Thread: Glass razors?

I have a ceramic kitchen knife and its great however because of its design you can't hone it yourself even with diamond hones. It has to go back to the factory and thats the real issue with it. I've told my wife and kids anyone caught using that knife but me will be shot on sight. The blade is very light like nothing, and the slightest torque or spill will destroy it. I don't think ceramic would be practical for a razor. You couldn't strop it or hone it. yes it would last a long time and then there is that brittle edge and microchipping.

Originally Posted by thebigspendur

I have a ceramic kitchen knife and its great however because of its design you can't hone it yourself even with diamond hones. It has to go back to the factory and thats the real issue with it. I've told my wife and kids anyone caught using that knife but me will be shot on sight. The blade is very light like nothing, and the slightest torque or spill will destroy it. I don't think ceramic would be practical for a razor. You couldn't strop it or hone it. yes it would last a long time and then there is that brittle edge and microchipping.

Do you mean because of the curvature of the blade of your kitchen knife it can't be honed even with diamond hones or are you saying ceramic blades in general can't be honed with diamond hones? If so, why not?

Chris L

I've had a piece of obsidian, and it is indeed impossible to knap it straight.
Of course if you are very skilled you could perhaps knap it to something that looks reasonably straight, but it would still be serrated, and dangerous as hell.

Perhaps it is possible to knap a piece of obsidian, and get a fingernail sized smooth curved edge.
You could mount it on a twig and shave with it, DE style. Now that would be something to see

Originally Posted by wopmanfixit

Glass is a liquid with extremely high viscosity. Is glass liquid or solid?

"There is no clear answer to the question "Is glass solid or liquid?".... Nevertheless, from a more common sense point of view, glass should be considered a solid since it is rigid according to everyday experience."

from "Conclusion"...last paragraph in the article.

Evidently a matter of 'preferred' interpretation.

Some people consider glass a liquid because the crystalization process lasts lifetimes. I.e. plain glass is forever locked in a phase change. Or so I've heard.
You might as well call a tree 'liquid'.

The ceramic kitchen knives are meant to be sent out to be shaprened by the manufacturer, IIRC.

Thanks Craig.

No, I didn't try those guys, but I kinda lost hope because the time involved to develop a "new technology" is just unreasonable for me right now.

Those razor blades are probably as close to being usable as we're likely to get, but theres no guarantee that a smooth edge is possible either. It may be possible to use lapping pastes to get the edge down to sub micron sharpness but the grain of the ceramic would have to be extremely fine as well, which is something I have no knowledge of currently.

Originally Posted by Bruno

I've had a piece of obsidian, and it is indeed impossible to knap it straight.

This is not true, look at the microlith technology of the central america's. They took a single core and shaped it so that thin straight blades could be flaked of repeatedly.

Also many people like smiling blades.

Originally Posted by The Blacksmith

"There is no clear answer to the question "Is glass solid or liquid?".... Nevertheless, from a more common sense point of view, glass should be considered a solid since it is rigid according to everyday experience."

from "Conclusion"...last paragraph in the article.

Evidently a matter of 'preferred' interpretation.

Well the best answer is really glass is a glass. There are interesting things being done with glasses made out of metals, it is an active area of material science.

The other point is that glass has not been shown to flow at average temperatures.

So if it flows it might be in the mm per millions of years level, but it does not flow in any as yet measured way.

Originally Posted by PonderingTurtle

This is not true, look at the microlith technology of the central america's. They took a single core and shaped it so that thin straight blades could be flaked of repeatedly.

Also many people like smiling blades.

The problem is not that it is curved (which I like) but also that it would likely have a warp as well.
It would be similar to shaving with a sharpened spoon.

Also, you might get thin straight blades, but when you knap them to get a razor's edge, they won't be straight anymore.


Of course I might misunderstand what you mean, so do you have a link that contains some pictures?

Originally Posted by PonderingTurtle

This is not true, look at the microlith technology of the central america's. They took a single core and shaped it so that thin straight blades could be flaked of repeatedly.

Also many people like smiling blades.

a picture of some prismatic blades.
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