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bugbear

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Following on...

Since few woodworkers (except weird ones :D ) have rules scaled down to 1/64",
and you can't even put calipers on a cap-iron setting, I present a visual aid
of what a 1/64" gap looks like on a #4 Bailey, 2 inch iron.

This drawing was made by counting pixels, and should be viewed full size (just click).

EDIT; the drawing shows the proportion of the cap-iron-gap relative to the iron, not the absolute size. A normal
display is high enough resolution for absolute size to work accurately.

cap2_64.png


Adjusting a cap-iron to these sort of dimensions is quite fiddly, and
there is a small risk (which DC noted in passing) of running the cap-iron
over your nice sharp edge, spoiling it.

The article on Woodcentral

BugBear
 

Attachments

  • cap2_64.png
    cap2_64.png
    31.8 KB
One thing that can make cap-iron setting frustrating is the cap-iron moving on the cutting iron as the screw is tightened. That's sometimes down to a tiny burr on the underside of the screw-head. A gentle wipe with a fine file helps, as does seeing that the cap-iron surface is nice and smooth where the screw-head seats. A tiny smear of oil doesn't go amiss, either.

Getting the cap-iron very close isn't easy, but one way is to set the two irons roughly, do the screw up finger-tight, then tap the cap-iron at the top until the setting is what you need. Then nip up the screw. Tapping the top of the cap-iron isn't the easiest since many of them are thinned, but the tip of a screwdriver slid along the cutting iron usually works. Not kind to the screwdriver, but needs must sometimes....
 
mseries":ux9flwwy said:
doesn't your pixel size depend on your resolution and screen size ? That image looks larger than 2" to me

It does, but then a 2" iron looks bigger or smaller depending on how far from your eye it is.

My intention was to show the proportion of the cap-iron gap to the width of the iron, and I believe
in this respect the diagram is accurate.

If I'd aimed for "real size", a 72 DPI screen would have the cap-iron gap as a single 1/72" pixel, the nearest that could be done.

BugBear
 
I'll add a couple of thoughts.

1/64th is definitely something difficult to shoot for on the nose. What you want is to do what Chappie said and that is to light finger tighten the cap iron to the iron, and then proceed to slowly push the cap toward the edge of the iron. When you're new at it you might set it and tap it a fair amount as he suggests.

It's better to not think about distances other than whether or not something looks right. You can see a few thousandths of iron pretty easily if you have a reflective surface and a curved chipbreaker (the differences is stark, even if the curved chipbreaker is bright metal). If you have a fresh metal new chipbreaker with a polished bevel, it's a little harder to see the transition from chipbreaker to iron, and it's helpful to gun blue the cap iron or do something that's semi permanent.

Anyway, you can see the reflection of the iron all the way until you've pushed the cap iron to the very edge. There will be visual cues that become extremely familiar with a few repetitions and you should have no trouble after a couple of weeks in thinking "that just looks right".

I think those things are why old hats have trouble describing how to set the cap iron to newbies.

If you have an iron that still moves after finger tightening when you do final tightening of the cap, that's a pain, but there's usually a metal burr somewhere to explain what's causing that and you can get rid of it. Older cap irons on woodies tend to have a lot more variation in their personalities, but still, you get used to how they behave, and if there's a problem, you can file or sand it off (a burr on the bottom of a cap iron screw, for example, will push the iron and cap iron in different directions.

Anything that seems fiddly at first goes away pretty quickly. It's like riding a bike. Seems like a million things to keep track of at first, but then it's just reflexive and should take about 15 seconds to set.

I can't think of any real practical limitation at this point, but from the perspective of an instructor, if 30% of students in a class are just duds, then it may be difficult to teach it collectively.

I can only cite personal experience. I forced myself (after being goaded by warren) to learn to use the cap iron by barring myself from using anything else on a project that took two weeks and involved a lot of diemensioning and final smoothing. Within a few days, it was clear that a stanley 4 was far better at the finish work (speed wise) than a very precise infill I'd made, because it could work from the try plane prep a lot faster, and within a week it was easy to set the cap iron right about where I wanted to from just looking at it and not thinking about anything other than whether or not it worked right. By the end of two weeks, I took all of my other planes out of the shop and put them in a dry area for storage, which is where they still are.

I overran the edge a couple of times the first few days. Those things go away pretty quickly.

(when I set a cap for a 4 or so thousandth max shaving, which is a really nice way to set a stanley plane, the reflection of the iron is visually about half of the red proportion that's shown in that picture)
 
bugbear":1vkclaay said:
This drawing was made by counting pixels, and should be viewed full size (just click).
Misleading wording, clicked image on my system results in a red line in excess of 1/16" wide.

Even the attachment image is 100+mm wide before clicking on my screen.

The red line may be correct scale for adjusted image size but display resolution variations mean the above statement needs amending.
 
Thanks for this BugBear, I was thinking of starting a thread like this if none of the regulars got around to it.

bugbear":dp3pzu55 said:
My intention was to show the proportion of the cap-iron gap to the width of the iron...
Dead on.

D_W":dp3pzu55 said:
I think those things are why old hats have trouble describing how to set the cap iron to newbies.
A common problem IME. This is one reason to not automatically take as gospel what an experienced or highly-respected woodworker is saying when telling how to do something, they know what they mean but sometimes they are inadvertently giving a false impression. This is not a condemnation, they're not professional communicators after all, and especially when writing word choice can be well meaning but misleading, or at least have some likelihood of being misunderstood.

To bring this into the realm of the cap iron specifically, I've read descriptions with accompanying photos where it's clear the writer's view of "very close" or "extremely close" are nowhere near how I would define them. And "backed off a bit" can be so far away as to make the presence of the cap iron irrelevant (e.g. about 3mm, 1/8").

Which I think highlights the importance of a visual aid such as in the opening post, hard to misinterpret.
 
ED65":3ggc3xxb said:
D_W":3ggc3xxb said:
I think those things are why old hats have trouble describing how to set the cap iron to newbies.

Describing is the key difficulty here - showing would be (and probably was, in the master/apprentice days) easy.

I really liked the distinction between "close" and "kato-close" in the other thread. :D

BugBear
 
bugbear":37xnxeox said:
ED65":37xnxeox said:
D_W":37xnxeox said:
I think those things are why old hats have trouble describing how to set the cap iron to newbies.

Describing is the key difficulty here - showing would be (and probably was, in the master/apprentice days) easy.

I really liked the distinction between "close" and "kato-close" in the other thread. :D

BugBear

I think your red line describe exactly where people should be looking, and does so well. They will just need to make sure they have a light source so they can see the flat part of the iron, distinguish it and then use the advice presented in other threads to determine what looks right. It sounds more complicated than it is, but certainly the way to complicate things entirely is to start thinking of things in thousandths. We can see a few thousandths easily. As soon as we start to try to figure out what's 8 thousandths vs. 6 by eye or with measuring gadgets, all is lost and we've departed what's really useful about our sense and judgement, and ability to differentiate subtleties without attaching units to them.

(the prior advice is to set it closer if there's tearout, and less close if there's jamming or too much resistance - not much to it other than that)
 
Finger tight. followed by abuse of a large old screwdriver, works well for me.

The side of the flat "shaft" makes a good impromptu hammer.

The light source seems to matter. Fluorescent not so good, but daylight in a doorway for instance better.

David
 
Perhaps there's a way to reduce the labour of repeatedly setting the cap-iron distance to close tolerances;

Patent 362743 might now be seen in a new light.

BugBear (cryptic)
 
bugbear":3cq7nwe3 said:
Perhaps there's a way to reduce the labour of repeatedly setting the cap-iron distance to close tolerances;

Patent 362743 might now be seen in a new light.

BugBear (cryptic)

I've heard of these but never seen one - BB do you have one to show us? (pleeeeease)

Did Stanley offer a version?
 
Has anyone ever measured how much comes off of an iron in a typical sharpening? I never used a two piece cap because I figured if it was a couple of thousandths, it would actually affect the set vs. what you'd have if you redid it by eye.

Nonetheless, the labor for someone using a cap iron a fair amount should be an extra 15 to 30 seconds each time you set the cap, and the ability to plane more before resharpening more than offsets that.
 
@Bugbear

WHAT! :shock: A FRICTIONAL GEAR FOR TRANSMISSION OF POWER! IN A HAND TOOLS THREAD, how dare you sir!
However, know what a fine upstanding gentleman you are, I presume that you are merely in error in your transcription and typography and in fact mean the decidedly amazingly fantastamagorical orgasmatriffic patent D362743

I remain sir, your most fervent admirerer
 
Droogs":3lik423d said:
@Bugbear

WHAT! :shock: A FRICTIONAL GEAR FOR TRANSMISSION OF POWER! IN A HAND TOOLS THREAD, how dare you sir!
However, know what a fine upstanding gentleman you are, I presume that you are merely in error in your transcription and typography and in fact mean the decidedly amazingly fantastamagorical orgasmatriffic patent D362743

I remain sir, your most fervent admirerer

That's the US patent Droogs. Found the same myself and scratched my head but scroll further down the page search to find the Record patent of the same number. Posted a picture further up the page.
 
And another method to experiment with for setting the cap iron 'close'. Attach it to the blade loosely set back 2 or 3 mm from the cutting edge. With a piece of soft wood sat on the bench (poplar [tulipwood], lime, pine, etc), hold the blade, cutting edge down, perpendicular to the wood, parallel with the long grain (usually) and push down. Slide the cap iron down to touch the wood and tighten the screw.

I've never attempted to measure the distance between the cutting edge of the blade and the front edge of the cap iron, but it does generally end up 'close'. There can even be a bit of adjustment through pressing harder or lighter during this procedure. And the method doesn't always work just so - the cap iron can end up a bit squint, or too close, and a bit of fiddling and redoing is needed. I suppose there's also a risk of dulling a freshly honed blade's cutting edge a bit before it's even taken a shaving in anger, but I can't recall this being an issue when I've used the technique, which in reality isn't very often because I don't usually aim to set the cap iron that close. Slainte.
 
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