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I thought I'd look for a more economical way to deal with some very nice curly cherry I am
working with. Having little experiece hand planing curly cherry, I have been climbing a steep learning curve.
Very sharp iron: check
Chip breaker within a gnats eyebrow of the edge: check
Wax sole: check
Dampen wood: check
Then, it ocurred to me to do more research, which let me to the back-bevel solution. I started out with a 50° degree frog, and added a 7.5° back-bevel:
who needs a stinkin overstuffed coffin smoother! This is truly a revelation (and one that requires no additional $$$.
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Interesting that a back bevel got you those results when a close-set chipbreaker didn't. But good on ya!
Anything worth doing is worth learning how to do better, forever.
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I do wonder where the point of diminishing returns is regarding the angle of the back-bevel?
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Location: Vancouver Island, B.C. -eh!
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Location: Perth, Australia
Phillip, I am not sure why the closed up chipbreaker did not work, unless it was not set up correctly (did you increase the leading edge of the chipbreaker to 50 degrees?).
Yes, high cutting angles work well. My preference is not to use these on wide smoothers with a high centre of effort, such as a 4 1/2 - they become hard work to push. The chipbreaker is a better choice for such planes. Narrower planes , such as a #3 or #4, can better manage a high cutting angle. What were you using?
Regards from Perth
Derek
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Derek:
This is a 4 1/2 with a 50° frog. There is no question that it takes some effort to move this across the board (as compared to a 4 with a 45° frog), but
the level of effort did not increase noticably when I went from no back-bevel to the 7.5° back-bevel. As long as I keep the shavings in the .001" range, its work, but manageable. I have the chip breaker set somewhere between a 1/32 and 1/64 of an inch. I have not fettled the chip breaker: its as it came from LN. I will take a look at that and see if I can sweeten that up a bit. Overall, I have to say
I'm amazed at the effect of the back-bevel. I think I will be stocking up with some more curly cherry at the very next opportunity.
Phil
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I may be off base here but 1/64" = 0.396875 mm. To use the chipbreaker successfully for tearout control, it wants to be at ~ .04 mm and you need a 50° at the leading edge.
Thanks, Curt
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"Life can only be understood backwards; but it must be lived forwards."
-- Soren Kierkegaard
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10-29-2016, 09:54 PM
(This post was last modified: 10-29-2016, 10:12 PM by Philip1231.)
I will try setting the CB using this feeler gauge approach and see what happens:
Chipbreaker-setting Trick: PWW
And what i will be trying on the leading edge of the chipbreaker:
Schwartz on Chipbreaker Setup
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Hi Curt and Philip
0.3 -0.4mm is roughly where I set the chipbreaker. What would make a big difference is the leading edge of the chipbreaker is about 50 degrees. The LN chipbreaker, out of the box, is 25 degrees. This is too low to make a difference.
A 50 degree frog plus 7.5 degree backbevel = 57.5 degree cutting angle. That should work pretty well. I am used to using 60-62 degrees in my high angled smoothers. However the downside of such planes is that one cannot take a thick shaving with the wide planes, such as a #4 1/2. Planing away deep tearout is inefficient. A narrower high angle plane would take a thicker shaving (although not as thick as a a chipbreakered plane).
Regards from Perth
Derek
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10-30-2016, 01:04 PM
(This post was last modified: 10-30-2016, 01:06 PM by hbmcc.)
(10-29-2016, 12:04 PM)Philip1231 Wrote: I do wonder where the point of diminishing returns is regarding the angle of the back-bevel?
Your shoulders and back will tell you when the PODR is exceeded. On any of the points of improvement, not just bevels. If you are a bulldog, like Derek, and live for physical abuse
working on iron camouflaged as wood, the wood surface will no longer feel as good as glass. I stick to the easier side of pain, myself.