Cap iron setting

[Nicholas Lawrence]

I have read a number of times over the years about the virtues of setting the cap iron molecularly close to the cutting edge of the plane iron, and there are lots of videos and articles out there showing impressive results. When I try to do that however, I encounter one of two problems:

-As you advance the cap iron plus plane iron into the thorat of the plaint, the combination is too thick for the throat of the plane, and even very thin shavings jam,

-The cap iron is not long enough, and the locking screw does not have room to traverse in the recess in the frog, so the iron cannot be advanced far enough to get into the throat and take shaving.

Has anyone else had these issues? I have a motley collection of Stanley users, but I have now tried the close setting on all three with the above results, and am wondering what I am missing.

The good news is I get pretty good results with "normal settings", but in light of everything I read I am curious about the results I might see with the "close" settings.

[Robert Engel]

How far do you want the blade protruding?
I don't know exactly what you're doing but the blade only has to protrude a thou or two beyond the mouth, so the cap iron should never be hindering.

I keep mine about 1/32 behind the blade.

Have you tried adjusting the frog back a little? This solves the narrow mouth issue.

If you are using a Stanley cap iron there shouldn't be a problem.

Others more knowledgeable than me will chime in, I'm sure.

[Mike Cherry]

It is my understanding that if you get things right between the blade and cap iron, you can essentially ignore the mouth setting. Normally a tight mouth helps keep the fibers in place longer. This gives the blade time to cut them before they tear. The close chip breaker breaks the chip sooner preventing tearing. This is at least how I understand it.

[Brian Holcombe]

Nicholas,

It depends....

On a #4 plane set for smoothing I have the cap iron very close. On a Jack, #7 plane or a try plane I have the cap iron settings close enough to minimize tearout but not so close that I'm jamming shavings. The reason is two-fold, the thickness of the shavings being the primary. One a Jack, a 7 or a try plane I'm taking heavier cuts, the heaviest being with the jack plane, the try plane being about a .005" shaving and the #7 about a .002-3" shaving.

On the smoother plane I'm taking .001"~ or lighter and set the cap iron where I get straight or rolling shavings (straight are more ideal). If the cap iron is set so closely that the shavings wrinkle up then I back it off just a hair.

There is no one-size fits all for these things, so thats why most people will offer a range. I dont measure my settings any longer, I just set by eye and go by the chip feedback. The wood you're planing has effect on it, the grain you're planing has effect, ect, ect. To give you an idea, most of the time for a finish plane the setting is likely right in the range of .010" or closer, for my other planes it's probably more like double or triple of that.

Your planes should be able to accommodate the proper chip breaker settings, if they cannot it begs the question of the length of the chipbreaker, is it original to the plane? Stanley experts will know more about this than I will, but I've only modified one of my planes (LN not stanley) due to my settings vs the manufactures intended range of settings.

When you say the shavings are jamming up in the throat I suspect this could actually be a faulty mating between the chip breaker and the back of the plane iron. If there are shavings stuck between the two surfaces when it jams then you have your answer. If you would like a double check use a piece of paper. Paper is about .003", place it between the iron and the cap at different spots along the mating surface, if you can pull the paper out then the mating surfaces need work.

[Kees Heiden]

Do you have the original Stanley capiron in an original Stanley plane with the original blade? I haven't yet seen one that has the problems with adjusting deep enough like you describe. And all my Stanleys, both the very old and the very new have enough room in the mouth when the frog is pulled back.

So I am curious what you have there. Any pictures perhaps?

[Steve Voigt]

As others have mentioned, moving the frog back should solve the clogging problem.

I can't imagine why shouldn't be able to adjust the cut deep enough. You ought to be able to set the blade 1/8 below the sole--not that you'd ever need to, but it should be possible. I wonder if the mouth is not the culprit--if it's too small, and you are using an original Stanley cap iron, maybe the hump is bottoming out on the forward part of the mouth.

As an aside re earlier posts, 1/32 is not close enough to get much of a chipbreaker effect, except in very heavy cuts. For most situations, the effective range is more like .004-.020. Of course, it can be set back further than that, because the majority of planing situations don't really require a super-close setting--you only need it if the grain is reversing, curling, etc. you should also be able to take thicker shavings than one or two thou; with the CB set correctly, tearout-free shavings of .005 or more are not a problem.

[Stewie Simpson]

Hi Kees. I have heard it said that Stanley was well aware of the importance of a closely set capiron to combat tear out with their bench planes, but I have some major doubts Stanley ever sold any of its metal planes off the shelf preset with the frog pushed back and a closely set CB. The same comment would apply to other well established brands of metal planes using the same design pattern, such as Record Planes.

Stewie;

[Stewie Simpson]

David Weavers comment on another forum seems to make plenty of sense.

the cap iron set should be slightly larger than the thickest shaving you'll take with a given set.

Stewie;

[Kees Heiden]

I have no idea how Stanley or Record sold their planes. I wasn't around to look at them! But that doesn't change my experience that every Stanley or Record I have had in my hands were capable of being setup like Steve describes above. And those were planes from around 1900, from the 1930-ies and post war UK made planes, so, quite a range, The old ones certainly have a much tighter mouth then the newer ones, but with the frog set back it is no problem to create a 0.6 - 0.8 mm wide mouth. Plenty enough for a smoother.

There is a little snippet about the setup of a capiron in one of Stanleys booklets.

stanley.jpg

[steven c newman]

Sounds like it is merely the wrong cap iron. Find the OEM one for that plane, tune it to mate with the iron.

Thicker irons and chipbreaker/cap irons are not always the answer to chatter problems.....tuning the plane up the correct ways usually is the best.

Close settings? The only close settings needed is right at the end of the iron and chip breaker. 1/16" to 1/64" between the ends of the two will work nicely. Too tight a mouth merely clogs up with shavings, one needs the room for them to escape out the top. A SHARP iron, a "No-gap" cap iron, set close to the edge work quite nicely. Has for 100+ years now...

[Steve Voigt]

I'm referring to routine situations and I'm guessing about 1/32 could be between 1/64 and 1/32 it doesn't matter that much IME.
I would guess somewhere in the .020-.025 range. On nicely grained wood, I routinely get .001 thick shavings and very nice surfaces.
I have tried setting the chip breaker much closer on my smoother and haven't seen the difference.
Regardless, in my experience this is fine for 90% of the planing I need to do.

I do agree with the posters recommendation, when difficult grain situations arise.
I go much closer and narrow the mouth down -- before I resort to scraping, that is .

I can't envision setting a cap iron .004 back if the edges on the blade are eased or blade cambered, so what about this case?

Robert,

If you are taking .001 shavings in "nicely-grained wood," there is no need for a close-set chipbreaker. With a sharp blade, you will likely not get tearout, and close-set chipbreaker won't improve a surface that is already tearout-free. That's why you're not seeing any difference. You could move the chipbreaker back to 3/32" and it wouldn't matter; conversely, you could move it forward and still see no difference, until you moved it too close and it started to degrade the surface.

The close-set chipbreaker matters when you are (1) planing difficult, e.g. curly or reversing grain; or (2) taking heavier shavings. If you are doing either of these things and getting tearout, then you will need to move the CB closer than 1/32" to solve the problem. However, it is completely unnecessary to close the mouth down. Do it if you want, but it is a less effective strategy than setting the CB close. If the CB alone doesn't do it, then there is a problem somewhere--either it's not set close enough, or maybe you are using an after-market CB with an insufficiently steep bevel on the front.

Regarding your last question, it is rarely necessary to use a setting as close as .004, but once in a while you need to. On a smoothing plane, the camber will certainly be less than .004, so it is not a problem to set the CB right at the edge in the corners. If you have a try plane iron with slightly more camber, the corners of the CB can even slightly overhang the iron, so long as the depth of cut is set so that the CB is not below the sole. I slightly round the corners of my CBs, not as much as one might round the corners of a cutting iron, but just enough to break the sharp corner, and this also helps with super-close settings. There is also nothing wrong with having a slight--like a couple thou--camber on the CB itself. (Just don't try to match the CB camber to the blade camber; I argued about that a long time ago with Dave Weaver, he was right, I was wrong.)

Anyway, I'm not trying to be disagreeable; I made the comment because the OP referred to a "molecularly close" setting and your comment right after referred to 1/32"…the juxtaposition seemed to imply that 1/32" was close enough and I just wanted to be clear that that isn't always the case.

[Jim Koepke]

-As you advance the cap iron plus plane iron into the thorat of the plaint, the combination is too thick for the throat of the plane, and even very thin shavings jam,

-The cap iron is not long enough, and the locking screw does not have room to traverse in the recess in the frog, so the iron cannot be advanced far enough to get into the throat and take shaving.

Has anyone else had these issues? I have a motley collection of Stanley users, but I have now tried the close setting on all three with the above results, and am wondering what I am missing.

Some very good answers above. From the last part of what is quoted, having all Stanley planes makes this a bit easier to address.

Parts often got switched around on planes. You may have a cap iron(s) from a maker other than Stanley. The cap irons may have been modified by a previous owner. I have a few cap irons picked up in odd lots that do not fit any of my Stanley/Bailey planes. Many have mentioned problems with some after market blades and cap irons not allowing for good adjustment. Not all makers have agreed on the usefulness of a the cap iron/chip breaker setting in avoiding tear out.

There is a chart of chip breaker/cap iron measurements in .pdf available here:

http://www.sawmillcreek.org/showthre...83#post1107683

That may be a good place to start in verifying you have the correct chip breaker/cap iron for your planes. A few posts down is some information on mouth measurements.

If you are going to use the chip breaker to regulate your shavings it is my suggestion you start with the frog set to the back of the mouth. On some of the earlier types of Stanley/Bailey planes the mouths came tight from the factory, as mentioned above. It may be necessary to remove just a hair of metal from the mouth. I have a type 4 - #6 plane that is like this. Any shaving over about 0.004" is too heavy even with the frog all the way back. The mouth on the same plane in a type 9 is also a bit tight with a Hock blade.

One of my planes recently had a similar problem. The shavings appeared to be jamming at the throat when they were actually getting caught under the chip breaker - blade junction and backing up into the throat. A bit of time honing the edge and adjusting the flatness of the chip breaker corrected this.

As Brian said, wrinkled shavings indicate the cap iron is set too close to the edge. They may also look wrinkled if the shaving is catching a burr on the leading edge of the chip breaker.

Brian also mentioned using a piece of paper to check the cap iron's mating to the back of your blade. A piece of paper can also help to indicate if your mouth is overly tight. A thin strip fed in from the underside may also help see where the shavings are catching.

It is also important to remember your blade needs to be sharp and some adjustments may be necessary before this all clicks into place.

Good luck and let is know how this turns out.

jtk

[Nicholas Lawrence]

I appreciate all of the thoughtful replies.

By "close setting" I am indeed talking about setting the cap iron extremely close to the cutting edge of the iron. I have a block plane with an adjustable mouth, and when I experimented with that it never seemed to make much of a difference, so I have concerned myself with getting the mouth opening smaller on the bench planes.

Kees, I do not have pictures at the moment, will try to get a couple that might be helpful when I get home from work. I have never spent a lot of time trying to date what I have, but I think I have an older No. 7 (judging by the keyhole shaped slot in the lever cap) a probably post WWII era No. 5 (judging by kidney shaped hole in lever cap, and orange paint) and a WWII era No. 3 (plastic adjusting knob, plus I believe my grandfather bought it when he came home from France).

The irons I am using now are brand new Veritas replacements with the matching cap irons. I had the same problems with the Stanleys originals though, so I am not sure it is caused by the little bit of difference in the thicknesses. I am not having shavings jam between the cap iron and iron. I have not tried the paper test on them, but those surfaces are pretty tight. The jamming is between the cap iron and the throat.

Here is a sketch of how I set the frogs: Looking from the side, black is the frog, blue is the back side of the throat, green is the front of the throat, and red is the iron/cap iron. Apologies in advance for my artistic abilities, but I hope it helps make clear how I have them set. Other than getting the frog square in the casting, I focused on getting the front of the frog dead even with the back of the throat (I read or imagined that might help reduce chatter by supporting the entire blade). Do folks set them further back than that? They are not projecting into the throat at all the way I have them set now.

image.jpg



Nick

Edited because I forgot to attach the sketch.

[Jim Koepke]

Do folks set them further back than that?

Some may, but for me it is a problem being caused rather than corrected.

jtk

[Kees Heiden]

That's where I set my frog too (on the post WW-I stuff, before everything is different). It's a pitty you are so far away, otherwise it would be easier to help. You use the LV capirons I read. Give it another try with the Stanleys and see where it ends up. The LV blades are quite thin I seem to remember, so that shouldn't change much. But measure them nonetheless. Somewhere around 2mm thick is reasonable.

Have also a look at the angle at the front of the capiron. If it is much more then 45 - 50 degrees, it ends up in the way of the shaving aperture. If there is enough room, then it is no problem, but if it is tight then it certainly doesn't help.

And have a look at that link from Jim Koepke and see if that is helpfull.