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Gap Sizes on Gillette Adjustables Are NOT All Created Equal

I have read that one too, but I disagree regarding that it would be this gap measurement that would be relevant to "aggressiveness" of the razor, which is why I asked.

The difference between "B" and "C" would only be like .001 or .0005 per measurement from my experience so I don't think it is that critical. I believe "C" might be more real world but I think there is more slop in the adjuster than .0005 or .001. and then there is the Gillette manufacturing variance.

Also, instead of trying to be super-critical about getting absolute measurements, I was just trying to get relative measurement so I could compare the various Gillette Adjustables I own against each other. For this purpose as long as I was consistent in my methodology across all the razors tested it was all good.
 
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Yes, the difference between A, B, and C is not much, but if (as someone in this thread suggested) others will measure the blade gaps of their adjustables in order to compare differences between razors of the same model but different years it makes sense to measure the same distance. Summing up the following factors may well make a difference: different measuring approaches, measuring tolerances due to the method (how clean, used or abused a gauge is), tolerances of the gouges themselves, skill of the one who uses the gouges (to some it ma not be that trivial to keep the points of two combined gouges closely together without at the same time wedging them between the relatively flexible blade and the safety bar).

Regarding which really is the aggressiveness-relevant gap I think it is not so important as long as we always compare the same.

The whole point of my asking was just to make clear in this thread, which approach you used, so that the measurements others maybe will make can be compared.
 
Yes, the difference between A, B, and C is not much, but if (as someone in this thread suggested) others will measure the blade gaps of their adjustables in order to compare differences between razors of the same model but different years it makes sense to measure the same distance. Summing up the following factors may well make a difference: different measuring approaches, measuring tolerances due to the method (how clean, used or abused a gauge is), tolerances of the gouges themselves, skill of the one who uses the gouges (to some it ma not be that trivial to keep the points of two combined gouges closely together without at the same time wedging them between the relatively flexible blade and the safety bar).

Regarding which really is the aggressiveness-relevant gap I think it is not so important as long as we always compare the same.

The whole point of my asking was just to make clear in this thread, which approach you used, so that the measurements others maybe will make can be compared.

You make excellent points. And I agree if people are going to spend the time doing this a consistent methodology will be best. By the way my feeler gauges were new out of the package. Once we start to collect some data points, statistical methods could be used to even out these errors. However I believe a correct minimum sample size is about 25 different measurements, so we will need at least that many razors of each type (assuming a normal distribution curve). Good luck getting that many people to data collect. But as I said, my measurements were enough to establish not all Gillette Adjustable models yield the same results i.e there are big difference between different model (and less differences between individual razors of the same model).
 
I would also point out that, measurement methodologies aside, blade gaps are only directly comparable when all other geometry of the razors' heads are identical. Any variations in the width of the guard plate, for example, would likely be far more significant than small variations in the gap under the blade.

The reason that increasing the blade gap makes the Gillette adjustables more aggressive is because it changes the relation of the blade edge to the plane between the cap and guard -- causing it to extend further beyond that plane, specifically. If that plane is different from one razor to another simply measuring the gap isn't going to tell you what you're looking for.
 
I would also point out that, measurement methodologies aside, blade gaps are only directly comparable when all other geometry of the razors' heads are identical. Any variations in the width of the guard plate, for example, would likely be far more significant than small variations in the gap under the blade.

The reason that increasing the blade gap makes the Gillette adjustables more aggressive is because it changes the relation of the blade edge to the plane between the cap and guard -- causing it to extend further beyond that plane, specifically. If that plane is different from one razor to another simply measuring the gap isn't going to tell you what you're looking for.

I see what you are saying, here's hoping that the head geometry on the Gillette Adjustable family of razors is so similar that simply measuring blade/guard gap will give an indication as to relative aggressiveness between models in the family.
 
Maybe a future version of the blade gap wiki page could try to present families of razors that have similar head geometry? Gents would still want to make comparisons between families, but that is a problem of its own.
 
Fantastic post, Thanks.

When I measured mine last weekend I tried to consistently use option B in the pic above. A seems to offer a larger reading and C a smaller. I think A allows the guage to drop in behind the safety bar or perhaps flex the blade a bit, which would allow for the larger reading.

I had always assumed that the wiki gap chart was an average of several razors but that would have required either an owner with multiple samples of the same razor or a collaboration.

I have 3 Slims and 3 Standard FBs; unfortunately, 2 of each are out for replating (1 each w/ Sam & Chris) so I don't have those available to measure. I also have a LH & SH Super at my disposal. One of the supers and the slim I have show differing gaps on each side so I'll have to set them before I can measure the full range of settings.

It would be nice if we could collaborate and update the wiki; at least as far as the adjustables are concerned.

It seems that you're measuring in inches instead of mm, do you have a preference and if so, why?
 
I see what you are saying, here's hoping that the head geometry on the Gillette Adjustable family of razors is so similar that simply measuring blade/guard gap will give an indication as to relative aggressiveness between models in the family.

Just looking at the Fatboy -> Slim -> Super Adjustable progression in your measurements would seem to argue against that, though. Generally speaking your measurements get larger across the full range from one to the next, even though that's exactly the opposite of what seems to be most people's experience with those razors. I think most people would agree that one setting on a Super is noticeably less aggressive than the equivalent setting on a Fatboy.
 
I think most people would agree that one setting on a Super is noticeably less aggressive than the equivalent setting on a Fatboy.

That's funny, I only have the one Super 84 and my experience has been that it has been a more aggressive shave than my Fatboy. I guess that's why mustering people to do gap size measurements might be good as it will get some of the subjectivity out of the equation. By the way, the TTC on my used Super 84 did not work well when I got it so I used mineral oil on it's throat to solve that problem. So my Super 84 could be an outlier too???

As far as preference to inches vs millimeters I have always used inches in my measurements so it is only an illogical tradition nothing more.
 
Fantastic post, Thanks.

When I measured mine last weekend I tried to consistently use option B in the pic above. A seems to offer a larger reading and C a smaller. I think A allows the guage to drop in behind the safety bar or perhaps flex the blade a bit, which would allow for the larger reading.

I had always assumed that the wiki gap chart was an average of several razors but that would have required either an owner with multiple samples of the same razor or a collaboration.

I have 3 Slims and 3 Standard FBs; unfortunately, 2 of each are out for replating (1 each w/ Sam & Chris) so I don't have those available to measure. I also have a LH & SH Super at my disposal. One of the supers and the slim I have show differing gaps on each side so I'll have to set them before I can measure the full range of settings.

It would be nice if we could collaborate and update the wiki; at least as far as the adjustables are concerned.

It seems that you're measuring in inches instead of mm, do you have a preference and if so, why?

Thanks for your post. I would definitely be interested in what others with robust collections of Gillette Adjustables come up with as far as gap size measurements. And I too think we could aspire to updating the wiki. Please do measure your collection. :thumbup1: Thanks again.
 
Glenn, first of all, thank for your efforts here in this thread.

I have made several failed attempts at recording meaningful data, but when making a second sampling on the same razors I experienced enough variation to undermine my confidence.
I will pick up a new set of gauges this week and try to hold off on the caffeine prior to my next attempt.:001_smile

Also is it agreed that measurements are to be gathered using method "B" as described earlier?
 
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Glenn, first of all, thank for your efforts here in this thread.

I have made several failed attempts at recording meaning data, but when making a second sampling on the same razors I experienced enough variation to undermine my confidence.
I will pick up a new set of gauges this week and try to hold off on the caffeine prior to my next attempt.:001_smile

Also is it agreed that measurements are to be gathered using method "B" as described earlier?

Yes, I think "B" method has been agreed to and conforms to the Gap Wiki instructions. Thanks again for your attempts.
 
I love the discussion, and am very grateful for the information. FWIW, I think it's important to keep in mind that (even assuming flawless measurement technique) the results apply to the individual razors in your collection. Does that mean that those razors left the factory in exactly that configuration? I wouldn't bet on that. Our vintage Gillettes have lived long and varied lives. Some, no doubt were treated well, others roughly used and abused. If we were able to collect measurements on a few dozen of each model, we might be able to see if there are consistent differences. I'll volunteer to measure my 2 Slims, 1 FB, and 1 SA, but I'd worry that my tools and technique may not be good enough.
 
My D4 Fatboy had the following:

Setting/Blade gap in mm
1 = 0.50
2 = 0.58
3 = 0.65
4 = 0.75
5 = 0.85
6 = 0.91
7 = 0.97
8 = 1.02
9 = 1.12
 
Any other takers? I would really love someone else with a Gillette Bottom Dial to take gap measurements just to double check me. Thanks.
 
OK Glenn, got a handful of measurements, using your form:
S
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t
t
i
n
g
F
a
t
b
o
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E
2
E
x
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c
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D
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M
4
A
r
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s
t
o
c
r
a
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S
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G
3
S
u
p
e
r

8
4

O
3
R
e
d

D
o
t

D
1
B
o
t
t
o
m

D
i
a
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F
4
T
o
g
g
l
e

D
1
C
h
r
o
m
e

T
o
g
g
l
e

F
4
1.011.014.019.024
2.015.017.022.025
3.017.021.025.028
4.019.026.029.031
5.025.028.032.034
6.030.031.035.037
7.033.033.038.040
8.035.036.041.043
9.037.040.044.047
Avg Gap.025.027.032.034



F
a
t
b
o
y

E
4
E
x
e
c
u
t
i
v
e

D
3
S
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i
m

M
4
A
r
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s
t
o
c
r
a
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S
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G
3
S
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p
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8
4

O
3
R
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d

D
o
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F
4
B
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D
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1 to 5

N
D
C
2nd

R
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d

D
o
t

D
1
S
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i
a
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T
o
g
g
l
e

4
1
0
6
1.008.010
1.5.011.014
2.013.018
2.5.016.022
3.020.025
3.5.023.026
4.026.029
4.5.030.033
5.034.036
Avg Gap.020.024




I'll fill in more blanks as I can.
It's Spring and I'm married to a Landscaper....:001_smile
 
Tom this is great! Thanks so much for doing this. It is interesting to see that your 5 Position Bottom Dial is a mild shaver. Your data shows my 9 Position Bottom Dial appears to be an outlier. Your Red Dot and Serial Toggle match well with what I saw when measuring mine so that is good and the Fatboys appear to match too. You are confirming that Red Dot's and 9 Position Bottom Dials give a wider blade gap then the Fatboys. Thanks again for doing this!!! :thumbup:
 
Very impressive research! Were all of these razors gapped this way purposely or were there just variants in the quality control that made each type vary in millimeters?
 
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