bendy cap irons

[nabs]

with apologies to all those people who find the topic of plane cap irons mind numbingly boring and annoying...

I have been doing some research into the thrilling topic and was very interested in Vann's observations about the difference between Leonard Bailey's original patent and the typical implementation on the planes he owns:

https://www.ukworkshop.co.uk/forums/ross-no-4-plane-t89988-30.html
I thought I would start a new thread rather than reply to the old one, which the OP started on an unrelated topic

just to lay my cards on the table: I am a woodworking dunderhead (honestly, I am completely clueless) who is just starting out learning about the tools of the trade and in the process has become slightly obsessed with all the controversy around cap irons. I can't really explain why this was so, but I did a lot of research as a result and thought I had it all clear in my mind until I read Vann's post.

If you read the patent:
http://www.google.com/patents/US72443
it is clear that the intention was to make the cap iron apply pressure to the blade not just near the heel and toe of the cap iron (as with the previous design that had only a single bend towards the toe) but at three places: "at the toe and auxiliary bend of the cap-iron, and along from such bend to the heel 'or upper end of the cap-iron". And as Vann says, this is clear in the image also (c.f fig 2):

however, in practice - at least in Vann's examples (and mine too) the auxiliary bend does not contact the blade at all.

Rather than get into another discussion on what cap iron design is best, perhaps we could assume for the sake of argument that these examples are representative of 20th century bailey planes and - on the basis that Record, Stanley etc sold rather a lot of them - that the design works adequately in practice to solve the problem Bailey was trying to eliminate:
"The difficulty experienced from the construction of the cap iron with the single bend ..., is, that it allows of vibration of the cap-iron and the plane-iron while in use, such vibration being productive of what joiners term chattering, and consequent defective operation of the plane."

So to the point, does anyone have an example of the "Bailey" cap iron that does make contact with the blade all the way between the auxiliary bend and the heel? Are the end of the 19th century ones different?

I am curious to know whether the patented design actually had some other disadvantage that caused it not to be widely adopted.

cheers and sorry again for those who are not looking forward to yet another cap-iron discussion.

 

[Paul Chapman]

I've never seen a Bailey-style plane where the cap iron functions as described in the patent you referred to. All of the Bailey-style cap irons I have and have seen make contact with the blade at only two points.

The problems with the Bailey design in my experience are as follows.

1. It uses thin blades.
2. The design of the Bailey-style, bent metal cap iron causes the thin blades to bend.
3. Frogs on most Bailey-style planes are very badly machined and the surfaces are not flat.
4. The alignment of the frogs on many Bailey-style planes is not accurate.

Some of these problems can be corrected by doing a lot of work on the planes and changing the blades and cap irons. However, a better option in my view is to buy a Bedrock-style plane in which the frog assembly tends to be accurately machined and to use thick blades and the Stay-set style cap iron, which was designed specifically to overcome the design faults in the Bailey-style cap iron.

Cheers :wink:

Paul

 

[Corneel]

I would have to go out to the shed and diassemble some planes, but I go to friends in a few minutes, and I think my wife wouldn't agree.

In the mean time I must say that I am a huge fan of the original Baileys with the thin blades. They are superb. No need to exchange with ugly, thick, expensive, aftermarked stuff. The originals often do need quite a bit of work, but you only need to do that once. After that they shine in easy of sharpening and great planing performance.

 

[Cheshirechappie]

Hello nabs, and welcome to the forum!

There was a (rather rambling) discussion about this some months ago - bailey-style-planes-thin-irons-and-cap-irons-t92531.html

 

[worn thumbs]

I own seven or eight Bailey style planes and don't recognise the theoretical deficiency at all.Each and every one works well.It may help that they are actually sharp and set to remove sensible shavings.

 

[David C]

UK 1970's Stanley blades were rather like cheese, and not up to hardwoods.

Replacement blades were like manna from heaven!!

If I remember correctly Hock first and Japanese laminated second.

Thin C/Bs were OK once fettled but several experiments showed that a heavy c/b produced improved performance.

David Charlesworth

 

[nabs]

thanks all for the comments, and I did see the "thin irons" thread the other month - my conclusion is that Mr Bailey knew both the benefits of a thin iron (cheaper to make, easier to sharpen) and the downsides (increased chance of flex/vibration) and therefore invented a modified cap iron to reduce the downsides.

I defer to the more experienced amongst us regarding the relatively poor finish on many "bailey" cap irons, although I have to say on my x5 ebay planes (all pre 1960s Records) it only took a couple of minutes rubbing the toe on sandpaper to get it to mate cleanly with the blade, and only in one case did it make a noticeable difference - this was an example where the cap iron had a couple of nicks in it which (before flattening) were causing shavings to get caught clogging the plane.

It took another few minutes to polish and shape the "hump", although to my untrained eye I could not tell any difference in performance. The trouble is, I think, that all these little modifications collectively may improve performance, but when you are starting out they pale into insignificance compared to the impact of having a very sharp blade (as I realized once I finally cracked how to do that part!).

so, back to the patent - if the disadvantage of the thin cutting iron is it can flex and the auxiliary bend is supposed to reduce the chance of this happening then how is it so?

my reading of the Bailey patent is that it says the part of the plane the blade rests on that is immediately before the cutting edge acts like a fulcrum, causing the section of the blade further back to rise from the bed of the frog when the blade is pushed into the wood. It seems intuitive that the blade would tend to flex up and down over the fulcrum as the pressure on the blade varied during the stroke (chatter?)

Bailey's fix is to include a second auxiliary bend in the cap iron such that some of the pressure from the capiron screw and the lever cap is pushed immediately behind the fulcrum.

Now bear with me here, because my engineering knowledge is as limited as my woodworking skill, but it seems to me that although some degree of extra tension is applied immediately in front of and behind the fulcrum , the fact that the rest of the cap iron lies flat on the blade means the pressure is distributed over a larger area and therefore lessoned. In other words, although the newly created arch means that some of the pressure is directed to the area where it is needed most, the fact that it was reduced overall counteracts the benefit.

My related theory is that the design that was actually implemented and that we see in our planes from the 1st half of the 20th century is a compromise, attempting to get the best of both worlds: leaving a pronounced bend in the length of the cap iron means it will place the cutting iron under more tension than were it simply laid flat on top, and adding an auxiliary bend helps to direct some of the pressure nearer the fulcrum (albeit not actually right behind it) and this reduces the chance of vibration.

I have done a hyper-realistic artists impression below.

QED!

One last point, for which some evidence was provided in the aforementioned "thin iron" discussion, a side effect of the design is that there is more pressure at the heel and the toe of the blade than elsewhere, creating a tendency for the part of the blade in between to flex away from the frog - thus giving cause for those of us, me included, to wonder why we bothered flatting the face of our frogs since it is likely for the most part it does not make contact the blade in any case, apart from at the top and the bottom.

Is any of this important in the real world? Apparently not since 100 of thousands of bailey plane users seem to have been able to make effective use of them without giving it a moments thought, but I still like to know

 

[Vann]

...So to the point, does anyone have an example of the "Bailey" cap iron that does make contact with the blade all the way between the auxiliary bend and the heel? Are the end of the 19th century ones different?

Some early USA Stanleys (end of the 19th century/beginning of the 20th) have cap irons much closer to the patent shape. Without going out to my "shed", I can't recall if I have any that fully comply.

Certainly, by the time Stanley began manufacturing in UK, their cap-irons no longer followed the patent. Nor did Record cap-irons (of the Bailey type).

Is any of this important in the real world? Apparently not since 100 of thousands of bailey plane users seem to have been able to make effective use of them without giving it a moments thought, but I still like to know

Yebbit, there must be a similar number that have been bought and not been able to be used - witness the number of almost unused examples available through internet auction sites. Though I admit that the faulty cap-iron shape is but one of many issues with a modern Stanley/Record, that combine to stump the newbie.

Yes, planes with this shape of cap-iron can be made to work. Similarly I'm sure a plane with a mis-shaped frog can be made to work with the addition of a thicker cutting-iron. But I think that a plane with a minimum of faults will be likely to perform better when the going gets really tough.

Cheers, Vann.

 

[nabs]

yes that is a good point Vann - in fact all but one of my Record planes arrived from ebay in a basically unusable state. I wish now I had been a bit more scientific and tried to gauge the impact of simply sharpening the blade vs sharpening the blade and doing all the other flattening and fiddling I did, that way I would be better placed to comment on the relative benefit of each step.

Also, since the main impetus behind the bailey design seems to be to create something that is straightforward to engineer and therefore relatively low cost, I agree that the main trade-off of the design - namely passing some of the final setting up steps to the end-users - will deter some people who do not have access to teachers to tell them how, or who lack the patience to wade through all the confusing advice on t'internet in order to discover it themselves.

Having been down the later route myself I think my advice to others in the same situation would be - if you have the cash - to pay for a modern high-end plane where some of the compromises of the bailey design are mitigated (better engineering tolerances, thicker blades etc) just to avoid them being deterred by the frustrations of getting a cheaper and older one to work.

Having said that, I have to say that my experiences getting old planes to work has been positive and very satisfying , so if a new woodworker was prepared to try it I would certainly encourage them to have a go - you really don't have much too lose with a 20 quid ebay plane and actually it is not that difficult.

 

[Tony Zaffuto]

Can't remember which book it was, maybe The one by Garret Hack, or possibly by our own David Charlesworth, but I remember discussuin on the "hump" and some slight bending of the chipbreaker to make sure it "mates" with the blade correctly. I do recall David's instructions on working the "toe" to mate correctly.

 

[Cheshirechappie]

It's quite true that a sharp cutting iron cures quite a lot of planning problems!

There's no such thing as a plane design that is perfect in all circumstances. All of them are compromises to some extent. Some people feel that the Bailey type perhaps compromise a bit too much, and whilst they cope well enough most of the time, they struggle when the going gets really tough. That's probably why the modern premium planes tend more to the bedrock, thick casting, thick iron designs.

The best bet with planning practice is not to over-think it. Just keep a sharp iron, and get to know your planes and what they'll do. The only way to find out if they are in any way deficient for the kind of work you want to do on the types of timber you want to use, is to use them. Then decide if there's any milage in trying other types. Unless, of course, you just feel like trying a few different planes out of curiosity or in the spirit of scientific investigation......which is, of course, entirely different from plane collecting!

 

[Corneel]

I finally got around to have a look at my pre-1914 Stanleys. None of them have the patented three point capiron contact. And on all of them the blade is bend upwards when fastened to the capiron and touches the frog only at the top and bottom.

They all work perfectly allright. I think the Bailey design is very fault tolerant. And the old ones were made to a rather high standard. My long planes (6 and 7) came to me very flat in the sole. I had to do some work to the #3 and #4 to remove a hump behind the mouth. On all of them the fit of frog to bottom was very good. Only my #5 is a little wobbly, but that doesn't seem to hurt performance. It also has a fault in the lateral adjuster (someone replaced the pin with a screw) and now the blade rests on the adjuster instead of the frog. Doesn't harm either.

The Bedrock doesn't really add a whole lot to these older Bailey designs. Chatter isn't really much of a problem in planes anyway, as long as the blade is sharp. There is a typical problem, skipping, when the edge enters the wood, but that is mostly user error, when you don't put pressure on the plane in the right spot. A thicker blade doesn't cure that.

 

[nabs]

thanks for checking Corneel. I think you make a very good point about the way the design allows for a degree of error in the manufacturing process, and I see that as part of the genius of Bailey's design.

For my part I did do a little work to improve the fit between the frog and the soles/blades in my planes - they certainly weren't perfect - but since each of them had clearly been well used in the past, despite these minor defects, I now wonder if it this work made any practical difference.

 

[Vann]

There's no such thing as a plane design that is perfect in all circumstances.

I think you make a very good point about the way the design allows for a degree of error in the manufacturing process, and I see that as part of the genius of Bailey's design.

Ahh, but that's my point - this isn't Bailey's design. His design has three specific areas of contact between cap & cutting irons.

Cheers, Vann.

 

[Corneel]

The whole plane is Bailey's design. It is much more then this patent of the capiron that doesn't quite work out in real life (like many patents).

I can't stand up for the original condition of my planes. They are over 100 years old. Hard to say what all happened in the mean time. They might even not have the original capirons. The surface has detoriated enough not to be able to see any lettering.

 

[Cheshirechappie]

There have been so many minor incremental changes to the 'Bailey' design of plane over the years, it's rather hard to say whether most are actually Bailey, or Bailey-with-Stanley-modifications. Or even 'based on Bailey but not quite the same' - Record Stay-Set, perhaps?

Vann - I agree completely that most thin bent cap-irons do not conform to Bailey's specific design set out in his patent, and that his specific design is the better arrangement.

 

[ED65]

In the mean time I must say that I am a huge fan of the original Baileys with the thin blades. They are superb. No need to exchange with ugly, thick, expensive, aftermarked stuff.

+1! There is a growing mountain of anecdotal evidence that there's little real improvement in performance. The main difference can be in sharpening frequency, which isn't an issue for many users.

 

[ED65]

Just a quick observation WRT what Bailey himself thought important, from what little photographic evidence I can find his Victor and Defiance planes both do seem to have cap irons that made, if not complete at least much better, contact with the cutting iron than typically seen on Stanleys.

 

[lurker]

CC

You missed:
or Bailey-with-Stanley-modifications with accountants overruling designers versions (ie post 60s)

And this is where the water gets muddy as there are now so many mongrels out there.
I'm sure others are like me: I have planes that I have built from maybe 3 donors or modified with 2 piece cap irons or even with home made blades in them.

We have posts here saying "this is my pre war (or whatever) stanley" when clearly its a lot newer than that. I say nothing because I dont want to hurt peoples feelings.

As for e-bay: I have spotted a silverline described as a vintage plane :lol:

 

[D_W]

There's no such thing as a plane design that is perfect in all circumstances. All of them are compromises to some extent. Some people feel that the Bailey type perhaps compromise a bit too much, and whilst they cope well enough most of the time, they struggle when the going gets really tough. That's probably why the modern premium planes tend more to the bedrock, thick casting, thick iron designs.

If you can plane it with a plane of any type, you can plane it with a bailey plane. Most people don't know how to use them, which leads to thinking a thicker harder iron and a heavier plane is the answer for difficult woods (and a higher angle).

There's really nothing to be improved for a user who knows how to use a bailey type plane. It'd be lovely if they could get rid of the metal friction, but that's not going to happen easily with a metal plane.

Premium planes are an improvement for beginners, but the extra weight is a tax after that.

Except for the crowd who does nothing but smooth plane (or better yet, who don't much use planes, but instead sand) - those folks are unlikely to notice much extra weight.

I can't speak to the patent showing three points of contact. It's hard to tell what's contacting what on a cap iron when you are looking at the cap iron setup out of plane tension. Even if I had three points of contact, I'd want the contact to be biased toward the edge as the more pressure there is on the edge, the less chance there is that a chip will get under it.

The sprung cap design does work well with the cam lever cap, better than the modern (un)improved designs that claim to be closer to wooden type caps, but aren't that, either.