Blade Comparison - A Blinded Study

Perhaps there is nothing in shavedom more controversial than blade preference. Like most people on B&B, I own several different variety of blades and I have my favorites. I could describe to you what I like and dislike about each individual blade, and I could tell you without hesitation that my favorite blade is the Polsilver SI. I must admit that I am somewhat baffled when other people disrespect the Polsilver or choose a blade that I find to be unusable. When it comes to blades, YMMV rules the day.

Over the years I have done my shave of scientific research, and the problem with the evaluation of shaving equipment is what is referred to as Experimenter Bias. Humans are unable to objectively evaluate pretty much anything. We have preconceived likes and dislikes that work at both the conscious and subconscious level. As applied to blade evaluation, if the shaver is aware of which blade is in the razor, an objective evaluation is impossible. In order to do an objective evaluation the shaver must be "Blind" to the blade in the razor. To that end I enlisted my wife to change razor blades after each blade was used for 3 days. At no time did I know which blade I was shaving with. As she believes this whole shaving thing is nutty, she has no experimenter interest in the outcome of the experiment.

The Experiment:

4 different razor blades.

*Polsilver SI
*Nacet
*Gillette 7 O'Clock Black
*Gillette Rubie Platinum Plus

I am very familiar with all 4 blades. Before the experiment I would have said the following:

1. Polsilver SI - My favorite blade. The best combination of sharp and smooth.
2. Nacet - Not quite as sharp as the Polsilver. Not quite as smooth. A small step beneath the Polsilver
3. Gillette 7 OC Black - Very sharp. Not smooth enough. Often irritating to my skin.
4. Gillette Rubie - 2nd favorite blade. Not quite a Polsilver but very close.

As with any good scientific experiment, I tried to keep as many variables as possible constant.

*24 hour beard
*ATT S2 razor
*Prep that included a pre-shave shower; Mickey Lee Shave Butter; Mickey Lee Drunken Goat Soap; Rudy Vey/ShaveMac D01 3 band brush; and Soap Commander Integrity AfterShave Balm.
*Each blade got a 3 day evaluation. My wife changed the blades. I was never aware of which blade I was using.


My goal in this experiment was twofold:

1. I wanted to learn if I could identify each blade.
2. I wanted to identify the best blade without experimenter bias interfering.

Blade Evaluation:

Below is a summary of my evaluation as well as my best blade guess.

Blade #1
-Very sharp. Good audible feedback. Not the smoothest. A few weepers here and there. Skin irritation after 3 days of use.
BEST GUESS - Gillette 7 OC Black. OVERALL RANK #4

Blade #2
-less sharp than #1 but much smoother. Nice combination of sharp and smooth. No irritation. No weepers. Quiet blade. Really nice blade. BEST GUESS - GILLETTE RUBIE PLATINUM. OVERALL RANK - #2

BLADE #3
-Not as sharp as #1. Not as smooth as #2. A bit of tugging. Good audible feedback. No weepers. Good shave just not as good as #2. BEST GUESS - NACET. OVERALL RANK - #3

BLADE #4 -
-Smooth and Sharp. Very efficient shave. No irritation. No weepers. Very quiet blade. My favorite blade.
BEST GUESS - POLSILVER SI. OVERALL RANK - #1



RESULTS:

I was surprised when my wife showed me the blade chart. I didn't get a single blade right. NOT ONE!!


ACTUAL BLADE (final ranking)

BLADE #1 NACET(4)
BLADE #2 POLSILVER SI(2)
BLADE #3 7 OC BLACK(3)
BLADE #4 Gillette RUBIE(1)



CONCLUSION:

So there you have it. To my surprise, I was unable to identify a single blade despite having used all four blades extensively in the past. My clear favorite was blade #4, and I was quick to assign the Polsilver SI to that spot. I was also surprised to find that the Nacet was my least favorite blade. I would have put the Gillette 7 OC Black in that spot before the study.

A hearty congratulations to the Gillette Rubie Platinum Plus, my new favorite blade, on its well earned victory.


By the way, more than ever, my wife thinks this is a nutty hobby.

I really liked your methodology...I'm very tempted to try this!

Thanks for sharing.

Fantastic study! Thanks for the post. Although you did not identify any, your top two were still your top two. That's something.
I would love to see further study- to see if your take on the blades are consistent, or if other factors determine the outcome.
Also, I think it would benefit the study to not know that each 3 days is a different type blade. Allow for the option of putting in a new blade, but of the same type.
Maybe I can get my wife to give this a try. She thinks I'm nutty, too.
Thanks again for the study.

Natchez14 said:

Fantastic study! Thanks for the post. Although you did not identify any, your top two were still your top two. That's something.
I would love to see further study- to see if your take on the blades are consistent, or if other factors determine the outcome.
Also, I think it would benefit the study to not know that each 3 days is a different type blade. Allow for the option of putting in a new blade, but of the same type.
Maybe I can get my wife to give this a try. She thinks I'm nutty, too.
Thanks again for the study.

Click to expand...

I agree with you. The good news is that I was able to distinguish my top two blades from the rest of the pack. My bias showed when I identified the best blade and concluded that it must be the Polsilver.

The next experiment will be to compare the Polsilver to the Rubie directly. It would be fun to learn if in a blind trialI could identify the correct blade if the blades in the experiment followed a more random pattern. For example, in a six day trial the Polsilver is in the razor on days 1,5 and 6 and the Rubie is in the razor on days 2,3 and 4. My guess is that I would not be able to identify the blade on any given day, but who knows?

It was a fun trial. I will take a few weeks off and go at it again.

Very cool study, thank you for sharing.

I've never actually tried it, but I'm 100% sure that if I tried a blind test between 2 blades, I'd pick the correct one 50% of the time. Interesting write up, though. Your results were exactly what I predicted after reading the experiment. Thanks for sharing this.

aldomarino said:

I've never actually tried it, but I'm 100% sure that if I tried a blind test between 2 blades, I'd pick the correct one 50% of the time. Interesting write up, though. Your results were exactly what I predicted after reading the experiment. Thanks for sharing this.

Click to expand...

My uncle has 4 daughters. You would think that he would get their names right 25% of the time, at the very least. The truth is he never gets it right.

Natchez14 said:

Fantastic study...your top two were still your top two.

Click to expand...

Exactly. I'll bet if you threw something you didn't have experience with and/or didn't like very much, that you would be able to identify it fairly quickly. If someone blindly loaded my razor with an Indian Gillette Wilky, I'd know about it on the first swipe of the razor. But ask me to blindly decide between my top 3 or 4 and I probably would have had the same experience as you.

To honor the glorious victory of the Gillette Rubie Platinum Plus, I put in an order for another 200 blades. Not that I needed more but it seemed like the right thing to do. I am set now for several millennia. No more blades. (as I recall, I have said that before.....)


I generally avoid temptation unless I can't resist it.
― Mae West

I really liked this study, and you kept it honest by using a double-blind. (That's better than I've ever done.) I'm convinced.

Frankly, over a three-day shaving period, a lot of guys would have the same problem distinguishing between blades. Point well-taken.

However, if the shaving period is a week, I'm pretty sure I'd be able to distinguish between my personal favorite blades (Feather, Personna Med Prep, GSB). I could instantly tell when I used a GSB, though it might take a few days to tease the differerences between the Feather and Med Prep.

It's much easier to distinguish between blades if you're using an aggressive razor, but nearly impossible if you're using something mild like, say, a Gillette NEW.

With a Kai, the difference would be detectable within seconds.

poikkeus said:

I really liked this study, and you kept it honest by using a double-blind. (That's better than I've ever done.) I'm convinced.

Frankly, over a three-day shaving period, a lot of guys would have the same problem distinguishing between blades. Point well-taken.

However, if the shaving period is a week, I'm pretty sure I'd be able to distinguish between my personal favorite blades (Feather, Personna Med Prep, GSB). I could instantly tell when I used a GSB, though it might take a few days to tease the differerences between the Feather and Med Prep.

It's much easier to distinguish between blades if you're using an aggressive razor, but nearly impossible if you're using something mild like, say, a Gillette NEW.

With a Kai, the difference would be detectable within seconds.

Click to expand...

I read your work from 2014 and it was a very impressive trial. A few thoughts: First, I chose 3 days so that the study would end in a reasonable amount of time. Of note, my impression of a blade did not change over the 3 days. If I had done a 1 day trial for each blade, my results probably would have been the same. Second, before my study I would have said, just as you said, that I would be able to distinguish between blades. That assumption proved to be false. As it turned out, I could distinguish my two favorites (polsilver and rubie) from the laggards, but the gap was much much wider than I imagined. Before the study I would have said that all 4 blades were really good blades. To my surprise, the study demonstrated that the quality gap between the best blade(Rubie) and the worst(Nacet) was quite large. How is it that I like the Nacet in an open trial, but dislike the Nacet in a blinded trial? I believe the answer is that "Experimenter Bias" is powerful.

I suggest that you do a blind study. If my experience holds true, the results will surprise you.

Excellent work. Thanks for sharing. I think most guys here could pick their top 2, but couldn't ID them specifically.

That's a reasonable request, and should be kind of fun. However, I usually toss my blades after maybe six days, or whenever the edge goes.

I'll use GSB, Personna Med Prep, Feather, and (for purposes of amusement) a Personna Lab. I'll shave for about six days, and I'll report my results here.

I've never tried the Rubies. Now I will. Currently, my favorites are GSB, and Personna Med Preps. I would love to try this test, but I travel so much, my environment would be a definite factor. It's amazing how bad the bathroom lights are in most hotels.

Good post, but I'll stick with Polsilver SI.

gus1942 said:

Good post, but I'll stick with Polsilver SI.

Click to expand...

I have no dog in the fight, but if you want to try a few of the Rubies, send me a PM.

Well, since this study agrees with my bias, in that Rubies are my new favorite blade beating out the Blacks, GSB and Polsilver, I wholeheartedly approve.

I'd be curious to do the blind thing too, I'm just not sure I want to give my wife any more reason to think I obsess too much over shaving.

Are Gillette Rubies still in production?

stovepipe699 said:

Are Gillette Rubies still in production?

Click to expand...

They are still in production but there are no vendors in the USA/Canada that I am aware of. There are several Ebay retailers from Russia and Lithuania with good track records. There were reports of fake Rubies coming out of China so I would stick to a retailer with a positive history. If you want to give them a try, shoot me a PM and I will be happy to send you a few blades.


You only live once, but if you do it right, once is enough.
― Mae West

Great post.