Thin Cap Gillette Old Type - most technically correct design ever?

[sakaltras]

The issue you will have with plastic 3D printing is that the processes which use materials robust enough to make the razor useable probably won’t be accurate or detailed enough. And the processes which are capable of providing the accuracy and detail, don’t use materials that are robust enough. The metal 3D printing process could do it, but the finish won’t be to expected consumer standards I wouldn’t think, and the thread action would not be very smooth. But I could be wrong.

Blackland now has a razor which they claim is 3d printed stainless steel if not I'm wrong. Maybe such a printing only pays off when considering large numbers. Don't know. If never ever did 3d printing so no experience at all. Was only an idea...

 

[RDM]

Three things:

1) We could and probably should stick with the word micron to avoid confusion in print, but spoken the two words do not sound alike. The instrument is pronounced my-KROM-muh-ter while the distance is pronounced MY-kroh-me-ter. (By the way, kilometer, while often mispronounced, is actually pronounced KILL-oh-me-ter. The incorrect pronunciation is from falsely equating the word with instruments like the common speedometer that is also spelled with an 'o' right before the 'meter.' We don't say mill-LIM-uh-ter or cen-TIM-uh-ter; similarly, there is no reason we should say kill-AHM-uh-ter.)

2) The discussion of blade gaps in Gillette adjustables is interesting, but it should be noted that the gaps of the various razors is not the same. For example, setting 3 on a standard D4 Toggle has approximately the same gap as setting 6 on a standard Fatboy from the same year.

3) Yes, the British flat-bottom New is a fantastic shaver.

I’m not sure which Gillette Adjustable the chart is for. It is however, I believe, defining blade exposure rather than blade gap. Blade gap is relatively easy to measure using feeler gauges, blade exposure, not so much.

 

[RDM]

In trying to determine what might be the correct blade exposure dimension for the Thin Cap Old Type I'm modelling, I've disappeared down a bit of a rabbit hole, but think I'm getting closer to a figure I feel comfortable about. It doesn't make it easy that most manufacturers don't specify blade exposure dimensions, so it's difficult to try and make comparisons to get a reasonable ballpark number.

By accurate measuring and construction of 3d geometry of the Thin Cap Old Type my best guess for the blade exposure dimension is between 0.07mm and 0.1mm.

Testing this by mock shaving a cork surface and feeling the amount of bite that different razors exhibit I can also report the following.

Merkur 1904: Negative blade exposure. No bite at all, so it's not much of an Old Type replica, apart from its appearance. It's hard to break the skin with this one unless you push hard, or navigate over small radii surfaces.

Gillette Fat Boy: Positive blade exposure from Setting 3 onwards, and negative/zero on Settings 1 and 2, which doesn't strictly agree with the settings on the chart, but the numbers are so low that it could easily be due to build tolerances, or the chart is for another Gillette Adjustable model.

Gillette Thin Cap Old Type: Positive blade exposure. This actually feels like my Gillette Fat Boy on about 4 or 5 when tested on the cork surface. According to the chart settings this would mean a blade exposure dimension between approximately 0.1mm and 0.12mm. But given that my Gillette Fat Boy seems to be operating a little more mildly than the chart settings would indicate, my estimation of 0.07mm to 0.1mm seems to be pretty good.

For comparisons sake the Henson medium aggression model is listed on their website as having a blade exposure dimension of 0.05mm.

I'm confident enough now that if someone were to make the razor I've modelled, it should provide a reasonable shaving representation of a Gillette Thin Cap Old Type. I'll post the files here when I've finished.

 

[sakaltras]

Rotbart seems to come very close to the design. It seems to be a mix between Gillette Old Type and NEW SC.

Will give a run today. I really like my Old Type with a shim. Hope the Rotbart works without.

Sami

 

[RDM]

 

[RDM]

Here are the STEP files you can use for CNC machining for all of the above if anyone is interested. The M5 thread will have to be tapped post machining.

 

[RDM]

And although the design, as it is, will not be suitable for all types of 3D printing machines, here are the STL files as well. Same goes for the M5 tapping.

 

[sakaltras]

And although the design, as it is, will not be suitable for all types of 3D printing machines, here are the STL files as well. Same goes for the M5 tapping.

Thank you very much for your effort!!

 

[RDM]

Thank you very much for your effort!!

You’re welcome.

It has just occurred to me that the Gillette Tech cap is quite thin, and I should be able to create an easily 3D printable design for a Gillette Old Type style base plate to match it, resulting in the same 0.07mm blade exposure, zero blade gap and blade edge clamping. That way you won’t have to bother printing a cap, assuming you have a Gillette Tech laying about. Let me look at that tomorrow and see what can be done.

 

[Cesare]

Incredible thread!

Thanks, @RDM, for bringing the subject up. Impressive work and knowledge!

And thanks, @BigSpender, for making the comparison between the BIC Sensitive (THE best cartridge by far, IMO) and the Old Type.

I took a BIC out for a ride today and was reminded of just how good it shaves and feels. If that’s what an Old Type shaves like, I may start looking for one!

I use a Brazilian Goodwill, which I’ve been told is based on the NEW SC. Would you say the BIC is more similar to the Old Type than this Goodwill?

I’m assuming the subject’s been discussed before, but what was the idea behind going from the Old to the New Type, back in the day?

Some pictures:

 

[RDM]

OK. Here's a base plate design suitable for use with a Gillette Tech cap, which will give the same blade exposure as the Gillette Thin Cap Old Type, and is suitable for all 3D printers. Let me recheck for mistakes before I post the STL files.

 

[RDM]

STL file for 3D printing is now done. If anyone does end up printing this could they please report back on any design issues, and of the shaving performance when used with a Gillette Tech cap. Thanks.

 

[Tanuki]

I don't know what you are talking about, though maybe you do.

But I do know how wide 0.001mm is. It is just barely big enough for one wavelength of light to pass through.

I do know that 0.009mm is wide enough to allow a strand of spider silk through.

I'm pretty sure that most people's whiskers are wider than a spider web, though I could be wrong. I often am. (However, if a spiderweb strand were as thick as a human's whisker, would we be able to cut it with a razor blade?)

I also know that 0.1mm = 1/10th of a millimeter.

0.01mm = 1/100th of a millimeter.

0.001 = 1/1000th of a millimeter.

What, you don't believe me? You say, that's just your opinion. I am entitled to my own facts.

Perhaps this will be helpful:

View attachment 1292036

Or maybe not. I just found it on the Web in a set of images, so I cannot attest to its veracity.

I don't mean to look like a know-it-all, but I also know that 1/1000th of a millimeter is called a "micron," aka "micrometer." (Some birdbrain with the metric standards nomenclature "If it ain't broke, let's fix it" committee came up with the brilliant idea of changing the name of a "micron" to a "micrometer." What else is called a "micrometer"? That little caliper screw thingy that measures very small distances.

If "meter" means measure, and "micro" means very small, what's the Latin or Greek word for "thingy"? According to Google Translate, thingy in Latin is thingy. However, in Greek it is σκατά, pronounced skatá, which it so happens is a primary four-letter expletive in Greek, so I don't think the Metric Standards NIIABLFI committee will go for it. (However, if you want to curse in public without repercussions, remember: skatá! Not recommended if you are actually in Greece.) "However, "thing" in Latin is "rem." So perhaps they could rename the micrometer thing, micrometerrem, to distinguish it from the unit of measurement, micrometer, that used to be called micron. Or not. I can figure out which is which, probably because I am a human. But I'm afraid this is going to confuse online search engines, which are not.

But what really puzzles me is why, if, like the original, your Gillette Old Type Mk II will have no blade gap, are you talking about blade gaps on a Gillette adjustable? I can't think of two more completely different razors.

Now, if you could make an "adjustable" that looks and shaves like an Old Type, you might be on to something. Of course, one way would be to allow the user to slide the blade from side to side to customize the blade exposure. Or you could come up with a vernier dial screw adjustment to do it with the absolute precision, down to 0.01 nanometers, that B&B members demand from a $50 razor. Just be sure to plate it in rhodium.

Early nominee for post of the year 2021

And, yes, rhodium plating is required.

 

[sakaltras]

STL file for 3D printing is now done. If anyone does end up printing this could they please report back on any design issues, and of the shaving performance when used with a Gillette Tech cap. Thanks.

I really appreciate your work. Is this the last version of the STL file?

I going to ask a 3D printing service for the price for printing this in stainless steel or aluminium. I was not aware that printing metals is possible but on their website they claim that they can do this... Btw Blackland also announced that the next stainless steel razor will be printed rather than CNC machined.

 

[RDM]

I really appreciate your work. Is this the last version of the STL file?

I going to ask a 3D printing service for the price for printing this in stainless steel or aluminium. I was not aware that printing metals is possible but on their website they claim that they can do this... Btw Blackland also announced that the next stainless steel razor will be printed rather than CNC machined.

Yes it is.
I sent the file off a month ago to have it printed in plastic to check that it was OK design wise, but because of some issues with the company I sent it to I still haven't received it yet.
I was hoping to be able to confirm the design before anyone spent any serious money on it.

 

[sakaltras]

Yes it is.
I sent the file off a month ago to have it printed in plastic to check that it was OK design wise, but because of some issues with the company I sent it to I still haven't received it yet.
I was hoping to be able to confirm the design before anyone spent any serious money on it.

I really like your design and I'm strongly interested to know if this could be a modern version of the old type. The idea to combine it with a tech cap is really exciting. So please keep us informed.

Thanks!

Sami

 

[santamariasteve]

Yes, there are folks who think the Gillette Old Type thin cap was Gillette's crowning achievement. There also are folks who think the Ford Model T was the American automobile industry's best product (setting aside the issues of much slower speed and reliability).

All points of view have some merit with some persons. I no longer know what is true. And besides, what is truth? When I was 25 I knew exactly what was truth. Now that I'm 85 truth is a concept that is less than consistently clear.

 

[RDM]

Yes, there are folks who think the Gillette Old Type thin cap was Gillette's crowning achievement. There also are folks who think the Ford Model T was the American automobile industry's best product (setting aside the issues of much slower speed and reliability).

All points of view have some merit with some persons. I no longer know what is true. And besides, what is truth? When I was 25 I knew exactly what was truth. Now that I'm 85 truth is a concept that is less than consistently clear.

Doubt is not a pleasant condition, but certainty is absurd - Voltaire

 

[RDM]

It finally arrived. Seems dimensionally spot on, and everything fits as it should.

Test shave to follow.

 

[Anu]

I really appreciate your work. Is this the last version of the STL file?

I going to ask a 3D printing service for the price for printing this in stainless steel or aluminium. I was not aware that printing metals is possible but on their website they claim that they can do this... Btw Blackland also announced that the next stainless steel razor will be printed rather than CNC machined.

Yep, they do since ca. mid 90's, available only to a select clientele ca. early 00's and commercially accessible ca. early '10. Now, there are lots of services available for SLS (Selective Laser Sintering), one problem though, without pp the surfaces are inherently porous. It could be hot isostatic pressed, albeit highly impractical for this particular set of geometries though, or conformally coated.