# Hand Planes & The research of Doctor Norman C Franz



## Calzone (May 15, 2012)

I have been dabbling in hand planes a lot recently. probably too much for my own good, but as of now I have a block plane, a Stanley No.7 Joiner plane, a Groz Smoothing plane, but none of these serve my purpose at the moment, and I'm thinking about making a custom one.

After doing research on hand planes and against the grain cutting, I found a scientist by the name of Dr. Norman C. Franz. He made a custom joiner and did heavy research on how going against the grain forms different classifications of chips. Little did he know, soon after his thesis all of his research would apply to the field of hand planes and any form of a blade used for cutting wood in a slicing manner. When I say he did research, I mean he had a high speed camera microscope documenting everything. Some very cool pictures accompanied his original article. There is a wikipedia page on the research, and you can either read it right here or follow this link: http://en.wikipedia.org/wiki/Chip_formation



> *Type I chip*
> I think We've all seen this surface after a joiner before. A zoomed in view of a Type 1 Chip in the process shows that the wood is being lifted up by the heavier angle of the plane and isn't even being cut, rather pulled before it snaps a little ways down.
> 
> 
> ...


I just thought you all might like to read up a little bit on blades and their adverse effects on wood!


----------



## firemedic (Dec 26, 2010)

That's good stuff. In regards to plane irons, Professor Yasunori Kawai took it quite a bit further with studying the effects of the chip breaker at various angles of iron and chip breaker as well as the way it's set.

You can see the translated video here:
http://vimeo.com/41372857

It's definitely worth a look if the above caught ya fancy.


----------



## firemedic (Dec 26, 2010)

I have to disagree with the proposition of a scraper producing a type III chip (as he classifies them). Were he not using a burnished scraper this would be the case.

A properly burnished scraper has a "bur" that is very sharp and contacts the wood at a low angle. Unfortunately most "modern" wood workers, be it out of ignorance or laziness, do not properly prepare a scraper.


----------



## timetestedtools (Aug 23, 2012)

After reading some similar work, I did my own little test. http://lumberjocks.com/donwilwol/blog/30376
The problem with some of this work is its taken to literal. Everything affects how a plane works, the type of wood, is the chip breaker polished, is there a chip breaker, whats the angle of a chip breaker, what the sharpened angle, how the user is holding the plane, how much pressure the user puts on the plane, how wide is the mouth, how wide is the mouth in relationship to the chip breaker, and it goes on and on.

And its been said "Sharp fixes everything". There is a point were sharp and sharper are the same, but you need to get to that point.

In reality, its good to understand how the physics works, but you need to expirience it for yourself and how it relates to what you do.

Thats just my 2 cents worth.


----------



## firemedic (Dec 26, 2010)

Good read there. It's a rabbet hole, isn't it :laughing:


----------

