Chip breakers and rougher planes

[Jim Koepke]

I was thinking more about getting to the bottom of a deep ‘scar’ of tear out with jointer and smoother.

This is how my thought process looks at a "deep 'scar' of tear out."

How deep is it? Will that much depth have to be taken off of the full surface?

If this 'scar' has much depth, that could be a lot of planing with a jointer and smoother.

A decorative patch/inlay might be easier.

jtk

[Rob Luter]

The "sweet spot" of setting a chip breaker has a relationship with how thick of a shaving is to be taken.

If a smoother is being used to take gossamer, see through shavings, it can be very close to the edge. This will be helpful in the case of tricky or reversing grain.

If the plane is being used as a scrub plane to knock down twist and high spots, the chip breaker should be set to the back of the camber. The problem with this can be with a small radius on the blade's camber, the chip breaker may be back too far to properly use the blade adjuster. Some will modify the chip breaker to work with this. My solution is to use a larger radius.

Attachment 513734

These blades, from left to right are used in a #5, a #5-1/4 & a #40. The #40 of course doesn't use a chip breaker.

For my other bench planes there is very little to no camber used on the blades. A plane taking very thin shavings, 0.0015" or less, tends to not leave noticeable tracks. it is also possible to give an extra stroke or two at the edges of a blade so the edge of the shaving tapers off to nothing.

Here is an old thread on that > https://sawmillcreek.org/showthread.php?158373


jtk

^^ This ^^

[Warren Mickley]

Besides, tear out more than necessary isn’t beneficial. That just means more work at each step along the way. That was part of my reason for asking the question.

Yes, you want less work each step, not more.

We generally don't try to "hog" material when flattening a side. We want to preserve as much material as possible and we want to make a flat surface with as little effort as possible.

I wrote a post on another forum promoting the value of double iron use for roughing planes. That was December 7, 2007.

David Weaver wrote similar posts in 2012 and 2014.

[Charles Edward]

Lordy, it would sure be wonderful if every component of a piece of furniture had a finished thickness of 7/8". Wives, daughters, sisters, and aunts could be brought to bear on that. The reality is that you sometimes have to remove a lot of material, resawing may not be an option, whatever. You need a plan and a procedure for those occasions. You need to remove the material quickly, but without making it look as if it had been carpet-bombed. You won't learn to do this reading about it, you'll only learn by doing the work at the bench.

[Ben Ellenberger]

I had to get out the calipers today and measure some shavings because this thread made me curious. I had about a 1/4” to take off this piece of hard maple. I measured the shavings at a strong 3/128”. So, I’d guess my chipbreaker is set back from the middle of the blade by a strong 1/32”. Because of the camber on the blade the corners of the chipbreaker and the blade are almost even (I haven’t bothered putting a camber on the chipbreaker). Because of reversing grain I needed to change directions in the middle of the board. I still got tear out, so switched to a finer-set plane sooner than I would have if the grain was more favorable. It all seemed to work out OK in the end. These will be octagonal legs, so more material is getting removed before everything is done.

IMG_2231.jpg

[Rafael Herrera]

The chipbreaker can be moved forward a bit more, still taking the same shaving thicknes. The cb corners and the iron corners don't have to be aligned, you're not taking full width shavings, aren't you?

Test to see if tear out is mitigated or eliminated.