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Ken Cohen
02-02-2010, 9:02 PM
Hi--

I'm attending a woodworking class which teaches hollow grinding on bevel down (Stanley) planes. I was the lucky Xmas gift recipient of a new Veritas BUJ plane which I want to inaugurate in the class.

Two questions:

Can you use traditional hollow grinding techniques to hone the blade?

What about cambering (which is part of the course)? Google led me to this long article on the subject:

http://www.inthewoodshop.com/WoodworkTechniques/TheSecretToCamberinBUPlaneBlades.html

Course teacher is an absolute pro, but he's never done a BU blade. Is this straightforward, or should I be concerned?

Thanks for the help.

Ken

David Gendron
02-02-2010, 9:17 PM
you don't have to be concern, neither is he. You can of course hollow grind a BU iron and you can also grind a camber to it. I Chris Shwarz wrote about that in one of his blog post, and basicly, because of the BU nature you will have to exagerate the camber to make it as efficient! I will try to get back to it later with the link to his post!

Ken Cohen
02-02-2010, 9:53 PM
Thanks for the helpful and prompt response.

I searched for the Chris Schwarz blog post and couldn't find it -- so I would appreciate the link.

Jim Koepke
02-02-2010, 10:36 PM
Derek Cohen also has something about cambering bevel up blades on his web site. It is a fountain of knowledge.

http://www.inthewoodshop.com/

See you in a few days.:D

jim

David Gendron
02-02-2010, 10:49 PM
There it is;
http://blog.woodworking-magazine.com/blog/Camber+With+A+Honing+Guide.aspx
and if you have his book, Handplane Esentials, it is on page 122.
Ithink the cambering of plane iron is a lot of trials and errors, but that should give you a good starting point!
good luck!

Derek Cohen
02-03-2010, 12:55 AM
Hi--

I'm attending a woodworking class which teaches hollow grinding on bevel down (Stanley) planes. I was the lucky Xmas gift recipient of a new Veritas BUJ plane which I want to inaugurate in the class.

Two questions:

Can you use traditional hollow grinding techniques to hone the blade?

What about cambering (which is part of the course)? Google led me to this long article on the subject:

http://www.inthewoodshop.com/WoodworkTechniques/TheSecretToCamberinBUPlaneBlades.html

Course teacher is an absolute pro, but he's never done a BU blade. Is this straightforward, or should I be concerned?

Thanks for the help.

Ken

Hi Ken

I hollow grind all my blades these days (rather than using a belt sander), including the BU blades. I then move on to freehanding with BD blades, while BU blades generally still need a honing guide when the secondary bevel is greater than 35 degrees. I'd say that 35 degrees is the highest you would want to go for the primary bevel if you plan to camber a BU blade directly on the hollow grind. Aim for 25 degrees, then add the remainder on a honing guide. That is what I do (with the one exception of a BU smoother that has a 25 degree bed).

You will note that the blog of Chris Schwarz on cambering (BD) is the same as the method I offer in my article on BU blades (posted a year earlier). I call it "Cambering by the Numbers" and, while there are modifications by myself, I attribute it to David Charlesworth.

Regards from Perth

Derek

David Gendron
02-03-2010, 3:22 AM
Thank you Derek, that is a great article, and way better explaned than any other one I've seen!
Thank you!

Paul Murphy
02-04-2010, 12:11 AM
I would also like to thank Derek for explaining camber on a bevel up blade. It comes at the right time for me as I have a new Veritas low angle smoother, and would like to try the various higher cutting angles.

I wonder if Veritas will come out with additional camber roller attachments for their sharpening jig? Might be handy for folks like me who are new to all of this.