About thick cap-irons

[Jacob]

....... it stiffens the whole blade assembly but using a thinner blade to allow easy sharpening, and presumably to cut back on materials, thus cost, used.

It doesn't stiffen anything - it nips the blade tight at the edge, whether a thin blade or an old woodie with a thick blade. Material cost difference would be tiny.

And yet most, not all, folk seem to think that a thicker blade is a good thing.

Fashion. Lack of appreciation of the clever engineering of the Bailey design. Think of the safety razor - thin blade tightly held works better than a thick cut throat.

 

[woodbrains]

Hello,

Thin cap irons rely on the flex in the steel to impart a pressure on the leading edge from the tightened cap iron screw. A thick cap iron will not so much, so needs the pressure of the lever cap to apply the pressure at the leading edge of the cap iron. Clifton do this by the hinged arrangement to allow the front piece to 'give' a bit under the lever cap pressure, left one piece, being as thick as they are, it would not happen as effectively. Joining the 2 pieces with epoxy resin will still allow the flexture of the front piece.

Razor blades have nothing to do with planing and cannot be compared as such. In a system that encounters the forces involved in hand planing, the stiffer the blade assy the better (to a point). A 3mm blade is more than twice as stiff as a 2mm one, and when kept flat with a better cap iron, benefits fron a firmer seating on the frog, so adding more stiffness. I don't see the downside of using better performing components to improve the overall performance of the tools.

I have never come across a standard Stanley or Record plane that did not need some attention regarding its cap iron. Some only a little smoothing of the leading edge, but others a complete re shaping, re bending, polishing etc. they are not at all good.

Mike.

 

[Derek Cohen (Perth Oz)]

Good post. Some might remember this thread: 3rd-party-chipbreakers-t76382.html in which it was claimed that the Clifton cap iron design was defective (Cohen, Charlesworth, et al.), when in fact it is not. Far from it, actually. I believe Derek recounted in that thread his efforts to file the slot in the Clifton chipbreaker which most likely ruined an intentional design feature (as another poster in the thread pointed out) and which you have reminded us of in your post above.

Charles, you are making that up. Since you have given the link, go back and read it again.

I stated that there was slop in the Clifton that made it difficult to set close the edge of the blade. After all, that is the point of this thread, and it was there as well. David Charlesworth agreed with me and also fixed his together (with silicon). You suggested something silly to him and he called you bizarre. I think David has excellent insight :lol:

Regards from Perth

Derek

 

[Jacob]

.....Razor blades have nothing to do with planing ...

Really? I'm glad you told me! I've been trying to shave this lump of oak all day. :roll: Now you point it out - I see it doesn't have a beard.

....and cannot be compared as such.

Oh yes they can. The blade assembly is similar, and for a similar reason - to make an easily sharpenable blade in the Bailey, or a throw-away blade in the Gillette, both preferable to the heavy older alternatives.
There were attempts to make a throw-away blade for planes but I guess they weren't viable - they get a lot heavier use than chin shaving, and anyway sharpening isn't difficult (except to our new modern sharpeners of course :lol: ).

 

[Spindle]

anyway sharpening isn't difficult (except to our new modern sharpeners of course ).

All abord who's coming abord :wink:

 

[Peter Sefton]

anyway sharpening isn't difficult (except to our new modern sharpeners of course ).

All abord who's coming abord :wink:

Not playing today just got back from the Daventry show after a long weekend

 

[Trafalgar]

Good post. Some might remember this thread: 3rd-party-chipbreakers-t76382.html in which it was claimed that the Clifton cap iron design was defective (Cohen, Charlesworth, et al.), when in fact it is not. Far from it, actually. I believe Derek recounted in that thread his efforts to file the slot in the Clifton chipbreaker which most likely ruined an intentional design feature (as another poster in the thread pointed out) and which you have reminded us of in your post above.

Charles, you are making that up. Since you have given the link, go back and read it again.

I stated that there was slop in the Clifton that made it difficult to set close the edge of the blade. After all, that is the point of this thread, and it was there as well. David Charlesworth agreed with me and also fixed his together (with silicon). You suggested something silly to him and he called you bizarre. I think David has excellent insight :lol:

Regards from Perth

Derek

Well, regards from Perth indeed. I think it's you who should re-read the thread.

From Gazpal:

"I'm a long term user/devotee of Record Stay-Set cap irons (I assume Clifton's two-piece cap irons are very high quality replica) and have never experienced problems mislaying nosing sections, or with loose fitting parts, or regarding accurate & fine placement for finish shavings. I tend to keep my Stay-Set planes for finer finishing work and my others for hogging off material. You simply position the two-piece cap iron in the same way as a one-piece example, before tightening the screw and setting it in the plane and - with the cap iron set correctly - there's no real need to use thicker irons.

There shouldn't be any need for faffing around with epoxy or silicon sealant when positioning two-piece cap irons, unless you suffer severely from the shakes or have poor hand:eye co-ordination."

... and from Mignal in the same thread:

"Exactly my sentiments. I'm baffled as to why some people seem to have trouble with dropping the nose section or positioning it. I've used a Stayset for 30 years, in an old Record No.6 that I acquired. At the time I'm pretty sure that I didn't even know what a Stayset was. I just used it. I can't ever recall having problems with it, even though the 2 piece cap iron was undoubtedly 'new' to me. I've checked mine yet again. What is remarkable is just how accurately the two pieces fit together. Quite honestly, you would have to call in the boffins from NASA to measure the 'play' in any of mine."

Mignal in response to Charlesworth:

"To obtain that degree of rotational slop in a Clifton chipbreaker would require a very poor fit. That rotaional slop is in respect of the full width of the keyed part.
I cannot detect any slop in that direction, or forward/backward in both of mine. My after market Clifton 2 piece (from Axminster) are around 5/6 years old. I cannot detect that type of slop in my Record StaySet either- obviously much older.
It would be informative if other owners of the more modern Clifton 2 piece would check theirs. I don't doubt what you are saying David but I just wonder if it is 'typical'. After all, I have a LV blade that is (and always was) a poor example. In terms of edge retention it is inferior to my thin Stanley circa 1980's blades. I suspect that what I received was less than a 'typical' example."

... and from Peter Sefton:

"This rotational slip is not present on any of my Clifton's [emphasis added], and I do not suffer with dropping the end section of the chip breaker any more than I drop any of my other tools. The bottom section of the chip breaker often pivots on the centre point connecting it to the main plate, but this is not an issue; it ensures the pressure exerted by the lever cap lays the chip breaker's front edge totally flat on the blade without creating any other stress or bend within the cutting iron that may lead to flutter."

... and Mignal again:

"Derek. What part of the Clifton chipbreaker prevents it from being set within 0.3 mm (or closer) to the edge?
I can do it with simple ease but then again I don't drop the nose section either."

... Mignal yet again:

"Derek. I have numerous chipbreakers. I've long lost count the actual numbers that I own and have used over the years.
The Clifton chipbreakers (and the staySet) that I have show NO play, either rotational or forward/backward. That appears to be the same experience of the vast majority of people who have replied to this thread. I simply do not recognise the problems that you refer to. None of them. The method of placing blade and chipbreaker into the plane requires a slightly different technique but that technique can be acquired in seconds. It is so simple that I'm genuinely shocked that you didn't find the solution of using the index finger on the nose piece.As such the Clifton chipbreaker is capable of setting with ease and your assertion that it is only suitable for rough work is clearly wrong. Perhaps your particular chipbreaker is a poor example but I guess we all experience poor samples of manufacturers products. If I did a review of my LV Plane blade it would rate lower than the 1980's Stanley blades that I own. It's obviously one that should not have got through, but it did."

END QUOTE(S).

As I said (and obviously several others as well) in this thread and in the other -- there is nothing wrong with the Clifton chipbreaker design. You were tinkering with something that simply did not need to be tinkered with. Cliffy chipbreakers work fine. They take a close setting and will hold it. Any assertion that they don't or can't perform all of the functions any chipbreaker is supposed to perform (pre or post "Kato & Kawai") is pure codswallop. If you don't understand the subtle design features or how to set one up properly, then humbly ask for assistance rather than ruining one with what you assumed to be fine fettling and improvement and then denigrating it on these woodworking forums. You don't know as much as you think you do, a fact clear to a lot more people than you would imagine.

If you feel that you received something with a manufacturing defect (of an otherwise competent design) then send it back and/or ask the manufacturer for help. This is precisely what you encourage Lee Valley customers to do rather than complaining on the internet. Follow your own advice.

 

[Vann]

OK - now that someone else (of superior standing) to me has raised this I am going to jump on board and profess a total lack of understanding how the Clifton and StaySet cap-irons can possibly work as well as a one piece. Unless I am missing a fundamental aspect of the purpose of the cap-iron it surely doesn't support as well as a standard version.

The 2-piece provides better support.

The patent drawing of Mr Bailey's double iron shows the cap-iron laying parallel (flat) on the iron right down to the point where it begins the distinctive hump. So, with the lever-cap down tight, the original Bailey design offered a three ares of pressure between the two irons.
- at the top where the cam applies pressure;
- at the bottom (leading edge);
- and immediately above the hump in the cap-iron.

The latter two pressure zones would be about equal, as the bottom edge of the lever-cap rests on the highest point of the hump, therefore the forces would be transmitted roughly equally to both top and bottom of the hump.

While the design is great, in practice I've seen very few cap-irons of this design that are actually the correct shape. If the bottom edge is not bent down enough the cap-iron will not touch the cutting iron, making the whole thing useless. So manufactures (including Stanley) ensured that the bottom edge is bent down more than enough. This causes the top end of the hump to not be in contact with the cutting iron - and the result is the bending of the cutting iron we're all familiar with.

An iron with a slight bend will not sit flat on the frog, unless maybe the lever-cap is clamped up excessively tight. So it has just two areas of contact with the frog-
- at the top where the cam applies pressure;
- at the bottom (leading edge).
The area above the hump in the cap-iron is suspended above the frog.

When the tip of the cutting iron hits a hard bit of grain the edge attempts to dig in. The end of the iron tries to pivot about the lower pressure point, and as there is no restraint above that point until near the cam the top, the iron flexes slightly and - hey presto - CHATTER.

What the two-piece cap-iron does, is it takes away any resistance to holding down the cap-iron flat on the cutting iron, and in turn onto the frog, at that important point about 20mm above the cutting edge. It returns the cutting iron to Bailey's original concept. That the Record & Clifton cap-irons are thicker is just a bonus. It probably would have been difficult the manufacture them in thinner material (the Record patent shows a hinged design).

Even the thicker Lie-Nielsen, Hock, etc. 1-piece cap irons look like they would exert a slight bending force on a cutting iron - which is probably not enough to bend a thick iron, but would probably bend a thin Stanley type iron.

HTH (and you haven't got bored and fallen asleep (hammer) )

Cheers, Vann.

 

[Vann]

Be it known that I, LEONARD BAILEY, of Boston, in the county of Suffolk, and State of Massachusetts, have invented a new and useful Improvement in Bench-Planes...

My object is to use Very thin steel plane-irons, and in so doing I nd that they are liable to buckle under the pressure of the cap, which causes them to chatter, and makes them otherwise imperfect; and my invention consists in the providing of an auxiliary point of contact between the cap and plane-iron, and at the point where the plane-iron tends to buckle or rise from its bed or base, and thus have a pressure at that point in addition to that at the cutting-edge, which iirmly holds this thin plane-iron to its bed.

The cap-iron, as commonly constructed, that is, as shown at D, in tig. 3, when applied to the plane-iron E, will rest thereon only at the extreme lower end of the cap-iron, and also at or very nearits upper end. There will be along angular space, between the two irons, when they are clamped together by the holding-devices which are represented in figs. 2 and 3, at A, B, and C, and consist of a screw, A, a bearing, B, and ay cam-lever, C, arranged in a manner well'known.

The diiiiculty experienced from the construction of the capiron with the single bend a, is, that it allows of vibration of the cap-iron and the plane-iron while in use, such vibration being productive of what joincrs term chattering, and consequent defective operation of the plane.

In carrying out my improvement, I make the cap-iron with an additional bend, b, (see figs. 2 and 3,) at a short distance back of its lower end or toe, or at a distance therefrom equal to about double the distance at which such lower edge or toe is to be from the main benda, or the toe of the bearer B, the same being as shown in figs. 2 and l, so as to cause the cap-iron D to bear on the plane-iron E in three places, or at the toe and auxil-V iary bend of the cap-iron, and along from such bend to the heel 'or upper end of the cap-iron. This construction or formation of the cap-iron D completely obviates the diiculty above mentioned, and is a very valuable and useful improvement.

Cheers, Vann.

 

[MMUK]

MM - That logic must surely dictate that you would be heavier standing on one foot?

Not heavier, just that your weight would be concentrated in a smaller area, thus greater downward pressure.

 

[Phil Pascoe]

If you weighed 15st and you stood on both feet on a scales the scales would read 15st. If you then stood on one leg on the same scales, the scales would still read 15st. If you are saying that the pressure is exerted further away from the pivot point, then yes, you are correct although over a few mil the difference would probably be academic.

 

[GLFaria]

Thanks, Vann.

But, if the idea is for the cap-iron to rest on the iron at three places, why is it that every cap-iron I have seen (not that many, but several), when not subject to the pressure of the tightened cap-iron screw, only touched the iron at two places - at the back and at the front? An then, when the screw is tightened, the cap-iron flexes until it rests fully against the iron (with the exception of the arched area), which becomes hopelessly flexed too. However, if one does not fully tighten the cap-iron screw, it will not stay securely in place.

What should one do to such a cap-iron? Bend the arched part back so it doesn't exert so much pressure on the iron, but just barely touches it?

 

[MMUK]

If you weighed 15st and you stood on both feet on a scales the scales would read 15st. If you then stood on one leg on the same scales, the scales would still read 15st. If you are saying that the pressure is exerted further away from the pivot point, then yes, you are correct although over a few mil the difference would probably be academic.

I'm not talking about weight, I'm talking about pressure :roll:

Increase the footprint, reduce the pressure. Decrease the footprint for the same load, the pressure increases.

 

[Vann]

I have this old dog of a plane (spare parts) with one wing broken off... :shock:

...which allows a view of the cap-iron, cutting iron and frog seating. This shows no contact from the lever-cap pivot screw, down.

I thought I'd try a few double irons, to see if any seat the way Leonard Bailey intended.

1950s Stanley irons - Fail

1960s Stanley irons - Fail

1940s Stanley irons - close, but not quite.

Marples irons - Fail

1950s Record irons - Fail

1950s Record irons - Fail

1950s Record irons - Fail

Wartime Record 2-piece - look at that !! 8) Nice and tight all the way down to the top of the deflector. This is why I believe the Record/Clifton 2-piece is a good design of Cap-iron - it achieves what Leonard Bailey set out to do in 1867.

Cheers, Vann.

 

[Corneel]

While you are absolutely correct Vann, in practice you almost never get chatter when you pull the frog back so the iron rests solidly on the sole. This lowers the pivot point seemingly enough to make the matter mood. When you push the frog forward to close the mouth, the pivot point raises up, increases the lever two times or so and chatter is possible.

The two piece capiron is a nice design, but in reality the Bailey design works very well in most circumstances, even with the less perfect examples. The Bailey design has been a tremendous succes, much more were sold then the Record ones.

I think that I prefer the two point contact of the Baily capiron instead of the correct three point contact, when setting the capiron very close to the cutting edge. You want good solid contact down there, otherwise shavings might force themselfs a way under the capiron.

 

[Phil Pascoe]

If you weighed 15st and you stood on both feet on a scales the scales would read 15st. If you then stood on one leg on the same scales, the scales would still read 15st. If you are saying that the pressure is exerted further away from the pivot point, then yes, you are correct although over a few mil the difference would probably be academic.

I'm not talking about weight, I'm talking about pressure :roll:

Increase the footprint, reduce the pressure. Decrease the footprint for the same load, the pressure increases.

:roll: And I'm talking about pressure, too. The overall pressure exerted on the blade is going to be the same no matter what proportion of the cap iron touches it.

 

[Paul Chapman]

Excellent set of photographs, Vann, which clearly show why the Record Stay Set/Clifton two piece cap irons are so good. Thanks for posting.

Cheers :wink:

Paul

 

[Jacob]

He's got a point of course but I wouldn't say fail to all the others. If the blade is flat against the frog and tightly nipped at the pointy end the cap iron is doing its job.

 

[Paul Chapman]

If the blade is flat against the frog

But it probably won't be when using the bent metal-type cap iron and a thin blade because the cap iron tends to bend the blade.

Cheers :wink:

Paul

 

[Jacob]

If the blade is flat against the frog

But it probably won't be when using the bent metal-type cap iron and a thin blade because the cap iron tends to bend the blade.

Cheers :wink:

Paul

Then the cap iron just needs bending a bit to make it all a good fit. The blade unit is pinned tight at both ends but needs adjusting to lie flat in the middle.