Thread: The differences among finishing stone.

Originally Posted by onimaru55

I think this is why So only likes to sell what he considers hard stones to razor folks ie to keep the bevels as true as possible.

Well that is also interesting. I have an Escher with a label on one end that says 'yellow/green and on the other end a label that reads 'guaranteed soft'. This stuff can get confusing.

I do not have a way to test this but one idea that I have not
seen posted is that as the slurry drys it keeps the spine
from touching the hone and lifts the spine a little. Additionally
the slurry gathers ahead of the edge and as the edge rides up
on the micro marbles they cut more aggressively at the front
of the bevel and generate a false bevel. Combined the slurry in
front of the edge and the slurry under the spine could and adjust
the apparent/ effective angle of the edge as much or more
than a layer of tape would (+/-)

Coticule garnets pulverize and change dimension (finer) in the slurry
and act differently as the honing progresses. I suspect the spine is key
in this pulverizing action -- tape would reduce this effect. When rinsed
of slurry only the rounded tops of the garnets scratch the steel. This
is a good thing especially when a little lather and a soft hand is used.

Silt and slate stone hones like the Chinese 12k have micro grains of quartz
that are tougher and do not pulverize. Combined with the clay mud they
would support the spine a lot higher and bounce more along the front
bit of edge.... Think marbles in pancake batter. Some quartz grains
are very round and very fine and when well held by a sturdy matrix they
do not scratch deeply.

Rinsing the slurry lowers the spine and presents the cutting edge
to the very top of the hard bits hidden in the hone. For a lot of razors this is
is the best final step.

Barber hones may have coarser bits but only the top of the grains
are exposed. A little lather helps the blade skip across the tiny tops
to good effect as does a skilled light touch. Some barber hones
have finer bits than others... Arkansas hones are in the skip across
the top class of hones.

Modern man made hones... a light slurry cuts very fast. The grains
do not pulverize but are finer to start (10K/12K). Rinsing the
slurry again presents the sharp noses to steel for an even finer
finish.

Jnats... I have almost no clue -- someone please send me a dozen
to I can spend the next year learning a bit about them.. I will
pay return postage

I said I have no way to test.... one way is to take a microscope
and inspect the slurry. All the minerals need to be checked
especially the harder sub micron bits. Big floppy flat clay grains are
almost a do not care but they dominate many of the micro photographs
I have seen. They are important in how the slurry works and
presents the durable hard bits to the steel.

Originally Posted by JimmyHAD

Well that is also interesting. I have an Escher with a label on one end that says 'yellow/green and on the other end a label that reads 'guaranteed soft'. This stuff can get confusing.

Hmmm... I know nothing about desirable traits in Eschers. May be a relative term or marketing ? Does this soft Escher require more frequent lapping than other finishers ?

Originally Posted by niftyshaving

Coticule garnets pulverize and change dimension (finer) in the slurry
and act differently as the honing progresses. I suspect the spine is key
in this pulverizing action -- tape would reduce this effect. When rinsed
of slurry only the rounded tops of the garnets scratch the steel. This
is a good thing especially when a little lather and a soft hand is used.

Only thing I would fix there is garnets do not cleave--hence the extreme slurry-dulling effect you get on a coticule.

I get the same microbevel look on my Jnat too--requires slurry to do anything. If I only go 1-2 rounds, it does look like I used tape on the edge. I always stick to pretty much no pressure on that stone, as it has a way of sucking a blade to the surface.

Have the bevels gotten taller as they've gotten thinner Sham?

That is the only explanation that makes sense to me... One way or another more steel is being taken off of the thin ones. I can only speculate as to the cause (but I can think of a few causes where this could happen irrespective of the geometry of the edge in relation to the spine). But... If they are getting thinner, they should also be getting taller.

Originally Posted by HNSB

Have the bevels gotten taller as they've gotten thinner Sham?

if i understand your question right You mean by taller --bevel gets wider?
is this correct?
if yes then this is the answer.
You know when you hone the blade as you move higher grits your edge gets finer --narrower-- and bevel is getting thinner or narrower right(thickness of the steel on bevel level)?
respectively.
Now are there any way some stone could make edge finer-narrower - but will make bevel less narrower(thickness of the steel on bevel level) when you compare another stone edge?
this is the part i am having trouble.

Originally Posted by hi_bud_gl

if i understand your question right You mean by taller --bevel gets wider?
is this correct?
if yes then this is the answer.
You know when you hone the blade as you move higher grits your edge gets finer --narrower-- and bevel is getting thinner or narrower right(thickness of the steel on bevel level)?
respectively.
Now are there any way some stone could make edge finer-narrower - but will make bevel less narrower(thickness of the steel on bevel level) when you compare another stone edge?
this is the part i am having trouble.

You understood correctly. Since we are talking about the thickness of the bevel in two different dimensions, I wasn't sure what word to use.
All else being equal, if two different stones leave bevels of different dimensions, they are abrading the steel differently. That, in my mind, is certain.
The cause is the part that requires speculation... If I get some time I will draw some pictures to show what I believe are potential causes.

Originally Posted by PA23-250

Only thing I would fix there is garnets do not cleave--hence the extreme slurry-dulling effect you get on a coticule.

I get the same microbevel look on my Jnat too--requires slurry to do anything. If I only go 1-2 rounds, it does look like I used tape on the edge. I always stick to pretty much no pressure on that stone, as it has a way of sucking a blade to the surface.

+1
Yep they do not cleave but they do shatter into
smaller bits with sharp edges. That is why I used
the word "pulverize".