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View Full Version : Bevel angle, Japanese chisels...



ian maybury
07-21-2014, 8:52 AM
Just wondering what the thinking on a single bevel sharpening angle strategy for Japanese white steel chisels is these days - reading throws up a million views ranging from about 25 - to 35 deg. Hollow grinding (not me) may change the picture a bit for some too.

The issue arises now that the sharpening set up is dialled in (the Veritas Mk 2 thread) - it's time to sort out the rest of the set. ( Matsumuras from Dieter Schmid in Germany - hope they are OK - some of each type: http://www.fine-tools.com/matsumura.html , and http://www.fine-tools.com/zinkenstemmeisen.html ) So far I've been sharpening a few ad-hoc to 30 deg single bevel and had no issues in use, but it's not been very demanding work. They look mostly like being used on oak and walnut - mixed chopping (some) and paring. I'm easy on tools. The plan is to buy a few long handled paring chisels in due course, and to sharpen them at a lower bevel angle for exclusively hand use.

All being equal i'm tempted to set all of the current chisels up at 30deg, and go 25 deg or a bit less with the paring chisels in due course. My impression is that it's not a particularly critical factor anyway unless problems arise in the context of a specific job - but my experience is fairly limited and I don't want to end up with edges chipping all over the place...

Derek Cohen
07-21-2014, 11:25 AM
Hi Ian

30 degrees for all bench and dovetail chisels (since they are designed to be hit with a gennou), and 25 degrees for all slicks (paring chisels) since they will be pushed.

Regards from Perth

Derek

Terry Beadle
07-21-2014, 11:29 AM
I don't hollow grind my japanese chisels either. I've kept them at 30 degrees except for one wide chisel I use as a bench scraper and that on is at 25. I use water stones and find keeping the japanese chisels sharp no problem. I have the paring chisel set from Narex ( http://www.leevalley.com/us/wood/page.aspx?p=71290&cat=1,41504 ) and they are set at a little less than 25 but more than 22. I also put a secondary bevel on one or two of the set of 5 when I experienced a rolling of the cutting edge in particularly hard parts of SYP. I must say I've found the paring chisels more handy than I expected.

I do have one or two that are set at 25 and not 30 that are not used for paring but are used in softish hardwoods.

I've a 5/8ths Blue Spruce that I've kept stock and it works great. It's a non-cryo A2 and I use a diamond paddle to set the initial cutting edge and then go to the water stones and lastly the green polishing compound on rock maple strop. My 1/2 in japanese chisel is set at 23 degrees and keeps it's edge very well. It's out of sword steel and is expensive, however, it's the "go to" chisel when all else fails.

I agree with your thinking about setting up your bench chisels at 30 but I also think one or two at 25 is a nice option depending on the grain density of the work piece or if a knot is involved.

I also put a micro bevel on any chisel that's at 25 or 30 and having an edge fail problem. I go to a 33 ~ 35 micro bevel in that case. The mortising chisels are set to 30 and have a 35 micro bevel as my standard set up. My Ashley Isles were at 25 with 30 micro bevels and had some edge rolling issues so I boosted them to 30 with 35 micro's.

I've not had any problems with cherry oak, walnut, or pine ( except in a knotty situation ). Cocobolo required 37. Purple Heart is ok with 35 but leans to needing a bit more.

Just my thoughts. The Irish are a tough people so you will whip it into shape!

Good luck and enjoy the shavings!

ian maybury
07-21-2014, 2:01 PM
Thank you very much guys - solid information and it all fits with my framework. 30 deg it is pending the parers. Guess the trick is not to shade it too close to the wind by reducing the bevel too much - so that it's only in exceptional circumstances that chipping may occur. With a microbevel available as a fall back in those cases. Think I will try to keep both sets of chisels at 30 deg (i know bloody well that the ones i chose for a flat bevel would be the very ones that i'd end up needing at the steeper angle on the next job), but will sharpen a couple of strays flat as you suggest.
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We moan a bit here Terry, but i guess in the end living in a small country with a population about the size of a medium city (about 3m) there's not all that much that comes easy...