad the wire edge side is, because each bar is an average of the two edges. It is another low-quality overpriced private label blade with cool graphics and a nice box. So far it seems like it would be best to avoid all of the private label blades, regardless of whether they are made in China or the EU.

Usually, if you are making great blades, you will know it, be proud of it, and be happy to say exactly where the blade was made, when it was made, and who made it.

Private label blades are not all terrible, but many of them are, and I haven't seen one that is a good value. I am still going to keep testing them, though. They are an important component of the market, regardless of my disappointing experience with them so far.

Blade Sharpness Test Index

 

[Sweeney_]

Nice results on the Dorco.
I look forward to the Accuforge testing.

 

[lasta]

Sorry to be the bearer of bad news, but you've got yourself some fake Flying Eagles.

I wouldn't trust AliExpress for Gillette products.

 

[helicopter]

Sorry to be the bearer of bad news, but you've got yourself some fake Flying Eagles.

I wouldn't trust AliExpress for Gillette products.

I dont doubt it, but how do you identify them as counterfeits?

Where would you get genuine ones if not Ali Express?

 

[Barberbite]

I measured the Assured For Men (AFM) blade from Dollar Tree today. I put some comments about the blade in the current Dollar Tree AFM razor thread.

Are these the same blades made in Vietnam in the factories where Dorco blades are made and used?

 

[helicopter]

Are these the same blades made in Vietnam in the factories where Dorco blades are made and used?

I don't think so, these are the cheapest generic Chinese blades, and they are terrible. They aren't even made from proper blade steel. These are blades that are so bad, if they were the only thing available, I am not sure if anyone would shave at all. The Dorcos that didn't perform well were all still usable.

 

[lasta]

I dont doubt it, but how do you identify them as counterfeits?

Where would you get genuine ones if not Ali Express?

Well, no date code, flimsy guide strips.

Bevel also looks wider than anything Gillette, and AFAIK, all Gillette blades are above average in the polishing department.

In any case, I live in China and there are more fakes floating around than what Gillette produces. Even the real ones are middle of the road at best. I wouldn't bother.

 

[Barberbite]

Bevel also looks wider than anything Gillette, and AFAIK, all Gillette blades are above average in the polishing department.

In any case, I live in China and there are more fakes floating around than what Gillette produces. Even the real ones are middle of the road at best. I wouldn't bother.

Which counterfeit blades are most commonly found around?

I guess in this case you are referring only to Gillette counterfeit blades.

 

[lasta]

Which counterfeit blades are most commonly found around?

I guess in this case you are referring only to Gillette counterfeit blades.

Gillette (Super Blue especially), Bic and Dorco mostly.

 

[helicopter]

I measured the AccuForge SS Coated blade by AccuTec, which is made in their Verona, Virginia plant. The vendor, Razor Emporium, calls it "Microcoated" and says it is the same blade as the Personna Lab Blue, with new branding. Not unimportantly, the packaging is also different. It comes single wrapped in heavy printed paper, with 250 blades packed tightly into a nice cardboard box and no tucks. The box indicates they hace a coating and fingerprint oil.

My box had some shipping damage, because Razor Emporium shipped it to me, along with several other blades, in a padded bubble envelope with no additional packing material. I got them on sale at 15% off. The damage doesn't ruin the blade performance, but these are not as sharp as the Lab Blues I got from Sally's in a blade bank with five blades in it. The box is heavy, the blades are fragile, and these boxes of blades normally cost $90 before tax; Razor Emporium's decision to ship them from Arizona to Michigan in an envelope is unacceptable. If you are going to buy some, make sure you include something in a glass bottle or jar in your order so they are forced to pack them properly in a box. Incidentally, I ordered a Rex stand and Razor on scratch and dent from them a while back, and the massive 12.2 ounce stand and the razor arrived in zip-locks bouncing around in a small box with some broken air bags, both definitely "dented" as promised.

The ones from Sally's have a date code laser etched on them, which is really cool, but this one has no printing or etching, like the cheapest generic blades. It is a minimalist approach, but I prefer to see a date code somewhere. This is a new product, so we can guess its age, but the lack of a date code will probably cause some confusion eventually.

Coating and Grind
Coating Thickness	Light
Coating Evenness	Even
Bevel Coating Coverage	100%
Entire Bevel to Edge, mm	0.420
Primary Bevel Scratch Size	0.012
Primary Bevel Scratch Consistency	Uneven
Primary Bevel Proximal Transition	Even
Blade Thickness, mm	0.104
Secondary Bevel Transition to Edge, mm	0.135
Secondary Bevel Scratch Size	0.005
Secondary Bevel Scratch Consistency	Uneven
Secondary Bevel Transition Line	Even
Tertiary Bevel Transition to Edge, mm	0.030
Tertiary Bevel Scratch Size	Polished
Tertiary Bevel Scratch Consistency	Even
Tertiary Bevel Scratch Transition Line	Even

The coating and grind look the same as my Personna Lab Blue from Sally's. The specifications for the steel, grind, and coating have no significant differences.

After the test, the coating is worn, the tertiary bevel is smoothed out, and there is some tiny shipping at the edge. The steel, grind, and coating are all excellent.

I shaved with one twice and tested it. I didn't get good shaves. I had a lot of irritation. I thing that can be attributed to my technique, since i have had great shaves with the Lab Blue from Sally's.

I also corked one and tested it. Corking provided a small increase in sharpness on both edges.

The blade is very sharp and consistent and exceptionally durable.

Date	22-08-2024
Blade	AccuForge	AccuTec	SS Coated AGBL	USA	01-01-2024
Wear on Edge	0	3	6	9	12	2	1
Edges Measured	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top
Measurement Medium	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22	Stren 6 .22
Dulling Substrate	New	Paper	Paper	Paper	Paper	Face	Cork
Measurements	20	20	21	20	20	20	20
Adj. Std. Dev.	5	5	7	9	11	7	6
Median F (g)	48.5	47	44	45	50	44	46.5
Mean F (g) Top	47	47	46	49	52	43	43
Mean F (g) Bottom	50	46	45	42	49	44	49
Mean F (g)	49	46	46	45	50	43	46
BESS Adj. Factor	1.22	1.22	1.22	1.22	1.22	1.22	1.22
Avg. Adj. F (g) Top	58	57	57	59	63	52	52
Avg. Adj. F (g) Bottom	61	56	54	51	60	53	59
Median Adj. F (g)	59	57	54	55	61	54	57
Mean Adj. F (g)	60	57	56	55	62	53	56

The wear curve resembles the other one.

I can't recommend this blade from Razor Emporium when the same blade seems to be available at lower prices with better manufacturer packaging and better retailer handling at much lower prices. I don't know if the packaging and handling caused the difference in sharpness, or if it is batch variation, but there is no reason to spend more on this one. Get the US-made Lab Blues in 5 packs, or 100/120 packs for half the price from someone who handles them with proper care.

Blade Sharpness Test Index