Blade Sharpness Research Project

[LRod]

I like the Kai Captain Titan Mild Pink blades much better, but in these tests, they don't seem to be quite as good as the Schicks, but I also got a lot more good shaves out of the Captain Titan Mild Pinks, so I am not sure what is going on.

What's going on I believe is that every face/skin is different. I've mentioned it before that this testing & categorizing done by Alex is awesome scientific insight on the internal workings of a blade but won't necessarily transfer over to agreeing with your face.
Some of the top tier blades agree with me and some don't where in theory they all should work perfectly.
But not all of them do!
And on the other hand, some of the "lower tier/rougher" ones work fine for me!

 

[abies]

What's going on I believe is that every face/skin is different. I've mentioned it before that this testing & categorizing done by Alex is awesome scientific insight on the internal workings of a blade but won't necessarily transfer over to agreeing with your face.
Some of the top tier blades agree with me and some don't where in theory they all should work perfectly.
But not all of them do!
And on the other hand, some of the "lower tier/rougher" ones work fine for me!

I agree 100% but for me personally the data on the blades I'm familiar with is strongly correlated with my personal experiences. So at least for this one person this is really useful. I feel like I can look at the data and get a pretty good sense of whether I'd like a blade. It's not a guarantee but my guess is probably will decrease the number of bad experiences for me.

I kind of want to try some now just to prospectively try out personal predictions.

 

[LRod]

I agree 100% but for me personally the data on the blades I'm familiar with is strongly correlated with my personal experiences. So at least for this one person this is really useful. I feel like I can look at the data and get a pretty good sense of whether I'd like a blade. It's not a guarantee but my guess is probably will decrease the number of bad experiences for me.

I kind of want to try some now just to prospectively try out personal predictions.

The data correlates with most of mine as well. What I was pointing out is that not all are always an exact science when matching to what the expectation would be (based on the data).

 

[helicopter]

This is Sotraco's Lord Extra Super Stainless blue blade, which is made in their Alexandria, Egypt plant. It is made from thin 90 micron steel with a crudely ground and brittle edge, mild but uneven in sharpness, with poor durability, balance, and consistency. I thought the first one might have been a dud, so I looked at another, and another of these before measuring the third one for the test..

It is a coarse and crude grind with errant stria, uneven transitions, and a sloppy coating. In the second picture, taken after the test, we can see that the failure mode of the steel is lots of large chipping. Perhaps they over-hardened the steel, making it brittle. That would explain the weak edge and the high standard deviation throughout the test. Whats the razor that snaps Bic blades? Maybe someone should put some of these bad Sotraco blades in one of them.

During the test, my memory was rusty and I was thinking this was a contender for the worst Sotraco blade tested, but that doesn't seem to be the case. Interestingly, these bad Sotraco blades, despite poor alignment with subjective experiences, seem to be emerging into a cluster with similar performance. I wonder if they have some recurring problem like a badly controlled furnace causing this.

The Silver Star I tested was a 95 micron blade, but this Extra and the Orange Asco SS were both 90 microns. All three have similar performance, grinds, and failure modes. I think the latter two are probably made to the same specification, and if they are both defective, made with the same defect.

Date	15-Dec-2024			Blade Thickness, mm	0.090
Blade	Sotraco	Lord	Extra SS Blue	Egypt	16-Jan-2024
Wear on Edge	0	3	6	9	12
Edges Measured	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top	Bottom / Top
Measurement Medium	Stren 4 .21	Stren 4 .21	Stren 4 .21	Stren 4 .21	Stren 4 .21
Dulling Substrate	New	Paper	Paper	Paper	Paper
Measurements	20	20	20	20	20
Adj. Std. Dev.	16	31	38	30	28
Median F (g)	60.5	65	62.5	84	107.5
Mean F (g) Top	58	72	75	92	100
Mean F (g) Bottom	63	72	72	77	88
Mean F (g)	60	72	74	85	94
BESS Adj. Factor	1.39	1.39	1.39	1.39	1.39
Avg. Adj. F (g) Top	80	100	104	128	139
Avg. Adj. F (g) Bottom	87	100	100	107	122
Median Adj. F (g)	84	90	87	117	150
Mean Adj. F (g)	84	100	102	118	130

It is inexpensive, with a street price of around $8/100, but I don't think I would want to pay a third of that for this blade. Maybe there are some better batches out there, but at $8/100, you can just get Procter and Gamble blades that are way more likely to perform properly.

Blade Sharpness Test Index

 

[pjgh]

Woo! He's back! Nice one ... while I'm okay with the Lord Extra, it's a two shave blade for me.

 

[helicopter]

Woo! He's back! Nice one ... while I'm okay with the Lord Extra, it's a two shave blade for me.

Sharp enough to get the job done at first, and mild enough that the rough grind isn't a big problem. Makes sense. I am guessing it gives some feedback and isn't good as a one pass blade. Maybe I will try it at some point.

 

[pjgh]

I got a couple of tucks of each of the Lords from RBC maybe three years back? I might have just landed on a better production run but I certainly think my ASCO and Silver Star are much sharper than the ones you have @helicopter ... but I do agree that it is very likely that these stainless blades are of a similar/same specification. It's the Shark brand (and the far-eastern market Cool) that are the sharp grind ... if that's a thing.