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Paul Sellers says cap iron position doesn’t matter

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JohnPW

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It only matters if planing "difficult" grain. I doubt he was planing against the grain in that video.
 
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scooby

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Oh popcorn time..or is that only reserved for sharpening threads?

Not that it matters, but I've always set mine about the same distance as he said (just over a mm). The cap irons on my planes aren't the tightest so setting super close just causes problems.
 

Ttrees

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That was more than a 1/32", and no mention that the leading edge needs to be honed at around 50 degrees if it is to work at that distance.

A lower profile edge of the cap iron is what most folks likely have, so it would need to be set closer to work.
That becomes a problem if one want's the tiniest of cambers on the other smoother plane that they should have...(which is set at half that distance)

The camber of the cutting iron must be so fine that it is difficult to see, until paired with the cap iron,
but evidently effective from the narrower shaving of a plane when the cutter is not advanced to correct depth, and when adjusted properly will achieve pretty much full with shavings, and give unbeatable results.

i.e ... on difficult timbers, the cutting iron will likely need to be honed straight across if the leading edge of the cap iron is not steep enough.
Camber is nice to have, so the cap iron will need to be further away from the edge, and I can't do that on the smoother without it being around 50 degrees.

Edit, the camber on the smoothing plane will be so fine, that the cap iron can be set closer if need be.
And for those living under a bridge for near the last decade...
The mouth must NOT be set closely, or it chatter about and refuse to work.
Get a candle because the plane will have more down force compared to the lateral force experienced when planing before, without the influence of the cap iron.
Notice this when planing a straight edge that the plane will have less tendency to dive off the ends and create a bow.

And obviously the most important part about being able to plane any species of timber against the grain with flawless results, no scraper needed for planing flat work ever again, just plane as it were flawless uniform material without ever needing to reverse direction around a knot or reversing grain.
 
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ivan

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If you bother to search for it, there's an interesting macro video of an edge cutting timber, on line, made in a Japanese University, as teaching material for school students.This shows with-grain and against-grain cutting. There's a translated version, although only sub titles. There's also a paper by a Dutch? chap which looks at quality and cutter wear at various pitches and cap iron angles. To work, the cap iron must be set by "thou" not inches!
There's also info on downward and forward pressures needed to get a cut, which interstingly concludes that a steep pitch and close cap iron is an easier push than the equivalent bevel up, when measured by the quality of the resulting cut (bevel up requires steeper angle to match the bevel down+close cap iron). Bear in mind, ultimate finish quality is not required from all planes in the kit.

Wooden planes (nor infill wood) do not "damp vibration". Vibration in planes is caused by thin irons. The pressure on the cutting tip tends to raise the body of the cutter from the frog, about 2 to 3 cm up the blade, by pivoting on ther heel of the bevel. The slight bend causes the cutter tip to dig in a fraction and then spring out. As posted here before I have measured this on a bog standard plane with a clock gauge. This plane has always cut with a brrzip sound. The stayset 2 piece cap iron prevents this, as will the 2 part Millers Falls lever cap. The original Baily patent is worth looking up, when you'll see that the the chipbreaker is formed so as to lie fully flat on the blade, with both sides of the curved part touching on the blade. Thus the thin blade is designed to be held down by the lever cap at 3 points, not 2. Pity the manufacturers have forgotten this! Over bending the chip breaker so the blade is held off the face of the frog is a definite recipe for vibration.

Thicker blades are more rigid. Double the thickness is 8 times more resistant to bending. The bevel will be twice as long, so the overall effect is reduced to 4 times. Wooden planes and infills do not use thin blades - possibly even 3 x thicker (9 times stiffer overall) so not likely to chatter. Nothing to do with the wood!

Thick blades take no longer to sharpen than thin, if you use the 2 bevel "grinding angle + sharpening angle" approach, especially if you are hollow grinding on a wheel, like a Tormek. DC's Ruler Trick will also concentrate the flat side sharpeing directly in the area of wear (see paper below)

So there you have it - bevel up planes are harder to push and need more downward pressure than bevel up, for the same planing quality.
The chipbreaker (or whatever you call the blade's intimate companion) will not break chips unless properly set, which means no more than 12 thou (0.3mm) and more like 4 thou (0.1mm) from the edge, for tricky timber. Just like grandad showed me around 1950!

Bear in mind, finesse is not needed on every plane. Where it is, use a flat, not bent cap iron, sharpened to the appropriate angle, and curved to match the blade of your smoother. If the cap iron is completely flat, you can gently roll a tiny hook (scraper style) at the correct angle to ensure no shavinges get trapped-thanks again grandad!

Video:
Paper: Mechanics of Chipbreakers
 

Ttrees

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. To work, the cap iron must be set by "thou" not inches!

The chipbreaker (or whatever you call the blade's intimate companion) will not break chips unless properly set, which means no more than 12 thou (0.3mm) and more like 4 thou (0.1mm) from the edge, for tricky timber. Just like grandad showed me around 1950!

Bear in mind, finesse is not needed on every plane. Where it is, use a flat, not bent cap iron, sharpened to the appropriate angle, and curved to match the blade of your smoother. If the cap iron is completely flat, you can gently roll a tiny hook (scraper style) at the correct angle to ensure no shavinges get trapped-thanks again grandad!
That's a bizarre statement to read, that you can't use the imperial
measurement to set the cap iron.
You must try honing the cap edge, around 50 degrees instead of rolling the edge,
and see those shavings coming straight out of the plane, all nice and burnished and the plane leaving a lovely glossy finish as you've noticed already.
The only difference being the cap can be set further away.
Some like Warren Mickley suggest honing it much steeper than 50, I think I recall him suggesting around 80 degrees, presumably for more camber.
The influence of the cap iron isn't just for smoothers.
My no.5 1/2 will hog off material when set at 1/32", or maybe when set just under/ and iron honed to match it, for a denser batch.
Rarely do I need to reach for the smoother, which is normally about half that distance away from the edge, but can be adjusted closer without re-profiling the cutting iron, as the camber is so fine.

I've got away without damaging the cap iron at times, where the iron got damaged before.
Makes sense to me to hone at 50 degrees, even if one didn't want camber.

Tom
 

Jacob

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.... a Dutch? chap which looks at quality and cutter wear at various pitches and cap iron angles. To work, the cap iron must be set by "thou" not inches!
He's wrong though isn't he :ROFLMAO:
There's also info on downward and forward pressures needed to get a cut, which interstingly concludes that a steep pitch and close cap iron is an easier push than the equivalent bevel up, when measured by the quality of the resulting cut
Yes and no. If the cap iron is too close it may be really difficult to get a cut on easy wood though it may scrape well on something difficult. But yes a cap iron will tend to help in many circumstances as it works as a chip breaker and helps roll the shavings
Vibration in planes is caused by thin irons.
No it isn't. It's caused by loose blades badly fitted, amongst other things. A thin blade firmly clamped down by a good fitting cap iron and lever cap will tend not to vibrate. Another detail is to set the frog dead in line with the mouth so that the back of the blade is being supported as much possible where it's most important - just behind the cutting edge.
T........The original Baily patent is worth looking up, when you'll see that the the chipbreaker is formed so as to lie fully flat on the blade, with both sides of the curved part touching on the blade. Thus the thin blade is designed to be held down by the lever cap at 3 points, not 2. Pity the manufacturers have forgotten this!
It would need another lever on the cap to do this which is why the idea was dropped
Over bending the chip breaker so the blade is held off the face of the frog is a definite recipe for vibration.
I agree - and nobody does that
Thicker blades are more rigid. Double the thickness is 8 times more resistant to bending. The bevel will be twice as long, so the overall effect is reduced to 4 times. Wooden planes and infills do not use thin blades - possibly even 3 x thicker (9 times stiffer overall) so not likely to chatter. Nothing to do with the wood!
No it's to do with sharpening and ease of set. The Bailey design saved millions of hours of fiddling about. It made a thin blade + cap iron + lever cap perform as well as a fat one but much easier to use
Thick blades take no longer to sharpen than thin,
Not true at all, how could this possibly be? 3 times as much metal takes 3 times longer to remove..
Do you really think that the abandonment of old woodies and thick blades was just a mistake which nobody noticed? Seems unlikely to me!
 
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Phil Pascoe

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Not true at all, how could this possibly be. 3 times as much metal takes 3 times longer to remove...

That's why most sensible people grind their irons and don't hone the whole of it.
 

Jacob

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Not true at all, how could this possibly be. 3 times as much metal takes 3 times longer to remove...

That's why most sensible people grind their irons and don't hone the whole of it.
You have to grind with a thick old iron.
But you can get away with a light touch on thin blades, that's the whole idea. e.g. Paul Sellers style with three stones one after the other. If you are on site with just one stone that's no prob with a thin blade.
Actually you can freehand grind an old woody blade if you have to - it helps to bolt it to a lath so you have a handle and can put max effort and speed into it. With the right coarse stone 10 to 20 minutes perhaps.
 

Ttrees

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That's often the fast part for me!
I find honing the iron to get that perfect camber is much more
of an issue.
What I thought was acceptable before would not be even enough nowadays.
I have tried numerous bloomin techniques and am always learning and changing.
I just couldn't replicate David's method's of getting the camber even.

I've since went on to using the cheap diamond hones and water
as my skin is porous, (couldn't get oil off my hands)
and find that not just leaning or tilting but locating your fingers where you want to remove material works a lot better than leaning.

David reckons directed pressure is a good term for it, but to me sounds like leaning using a honing guide,
That's a little bad habit one can pick up from one of those yolks,

I haven't found a more reliable way freehand of getting the camber even than this, so thumbs up to David Weaver again.
God knows how long that would have taken me to figure out, if it were to happen at all.

Tom
.
 

Adam W.

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Not true at all, how could this possibly be. 3 times as much metal takes 3 times longer to remove...

That's why most sensible people grind their irons and don't hone the whole of it.
But you have 3 times the surface area contact with the stone, so one push will remove the same amount of material, surely.
 

ivan

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3x the work? *not if you grind on a wheel at 25 deg and sharpen at 30 (or more)
*thou, and inches are both imperial measure-or they were in my schooldays.
*a close set cap iron is not needed for most planing, only difficult stuff.
*most standard blades with chipbreaker / cap iron attached become bent as the screw joining them is tightened. The chipbreaker is over bent by the maker to ensure no shavings get caught under it. Writers often advise this should be done!
*the original bailey patent design mentioned above holds the iron down to the frog at 3 points under a perfectly common lever cap. Google it and see for yourself.
*David Charlesworth sugests imagining the edge of the blade is numbered 1,2,3,4,5 across the width. 3 is the middle. You give the same number of strokes with pressure at each of 2, and 4, and then perhaps double that number at each of 1, and 5. Adjust by trial and error for more curvature if needed. For a smoother, a fine thin shaving should taper away to nothing at each side. If you use a honing guide, it must have either a narrow, or a barrel roller, to allow easy tilting. If you grind the edge straight, and camber only when sharpening on the finishing stone, you can just about see curvature in the shape of the highly polished strip at the edge of the bevel.
*you could probably knock up a deliberately hollowed diamond sharpener from one of those cheap ebay chinese diamond plates. At 1mm thick, I suspect you could glue a 3000 grit one to an old tile, with the edges raised up by a single sheet of thin paper. The bend in the plate would be very small, and with luck araldite or pu would hold. I believe a hollow diamond sharpening plate was actually available in the USA, but probably cost more than 3 quid...
 

ivan

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Re sharpening the flat cap iron / chipbreaker mentioned above: For the smoother I usually sharpen the cap iron at about 50 deg and then gently roll on the hook at about 10-15 deg more. The shaving is thus turned by some 60 odd degrees. The paper mentioned in the earlier post shows how the cap iron also wears at close settings, so a well designed one for a smoother shouldn't be made of soft mild steel...
 

Jacob

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3x the work? *not if you grind on a wheel at 25 deg and sharpen at 30 (or more)
3 times the work using the same methods, obviously. Though in fact you don't need to with thin blades - you can skip the grinder altogether if you do it a little and often - which also means sharper more often
...
*a close set cap iron is not needed for most planing, only difficult stuff.
Agree. For most purposes it doesn't matter much as Sellers points out. 1/32" is a bit tight for soft stuff.
*most standard blades with chipbreaker / cap iron attached become bent as the screw joining them is tightened. The chipbreaker is over bent by the maker to ensure no shavings get caught under it. Writers often advise this should be done!
The blade back needs to sit flat on the frog, yes it can be badly adjusted - you just need to bend the cap iron and/or the blade a touch
*the original bailey patent design mentioned above holds the iron down to the frog at 3 points under a perfectly common lever cap. Google it and see for yourself.
I think you'll find that that was one of many designs - found to be not worth the bother. In fact the common set up approaches having 3 contact points, the two sides of the "bump" and the point under the lever cam. The stayset design does it more explicitly
......For a smoother, a fine thin shaving should taper away to nothing at each side.
For most planes in fact. Couldn't quite follow all that other stuff - a camber is something which occurs more or less unaided with freehand sharpening whether you want one or not. But you do usually and it's very easy to increase it if you wanted to.
Modern sharpening looks more and more like alchemy with magic numbers and formulas all over the place! Big problem is the honing jig itself which creates more probs than it solves.
 
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Jameshow

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Do you think the heyday of handmade furniture and architectural woodworking was in the period of the wooden plane rather than the bailey pattern by which time efficiency and the finer details didn't matter so much with the advent of powered woodworking machinery.

Just a thought

Cheers James
 

Jacob

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Do you think the heyday of handmade furniture and architectural woodworking was in the period of the wooden plane rather than the bailey pattern by which time efficiency and the finer details didn't matter so much with the advent of powered woodworking machinery.

Just a thought

Cheers James
Bailey plane came in with industrialisation and a parallel huge increase in design complexity made possible by machines. Design got more fussy, not less. 1851 Great Exhibition provoked the arts n crafts reaction. Maybe plain and elegant Georgian reflected the sheer difficulty of doing stuff with these great clunky tools, all by hand?
 

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For London, I think the period after The Great Fire was a very spectacular time for architectural woodwork. They produced very elegant interiors.

But some regional architecture in 1500 was truly awe inspiring......Clunky wooden planes and all.

Roodscreen-15th-Century-Carving-Wood-Coloured-Vaulting-Medieval-Uffculme.jpeg



Uffculme rood screen.
 
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