Mechanics of chipbreakers and high cutting angles in woodworking planes. Abstract.

[David Weaver]

Put the breaker in a vise and bend it. They're stamped and unhardened and you can get away with a lot.

[jamie shard]

Adam, please try this. You're the perfect test case. See if you can tune up the chip breaker, set it close, and get no tear out. Almost everyone else has a stake in the argument, your results (with pictures!) would mean a lot.

[David Weaver]

At the same time, anyone else who has "no stake" could weigh in how well they've been able to use a cap iron (vs. not using it). Adam sort of has a negative bias already, but his issue with what is apparently a beat chipbreaker setup is a realistic problem that other people buying used or used up tools may find.

As far as money goes, I have no stake. I've never been paid to write an article or test a tool with or without a cap iron based on the cap iron itself. I've never been paid money to test a tool at all (I have been allowed to keep a few low-value tools, none of them planes and none are on the market).

But I'd welcome input from any of the users out there who just read my article or the article kees wrote and then tried it out. If they found the experiment a failure or otherwise.

[Jim Koepke]

Now if someone could only make a chip breaker for bevel up planes...

jtk

[David Weaver]

I wonder if anyone is ever going to come up with a fine-threaded robust setup that will allow the cap iron to be adjusted on the fly. This is, of course, not something that's necessary, and would be costly to make, but it would be kind of nifty.

Maybe the depth of wear on the leading edge (since the back of the iron wears faster when the cap iron is set close) would create a gap - who knows...I've never seen the depth of that wear stated in thousandths (bet some quick research could be made to figure it out, though).

In kees' article, it's clear to see that the traveling chip is creating wear grooves in the cap iron set and on the 60 degree set, it's easy to see that the chip is deflected early and the wear doesn't travel as far up the iron. In practice, not something to be concerned about (that wear), either, which exemplifies the danger of coming to a conclusion over pictures.

[Kees Heiden]

I wouldn't try to read too much from those pictures. I still find it terribly difficult to get decent pics with that microscope. I was glad that the wearbevel is clear to see.

[David Weaver]

I agree on picture difficulty. A couple of months ago, I took the picture of razor bevels expecting to see natural stones showing almost mark-free edges from the translucent and some of the other natural stones that I have - like these do:

http://www.tzknives.com/razorbevels.html

When i took pictures, I could see pronounced scratches on everything except razor bevels that had been hit with chromium oxide graded powder (strangely, the shaving quality of the edges was very similar, much more so than the pictures would suggest).

Pictures of such small things are a good thing to look at, and then see if you can draw a conclusion in practice. Bad things happen when we look at those pictures and make definitive statements without anything else.

(I think the difference between my microscope at 200x and zowadas is that the orientation of light in my setup facilitated the reflection of the scratches, whereas shallow scratches seem to be exempt in tim's setup.

[Jim Koepke]

Maybe the depth of wear on the leading edge (since the back of the iron wears faster when the cap iron is set close)

Isn't that just the 'lazy man's' way of getting his iron 'ruler tricked'?

jtk

[Kees Heiden]

Mine is 470x. Very difficult to focus too. I think the scrathces you see are from my 8000 stone.
BTW, yu're looking at the bevel side. It is the clearance wear bevel, the wear bevel at the clearance side. The other side has a much longer and shallower wearbevel, which looks very smooth.

[Warren Mickley]

Hang in there Adam. There is a reason that hardly anyone used the double iron five years ago. It takes attention to detail just to get started and lots of experience to know how to use it in individual situations for the best results. For instance, what is the best configuration for planing quarter sawn ash with a mild curl with .003 inch shavings? Even if you've had success with some woods it can be different with others. Derek calls it unreliable and yes, it was unreliable for me when I was a beginner also.

At times some people wanted me to give measurements of settings so they could try it themselves and report back that it did not work. In the past I have compared the double iron to using hot hide glue, pole vaulting, and playing the violin. Each of these activities can be frustrating at the beginning but worthwhile when experience kicks in. So keep at it- well worth the effort.

[David Weaver]

Mine is 470x. Very difficult to focus too. I think the scrathces you see are from my 8000 stone.
BTW, yu're looking at the bevel side. It is the clearance wear bevel, the wear bevel at the clearance side. The other side has a much longer and shallower wearbevel, which looks very smooth.

Ahhh...I wasn't looking at what I thought I was looking at.

[Adam Cruea]

Put the breaker in a vise and bend it. They're stamped and unhardened and you can get away with a lot.

Stupid question. . .do you slightly bow the entire thing or just the end toward the sharp end of the iron?

I should say that while I don't have stake, I'm very in the camp of "chipbreakers stop tearout" because I am able to minimize tear out with older chipbreakers (specifically, my 603 works wonderfully with minimal tearout). It's just that I'd like my old irons and chipbreakers to be like my new LN 4 1/2; only tearing out in the extreme gnarliest of grain.

Hang in there Adam. There is a reason that hardly anyone used the double iron five years ago. It takes attention to detail just to get started and lots of experience to know how to use it in individual situations for the best results. For instance, what is the best configuration for planing quarter sawn ash with a mild curl with .003 inch shavings? Even if you've had success with some woods it can be different with others. Derek calls it unreliable and yes, it was unreliable for me when I was a beginner also.

At times some people wanted me to give measurements of settings so they could try it themselves and report back that it did not work. In the past I have compared the double iron to using hot hide glue, pole vaulting, and playing the violin. Each of these activities can be frustrating at the beginning but worthwhile when experience kicks in. So keep at it- well worth the effort.

Yeah, I understand. While I'm not experienced, I'm smart enough to get the hang of things quickly. I can't dispute the double iron helps with all this as I've torn out with a bevel-up plane just like a bevel-down. The only difference is by moving a chip-breaker closer to the edge, I can tone down tear-out with a double iron whereas bevel-up is just too fickle for me. So, hopefully with a few more years, all this will be second-nature (or close).

I wouldn't call it unreliable at all; you're working with an organic medium that can change and will not be perfect through-and-through. When I made my hickory workbench, I seriously contemplated giving up woodworking because it was extremely tough to do, but I decided my next project would be on a different wood. As you can tell from my history and posting on here, I'm glad I didn't give up. Hickory is just a pain to work. White oak is a pleasure for me, and I'm learning soft maple is absolutely gorgeous. I can't wait until I get to walnut, cherry, and some of the other stuff.

And I definitely get your comparison to playing an instrument. I played bassoon, clarinet, bass guitar, and saxophone. I'm glad I stuck with those even when they were insanely difficult and I regret giving up playing music. It's an indescribable feeling being able to do it.

[David Weaver]

Stupid question. . .do you slightly bow the entire thing or just the end toward the sharp end of the iron?

I should say that while I don't have stake, I'm very in the camp of "chipbreakers stop tearout" because I am able to minimize tear out with older chipbreakers (specifically, my 603 works wonderfully with minimal tearout). It's just that I'd like my old irons and chipbreakers to be like my new LN 4 1/2; only tearing out in the extreme gnarliest of grain.

I have aluminum soft jaws on my bench vise (and I have a large bench vise). I will either take the cap iron hump and put it in the soft jaws and then bend the rest of it hoping that the point that flexes is right behind the hump, or put the flat part of the cap iron in the vise with just the hump sticking out and put a pine block on the hump and hammer it. It only usually has to move a little.

And FWIW, I have gotten cocobolo from time to time between a cap iron and an iron, but in the last couple of cocobolo planes, it didn't occur. When you go to the outer reaches, some of those woods have such strong shavings that they'll get under a cap iron. I wouldn't want to dimension them with a high angle plane, either - it's really a matter of them not being that nice to work by hand in any quantity, other than maybe final smoothing. Hickory and such other things you like to torture yourself with shouldn't be a problem, though -cocobolo is almost twice as hard in the late wood.

[Adam Cruea]

I have aluminum soft jaws on my bench vise (and I have a large bench vise). I will either take the cap iron hump and put it in the soft jaws and then bend the rest of it hoping that the point that flexes is right behind the hump, or put the flat part of the cap iron in the vise with just the hump sticking out and put a pine block on the hump and hammer it. It only usually has to move a little.

And FWIW, I have gotten cocobolo from time to time between a cap iron and an iron, but in the last couple of cocobolo planes, it didn't occur. When you go to the outer reaches, some of those woods have such strong shavings that they'll get under a cap iron. I wouldn't want to dimension them with a high angle plane, either - it's really a matter of them not being that nice to work by hand in any quantity, other than maybe final smoothing. Hickory and such other things you like to torture yourself with shouldn't be a problem, though -cocobolo is almost twice as hard in the late wood.

Awesome! I will definitely do that then and see if it provides any benefit.

And what can I say? I'm a masochist. :P I actually like steep, steep learning curves and having to solve problems.

[Sam Cui]

This?
http://www.ukworkshop.co.uk/forums/g...er-t82202.html