Cap iron set

[Graham Haydon]

This is interesting, however I think I'll expand on a point I think Derek was hinting at. The value of setting a cap iron properly is to get clean surfaces. I think there is most value in posting pictures of a surface that has issues and the shavings produced, then an adjustment, an improved surface and the shavings produced.
Knowing where the sweet spot is, has many things in common with planing square or cutting straight. It just has to be learned.
I do see merit in the detail and information you are presenting, please keep the conversation going! But many old books and tradesman had it right. You set it close. How close? You'll work it out with practice. The biggest lesson with the cap iron was not to dismiss experienced workers who had found success with it. That's not a slight at you, just a human condition of being dismissive of how to get the best out of tools. I'm sure I've done so myself as have others https://blog.lostartpress.com/2007/1...duce-tear-out/

[Brian Holcombe]

I've certainly had boards that misbehaved to the point where a setting that tight along with a light shaving were required. Planing curly cherry recently I was using such a setting for finish planing.

[steven c newman]

Right now, all I'm working with is a bunch of Curly Maple..
lines.jpg
Not really concerned about see-through shavings, either..
end grain bevels.jpg
Would take way too long to make a bunch of bevels....( most of the shavings there on the floor are from doing two bevels, the "noodle"-like shavings are from the Stanley 45
noodles.jpg
Noodles")
dry fit.jpg
Dry fit, needs the last bevel planed..
Stanley #4c.jpg
1mm set back on the chipbreaker. The "other" item in this set up is the lever cap. It helps to stiffen the chipbreaker.

[Patrick Chase]

.003 setback is at 45 degree blade angle so that might limit the shaving to only about .002 maximum shaving thickness. I'm curious though, how much clearance there is in front of the chipbreaker to the front of the mouth with it all set that close. Also, Patrick didn't show a Bailey style chipbreaker, would that make a differrnce?

In practical terms I agree, but... Kato/Kawai took a 4 mil shaving with a 4 mil cap iron setback (~2.8 mil "depth of set" taking bed angle into account), so clearly it's feasible to work with the cap iron extending below the sole of the plane.

The catch is that in their setup the wood was narrower than the iron, so they didn't have to worry about what happens at the edges. In the real world our cap irons are generally so close in width to the iron that they extend a tiny bit past one corner or the other when we set the cap iron by naked eye. That protruding corner will gouge the wood if your cap iron set and shaving thickness are such that the cap iron is below the plane sole.

[Patrick Chase]

I've certainly had boards that misbehaved to the point where a setting that tight along with a light shaving were required. Planing curly cherry recently I was using such a setting for finish planing.

Hah, how did I know you would turn out to be a member of the "aggressive set (when needed) club".

EDIT: I've certainly seen cases where I get shallow tearout with ~2-mil shavings, and moving the cap iron "all the way up" as shown here pretty much kills those dead.

[Patrick Chase]

Answering the second part of Pat's question...

I'm curious though, how much clearance there is in front of the chipbreaker to the front of the mouth with it all set that close. Also, Patrick didn't show a Bailey style chipbreaker, would that make a differrnce?

I use a pretty wide mouth when I'm setting the cap iron close like this. I don't know how wide, but easily > 1 mm.

One thing to note is that the steepest part of the cap iron face is also pretty small here, on the order of half a millimeter. It's just tall enough to break the shaving, and no more. That in turn minimizes its impact on clearance.

IMO a Bailey style cap iron helps by presenting a continuously curved surface to the shaving. The tip of a Bailey-style cap iron is generally around 40 deg (depending on maker), so even if you grind in a 50 deg breaking face as I did here there isn't a terribly sudden transition to the rest of the cap iron. In contrast the iron in the picture goes from 50 to ~25 deg at that first corner, which is non-ideal. As I said it needs to be reprofiled, I just haven't gotten to it yet.

[Jim Koepke]

It is also possible to remove some metal from the top of the front half of the mouth of a Stanle/Bailey style plane without opening the mouth. This will help some with clearance issues.

jtk

[James Pallas]

Interesting thread. I have a few questions for the experts. First I'll say I get the cap iron set up. I experimented and know it works. My question is this. You have a piece of lumber, rough, that looking at the long edge it looks like QS with lots of reversals. You have to start somewhere so you go with a jack Wide open mouth cambered blade and you get major tear out. Do you go straight to your smoother and flatten the whole piece with tiny shavings or just how do you do it. You are going to end up taking a lot of material with tiny shaving at some point. What is your approach?
Jim

[Brian Holcombe]

Hah, how did I know you would turn out to be a member of the "aggressive set (when needed) club".

EDIT: I've certainly seen cases where I get shallow tearout with ~2-mil shavings, and moving the cap iron "all the way up" as shown here pretty much kills those dead.

Absolutely and that is the kind of situation I had in mind.

[Brian Holcombe]

Interesting thread. I have a few questions for the experts. First I'll say I get the cap iron set up. I experimented and know it works. My question is this. You have a piece of lumber, rough, that looking at the long edge it looks like QS with lots of reversals. You have to start somewhere so you go with a jack Wide open mouth cambered blade and you get major tear out. Do you go straight to your smoother and flatten the whole piece with tiny shavings or just how do you do it. You are going to end up taking a lot of material with tiny shaving at some point. What is your approach?
Jim

It depends. I almost never use a jack for prepping stock unless I have a ton of material to take off, which is then considered poor planning on my part. So I use it instead when I have a board that's out of flat by a lot.

I'm normally starting with a try plane to joint the face then smoother.

I've had a few slabs that required me to use a smoother start to finish, they were truly miserable but fairly rare.

[Warren Mickley]

I use a double iron jack plane and a double iron trying plane to prepare stock. In traditional work the smoothing plane is used to clean off finished work. After joinery and such the timber accumulates scuffs, maybe dirt or markings. This is removed just before assembly with the smoothing plane, one or two passes.

[Brian Holcombe]

This one gives me nightmares still, easy enough with a smoother but tore out with literally everything else.

[Patrick Chase]

Interesting thread. I have a few questions for the experts. First I'll say I get the cap iron set up. I experimented and know it works. My question is this. You have a piece of lumber, rough, that looking at the long edge it looks like QS with lots of reversals. You have to start somewhere so you go with a jack Wide open mouth cambered blade and you get major tear out. Do you go straight to your smoother and flatten the whole piece with tiny shavings or just how do you do it. You are going to end up taking a lot of material with tiny shaving at some point. What is your approach?
Jim

Depends. I have a Jack set up with a minimally-cambered blade, and I can (and do) use relatively close cap iron sets with that, the key word being "relative". Obviously I'd take deeper cuts and use a larger cap iron setback than I demonstrated earlier in this thread. I also use relatively tight sets on jointers.

I think the key thing to keep in mind is that at each phase you don't want to leave deeper tearout than the next plane down can easily remove. The Jack shouldn't leave tearout much deeper than the jointer's depth-of-cut, and the jointer shouldn't leave tearout much deeper than the smoother's depth-of-cut. You don't need to completely eliminate tearout until you get to the smoother, and trying to do so will slow you down as it will force you to use finer sets and take shallower cuts early in the process when your main focus should be on getting the right geometry as efficiently as possible.

[Stewie Simpson]

In practical terms I agree, but... Kato/Kawai took a 4 mil shaving with a 4 mil cap iron setback (~2.8 mil "depth of set" taking bed angle into account), so clearly it's feasible to work with the cap iron extending below the sole of the plane.

IMO. Ignore that advise. Same applies to those that advocate a capiron clearance of 0.1mm. You will choke the movement of shaving.

[Patrick Chase]

IMO. Ignore that advise. Same applies to those that advocate a capiron clearance of 0.1mm. You will choke the shaving.

Thanks for the misleading, out-of-context quotation, Stewie.

All, the rest of the post he quoted explained why it's a bad idea to have the cap iron extend below the sole. There's no disagreement here, just certain folks being disagreeable and manufacturing controversy.