Thanks for your thougths.
I read the article on your site a while ago and also about hollow
grinding in Leonard Lee's book. Both are about chisle sharpening and
have created the myth that hollow shapes are less supportive in all
cases. The conclusions cannot be easily translated to bevel down
Two methods that require work on the entire bevel to sharpen are a
single bevel and hollow _honing_
which is like the Tormek system. For a
given included angle the hollow honed shape wins hands down. It has a
lower contact height on the frog.
Two methods that require work on less metal when re sharpening are the
double bevel (primary/microbevel) and hollow grinding followed by flat
honing (as described by Krenov). They have the same geometry at the
tip. They can both have the same support angle because you can choose
the primary bevel angle or the grinding wheel diameter. But the hollow
ground/flat honed method leaves more metal behind the blade and has a
lower contact height. So the hollow shape wins this comparison too!
But both comparisons are based on geometry and after that available
equipment and the time necessary to make a quality cutting edge must be
How well does a blade with 12 1/2 degree primary perform in difficult
I wasn't concerned with skitter in my statement but your article is
interesting and I'll have to think more about the chatter issue. If the
chatter is occuring in the very tip then it doesn't matter how thick
the blade is. If the chatter is due to the length of the blade flexing
and your plane is holding the blade the best it can then it does matter
how thick the blade is. You measured the frequency of the resulting
sound which is interesting. What we really need to know is the
wavelength in the blade to determine where the chatter occurs. We could
ask for some experience...
Has anyone ever remedied chatter by buying a thicker blade? But the two
blades were probably different metals with different rigidities.
Thanks again. Your comments will help me word my thoughts more