He said in the original post that he’s used and likes both, he just has to choose one. Obviously he’s the only one who can do that, I guess he just wanted to watch people talk about them.
Nacet verses Perma Sharp Blades
- Thread starter bbobbdd
- Start date
@helicopter testing confirmed that the Nacet is indeed objectively sharper
If I had to pick one, I would go with Perma-Sharp.
Only 600 Perma-Sharps? Do you have kids? Grand Kids? They'll have nothing to fight over but a few tucks of Silver Stars, Gillette Super Thins and a lonesome tuck of Tigers!
Free McRib Sandwich and Large Kool-aid for you sir!
Also have 99 Nacets, 199 Gillette Platinums, and 200 Vintage Scottish Perma Sharps on the way , ill get an update picture once the vintage blades arrive, i reckon ill stop at 2500 blades once i get there, that should see me through to my box, then my kids get the rest. Forgot 100 Tiger Platinums.
I don't know after how many years, but the blades get old.
This is what the old London Bridge looks like after one shave, which wasn't pleasant.
This is what the old London Bridge looks like after one shave, which wasn't pleasant.
I reckon you could shave a tribe of Wookies with that lot, you actually have more blades than my local shaving shop has for sale.
He confirmed that his sample blade was sharper than another sample blade. The blades would need to be sampled more times and across different production dates to be able to verify your statement with statistical confidence. You also must assume that the testing apparatus and methods are sufficiently accurate and can provide repeatable results without adding variation of their own.
It is useful data, and @helicopter has shed a lot of great light on the whole subject, but it is not definitive knowledge at this point.
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In any razor I own, I cannot go a perma-sharp without getting nicks.
Between them, Nacets work great in my more aggressives whereas Minoras work best in my least.
Between them, Nacets work great in my more aggressives whereas Minoras work best in my least.
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Sure, the individual blades tested might not be good representations of the specification. And of course someone else may have gotten one that isn't a good representation.
I have tested a lot of PPI blades, and they are not like Sotraco and Czech blades. There are enough samples to show that.
The testing apparatus is an electronic scale with a peak force gauge. That's pretty mature technology. The measurements are basically all accurate. The exceptions are if I bump it with my hand and don't notice or something. I take 100 measurements of every DE blade, so it isn't something that is going to change the overall results.
The reason you see statistical variation in the data sets is that the edges aren't equally sharp in every spot. It has nothing to do with inaccuracy. If I measure the same spot over and over, the result does not vary more than 3% or so.
I think people reading the thread often misinterpret variation in the edge at different locations for inaccuracy in the measurements.
Because the fixture has a known mass, the scale gets verified on nearly every cut.
The dulling procedure, cutting strips of paper on a rubner cutting board, could be more consistent than it is with some specialized fixtures, but repeat blade tests show it is repeatable. I have demonstrated that it is much more repeatable than shaving my face with a safety razor.
The photographs taken under a microscope with a calibrated distance grid and image scaling in GIMP is also mature technology. Again, there just isn't going to be any significant variation.
I don't need a huge sample of blades to draw a good conclusion here. I could grab one more Perma-Sharp, and one more Nacet from different batches, measure them, and if they match the ones I already tested, then I can be very confident in my assertions about their relative sharpness.
What I am asserting in my previous comment is not very high confidence. I was just saying, jokingly, but unironically, that PPI blade batches are more likely to match one another than subjective impressions are to match reality.
This isn't really that difficult to do. I have laid the whole process out hoping maybe someone else will also measure blades. If you really want to challenge the results, you could always provide some better measurements.
I'm just pointing out some things that are pretty well-understood regarding Statistics. I like what you've been doing for the most part. It's great that you are studying this. I might challenge when I see other people assuming certainty without sufficient evidence.
Statistics is based on mathematical principles that are universal. Statistical studies do not produce certainty, but a level of confidence for conclusions made about data with natural variability.
The sample sizes needed can be calculated once the variability in the data is known. I can tell you the sample size is greater than 1. It might be 10 or 20 or more. But to get high confidence, it would probably require automated testing and a big budget that is not realistic unless someone is really dedicated.
This should clear up any remaining questions:
I see a graph with five individual blades being tested. Each blade is being tested on multiple points along the edge after several passes through an artificial wear media. The force values along the edge are averaged. Is that right?
I am supposed to just meekly accept this like Moses has handed down the tablets of stone from Mount Sinai. Great.
Probability & Statistics, that's what I was writing about earlier. What can be inferred from the data, not the raw measurements. They are not the same thing.
Did you actually look at what the chart is saying?
…..it depends. I have used a vintage slim for the most part and I find perma
Sharps to be the best in it on lvl 7. The Astra sp and nacets are very close but I can sense tugging in my mustache with both that doesn’t happen with permasharp. Permasharp I can get 4 great shaves and 1 acceptable shaves in the slim. Astra sp and nacet only 3 lesser quality shaves.
I recently got a fatboy since everyone says it is better and can’t use permasharps in it too aggressive even dialed down. So I went to Astra so and it worked great in fat boy but only getting 3 shaves. Next week I plan to try the nacets in the fat boy to see before buying a large amount of Astra or nacet.
Very strange to me hearing all the wild variation between the experiences here but all seem to be positive atleast.
Sharps to be the best in it on lvl 7. The Astra sp and nacets are very close but I can sense tugging in my mustache with both that doesn’t happen with permasharp. Permasharp I can get 4 great shaves and 1 acceptable shaves in the slim. Astra sp and nacet only 3 lesser quality shaves.
I recently got a fatboy since everyone says it is better and can’t use permasharps in it too aggressive even dialed down. So I went to Astra so and it worked great in fat boy but only getting 3 shaves. Next week I plan to try the nacets in the fat boy to see before buying a large amount of Astra or nacet.
Very strange to me hearing all the wild variation between the experiences here but all seem to be positive atleast.
I'm not sure either of us is really listening, though it's probably just a misunderstanding. I'll take it to PM instead of arguing.
Did you actually explain it?
Or did you just post some graphs and leave it to people to make sense of them?
B.
