Did I just shave with the world's sharpest straight? (0.125 Cubic Boron Nitride)

[riooso]

I am in total agreement with you Abeck. One should go at this in a scientific, methodical way. The problem that I have found with shaving with a straight is that you can measure, magnify and generally do everything that you want to a blade to determine how it will shave but the deciding event is the "shave". Then there is the difference in beard density, thickness of individual hairs, pattern of growth, and how fast everyone's beard grows in a day. It is very difficult to quantify how happy everyone will be given any particular level of keenness with a particular 1/4 grind vrs full hollow razor......and so on. I use to approach honing scientifically and then a J-Nat came into my life and everything went out the window... I just had to accept the fact that I did not understand some things.


Thanks,
Richard

 

[superbleu]

Funny you should post this Abeck.
I was just thinking today of doing a double blind test with 4 identical razors honed exactly the same (as much as possible) and finish each with .5 micron diamond, .25micron diamond, .25micron CBN, and .125micron CBN. Use razors A, B, C and D for a set number of times and see what I find.

 

[Seraphim]

Well I am going to jump into it again! I have put the CBN paddle to most of my razors after using a very hard, dense, fine Asagi and I have to tell you I am getting all that I want from a straight razor. I don't need more, I really don't.

I hear talk about keenness this and keenness that when we are dealing with such fine grits. The following is model that I have been using for a little while now and some may not agree, but here goes. When you are into extra fine grits like 0.1 micron diamonds.....you get the idea, you are polishing the bevel not refining the edge. You may be destroying the edge by leaving jagged grooves in it but you are not refining it. That is the problem that I had with diamond film. I understand that felt helps a lot and I have not tried it. With hard felt you are trying to mask inherent problems that a diamond has, mainly extremely hard sharp corners.

Enter CBN. It appears to have almost a random structure and softer edges. These are exactly the same reasons that I starting using Japanese Naturals. J-Nats had random particle shapes and this fact has been touted by others as being one of the reason that J-Nats gave such smooth edges. I was having a hard time believing all that, but very quickly I proved to myself that I was wrong. One very hard thing for me to give up was the extremely polished edge that I got from diamonds on one hand but an edge that would slice you in a heartbeat. I really felt that diamonds turned my razor into a slicing serrated Ginsu knife on steroids but man they could cut cleanly!

I have been using CBN enough to know that it is the "missing" final step in my razor prep. It is easy and quick and the edge is very forgiving. I am happier every time I use it because it does not make me use any "special" techniques that I had to use with diamond edges. It may give you an occasional weeper but hey, that is not all bad!

Sorry to be so long winded and I did not want to expand on an already long vendor thread but it just works for me.

Take Care,
Richard

Ever try a sheet of wet paper under your lapping film? It has just enough give to really smooth out the diamond, while still maintaining a pretty uniform surface.

 

[Seraphim]

Funny you should post this Abeck.
I was just thinking today of doing a double blind test with 4 identical razors honed exactly the same (as much as possible) and finish each with .5 micron diamond, .25micron diamond, .25micron CBN, and .125micron CBN. Use razors A, B, C and D for a set number of times and see what I find.

How do you do a double blind, if you honed them and labeled them yourself?

 

[superbleu]

How do you do a double blind, if you honed them and labeled them yourself?

Easy, label them 1, 2, 3, 4. Then have someone else tape over them as A, B, C, D after I am done honing them.

 

[riooso]

Ever try a sheet of wet paper under your lapping film? It has just enough give to really smooth out the diamond, while still maintaining a pretty uniform surface.

Yes I have. It still comes down to the point that I, personally, do not like diamond edges. I assume that you have use a razor finished honed on a J-Nat? Just different tastes I imagine.


Take Care,
Richard

 

[Seraphim]

Yes I have. It still comes down to the point that I, personally, do not like diamond edges. I assume that you have use a razor finished honed on a J-Nat? Just different tastes I imagine.


Take Care,
Richard

I don't care for the feel of edges finished past 0.5um personally. And I have my own theories as to why. Last week I was shaving off a 1.0um diamond on cloth finish, and that seemed to work quite well for my whisker/skin combo. 0.5um feels a bit "fresher", but I haven't really gone ABAB experimentation to further refine what's what there.

Anyhow, I was simply suggesting the paper under film idea as another avenue of exploration if you hadn't tried it already.

I haven't shaved with a Jnat edge in a long long time, so I'm no authority on any of those finer points.

 

[honed]

Well I am going to jump into it again! I have put the CBN paddle to most of my razors after using a very hard, dense, fine Asagi and I have to tell you I am getting all that I want from a straight razor. I don't need more, I really don't.

I hear talk about keenness this and keenness that when we are dealing with such fine grits. The following is model that I have been using for a little while now and some may not agree, but here goes. When you are into extra fine grits like 0.1 micron diamonds.....you get the idea, you are polishing the bevel not refining the edge. You may be destroying the edge by leaving jagged grooves in it but you are not refining it. That is the problem that I had with diamond film. I understand that felt helps a lot and I have not tried it. With hard felt you are trying to mask inherent problems that a diamond has, mainly extremely hard sharp corners.

Enter CBN. It appears to have almost a random structure and softer edges. These are exactly the same reasons that I starting using Japanese Naturals. J-Nats had random particle shapes and this fact has been touted by others as being one of the reason that J-Nats gave such smooth edges. I was having a hard time believing all that, but very quickly I proved to myself that I was wrong. One very hard thing for me to give up was the extremely polished edge that I got from diamonds on one hand but an edge that would slice you in a heartbeat. I really felt that diamonds turned my razor into a slicing serrated Ginsu knife on steroids but man they could cut cleanly!

I have been using CBN enough to know that it is the "missing" final step in my razor prep. It is easy and quick and the edge is very forgiving. I am happier every time I use it because it does not make me use any "special" techniques that I had to use with diamond edges. It may give you an occasional weeper but hey, that is not all bad!

Sorry to be so long winded and I did not want to expand on an already long vendor thread but it just works for me.

Take Care,
Richard

Your findings are very similar to my own!
Very interesting indeed.

As an engineer, I find it a bit odd to see all these folks ready to jump on the CBN boat and party. I see a whole lot of uncontrolled testing going on and thus it is very hard for me and probably other readers, to reach any real conclusions. What about .125 polycrystalline diamond compared with .125 CBN? At tempuratures lower than 1,200 degrees or so, CBN should offer no advantage over diamond and it seems to be selling for more money. There are many questions that need to be answered, like: Which stropping surfaces are best? Are the products being used wet, moist or dry -which way is best? Are these "virgin" honing surfaces or have they been used before? How long is the product used before more spray is needed? How much is used? The CBN products that I see being sold are very expensive and I would love to see some real research. The only "studies" I have read are by vendors themselves and are obviously biased. Even the buyer of any product can be biased simply by the fact that they have bought it. This creates a "halo effect" in that person's mind which tends to lead them to embrace the product purchased.

I don't know about other folks, but as an engineer and, more importantly, as a shaver, I would like to see some REAL studies done by disinterested third parties using unidentified products. I realize that this would take some doing. A testing methodology would have to be agreed upon among the vendors and the neutrality of the testers/reviewers would have to be verified. But I think it would be to the benefit of the shaving public to have some unbiased facts.

I would challenge each vendor to provide a sample of their products for this kind of a test - those who will not should simply be noted that they have declined an invitation to participate. IMO, the results would make for some VERY interesting reading.

What do the rest of you think?

Sure, a fully scientific study would be great, but for me it holds no value.
For me it's all about the edge.

I've never seen any studies on J-nats or coticules either, still people rave about them.
Including myself.

There is so much variables within shavign with a straight, & after all, it's not science, it's shaving...

My own reasons for trying CBN was that I just love trying to "Perfect" the edge"
Actually, I could stop searching right know.
I have a variety of stones & pastes allready & I always get great to divine edges from them.
But this is a hobby for me & one of the things I love with that hobby is the ability to
doing endless experiemnts on your own.

And this forum is a great place for sharing them.
Not anyone of us posting positive results in this thread have any personal gain from giving CBN great reviews
we do that for letting others know what worked great for us.
Something you see in all the sub-forums here, people loving, liking or hating a certain soap, balm,
cologne, coffee-grinder or kitchen knife..

Turning this funny, interesting tinkering/testing into science would kill all the fun for me.

As we usually say YMMV

I will certainly test CBN & nanometer diamond compounds further & I will force my impressions of them on you all!

I'll end this ramblings with the words of one of the smartest people ever walking the earth:
"Hell, there are no rules here-- we're trying to accomplish something".—Thomas A. Edison

Ever try a sheet of wet paper under your lapping film? It has just enough give to really smooth out the diamond, while still maintaining a pretty uniform surface.

I did try out the lapping films a while back, including your trick with the paper underneath.
The edge I got was very similar to a low micron diamond spray edge.
For me it needed some additional CrOx stropping to be pleasant enough.
But, the lapping films sure are a great way to finish a straight in very fine grits, for a very low cost.

 

[jendeindustries]

Riooso - Ken, who sells the CBN, actually formulated it for knife sharpening! The fact that is was used on a razor was actually a fluke in another thread when BC and CBN got mixed up, thus leading to the experimentation on straights. It's been pure fun since, and honestly, I'm surprised so many people are liking it this much.

Anyway, Ken is a complete mad scientist, and I'm sure you and he would get along amazingly well with making the experiment extremely scientific (I've glazed over a few times with him, and that's hard to do!).

 

[Seraphim]

We've got SEM pics of the CBN itself, let's get some before/after pics of a razor edge!

We want pics!
we want pics!
we want pics!

 

[honed]

We've got SEM pics of the CBN itself, let's get some before/after pics of a razor edge!

We want pics!
we want pics!
we want pics!

I can sure send you a razor once I have all gear & got everything worked out.
You have taken really nice pics of edges before.

But I do have two concerns with that.

One is that I am planning to use Heljstrand MK#31's for these testings.
Can I trust you with one of these?
I mean since it all ready has a thumb-notch, God knows what you will subject it to with that Devil-Dremel of yours

And the other concern is... You can't shave with pictures, can you

 

[ambrose]

Craig

Send me a blade or two and Ill hone them up and finish on this purple magic. Then you can take some sweet pics and have your own experimenting

I think you will like it since the particle shapes seem similar to chome ox shape. Its imparts a sharper edge with the type of profile of chome ox.

 

[Seraphim]

Craig

Send me a blade or two and Ill hone them up and finish on this purple magic. Then you can take some sweet pics and have your own experimenting

I think you will like it since the particle shapes seem similar to chome ox shape. Its imparts a sharper edge with the type of profile of chome ox.

Aha!

Yes, this would solve me not having to find a second place to put a thumbnotch on honed's Mk31....

And it could serve as a possible double blind test.

I'll hone up two of Shanghai's finest, label them "A"&"B", then send them off to you. You finish one off on the dylithium crystals, cover the A and B over so I can't see which is which, and send them back to me. I'll take scope pics, then saw away at my whiskers and see what's what....

 

[ambrose]

Sounds like a plan, Ill send them back with a with a loaded piece of balsa for even more playing back at your lab

 

[honed]

Aha!

Yes, this would solve me not having to find a second place to put a thumbnotch on honed's Mk31....

And it could serve as a possible double blind test.

I'll hone up two of Shanghai's finest, label them "A"&"B", then send them off to you. You finish one off on the dylithium crystals, cover the A and B over so I can't see which is which, and send them back to me. I'll take scope pics, then saw away at my whiskers and see what's what....

Sounds like a plan, Ill send them back with a with a loaded piece of balsa for even more playing back at your lab

All in the name of good science Great show folks!

 

[jendeindustries]

Excellent idea, Ambrose

 

[riooso]

I will bet you dollars to doughnuts that you will know which one is the CBN blade by the time you finish your first cheek! I would like to see the results of that one.


Later,
Richard

 

[ken123]

Razor pics is a bit different. At the very least, you would be sacrificing the razor itself for 'the cause', since only a small piece would fit into the chamber and the handle would probably have to go (outgassing problems,etc). I'm probably going to pass on this. Even getting the SEMs of the compounds took a bit of doing. Can't say I'm not curious to see some SEM razor pics myself.

---
Ken

 

[Neurotopia]

I just broke a razor a few days ago, shattered it in half. I can submit a chunk to the cause if you like, only thing is that it hasn't been honed up in I don't know how long.

 

[Seraphim]

I do have access to a lab quality 1,000x Olympus optical scope. I'll see if I can get any good shots on there, although the depth of focus is pretty shallow it should at least be able to resolve the edge pretty nice.