Where did the knowledge about the capiron get lost?

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Corneel

Established Member
Joined
19 May 2010
Messages
1,520
Reaction score
0
Location
The Netherlands
I saw in a corner of my eye some discussion about the "loss" of knowledge about the correct use of the capiron, in another thread. And I thought, why not start a new one? It is kind of interesting how these things work in this world.

My interpretation:

The capiron was invented in the 18th century and got real momentum in the 19th century, to the point that almost all bench panes were equiped with capirons (chipbreaker, topiron, double iron). That includes all the woodies, the Baileys, the infills. Single iron planes became rare. Then, after the war (the 2nd WW), the electric motor became so cheap that the handplane became more and more dormant. A hobby woodworker from the 1970's would rather use a sanding attachment on his drill then learning how to sharpen and use a handplane. He would buy his wood in finished sizes from the local "do it yourself" shop in the neighbourhood. I am not too familiar with the trades, but even there I can't imagine a very prominent position for the handplane, compared to the 19th century shops. The result was a decrease in availibilty of new handplanes and knowledge was more and more dispersed to isolated islands. It was described how to use the capiron in every woodworking instruction book, but usually only in one sentence.

Then came the "handtool renaissance", somewhere in the 1980's - 1990's. At the same time the Internet was develloped and enthusiasts gathered together on usenet and later on various forums. The first users of the internet were university people, software engineers came first, then the others. Overall, there were very few real trades people on these forums in the beginning. The typical behaviour of people like that is to diagnose a problem first through thinking hard about it, then do some experiments in the lab (the tinshed in the garden) and then compare the results to the thinking. Literature study showed that the capiron was supposed to break chips and help against teraout, but they couldn't replicate that in their tinshed, so they decided almost unanimously that the caprion was a useless part of the plane and the only way to cope with tearout was a high cutting angle and a really tight mouth. See the rising popularity of the bevel up planes and see how the famous modern infill makers stopped reproducing the antique double iron designs in favor of very thick single irons and see the high angle frogs from Lie Nielsen. On the forums I can only find two names argueing in favor of using the capiron to combat teraout, Warren Mickley who works in the restauration business, and Todd Hughes who was tool tinckerer and trader.

Then came 2012. Let me describe that event from my point of view. I am a hobby woodworker, never had any formal training. I had occasionally trouble with tearout, I knew that the capiron was supposed to help, but never could get it to really work. Setting it close didn't help. Setting it closer only caused a clogged mouth. In 2012 the video from Kato was again made available for the publicum at large. For me (schooled as an engineer, so thriving on numbers) it was an eye opener because it actually contained some numbers and because it clearly showed how it works. It's difficult to measure these things but I fumbled with a vernier gauge and saw that my own experiments didn't get the capiron any closer then 0.4 mm from the edge. So I opened the mouth of a test plane, set the capiron twice as close and it "clicked".

I am sure there have been plenty of people all along who knew exactly how to use a capiron against tearout, but it was kind of lost in the very vocal Internet world of woodworking, it also wasn't teached in the magazines and you had to be a carefull reader to find it in the woodworking instruction books.

So, and now my coffee is finished and I am going to do some woodworking.
 
I first came across cap iron use and tearout in the mid to late '70's. I'm pretty sure it was in a book, a guitar maker instructing to set the cap iron close to the blades edge to prevent tearout. I don't think the knowledge was ever lost but it may have been lost to a lot of people.
 
Maybe he was a one off but Mr Clarke my woodwork teacher in the mid to late 70s taught the importance of the position of the cap iron.
 
That's a great little potted history to accompany my morning coffee, thanks Corneel!

Corneel":3lrykdre said:
The typical behaviour of people like that is to diagnose a problem first through thinking hard about it, then do some experiments in the lab (the tinshed in the garden) and then compare the results to the thinking. Literature study showed that the capiron was supposed to break chips and help against teraout, but they couldn't replicate that in their tinshed
I haven't read a lot from those earlier days of the Internet, is it clear that was it, that they couldn't get the cap iron setting to work for them?

If that's so I have to wonder if, like you did and like I did myself, they weren't setting the iron close enough to the edge. Or, and possibly in combination, if they hadn't properly fettled the leading edge of the cap iron so that tiny shavings would bunch up there.

Corneel":3lrykdre said:
so they decided almost unanimously that the caprion was a useless part of the plane and the only way to cope with tearout was a high cutting angle and a really tight mouth.
I have found this attitude prevailing in a couple of forums and it bothers me greatly since I've read a lot of older woodworking books. And it became very clear to me early on in my planing journey that a close-set cap iron does combat tearout very effectively (along with a freshly-honed cutter and the taking of a very fine shaving of course).

You can actually watch the improved result as you set the cap iron closer and closer while taking shavings from the same board: the tearout becomes less and less and finally, with a bit of luck and a following wind, it disappears entirely. At worst it becomes slight enough that a minute or two with a scraper will deal with the last of it.

What bothers me even more is that many of the most vocal proponents of a tight mouth are using double irons, but will tell anyone who will listen that the tight mouth is the only way to plane tricky woods effectively. Essentially ignoring much older writing on the subject and the physical evidence of surviving older planes.

For me it comes down to this: tight mouth on a single-iron plane, close setting of the cap iron on a double-iron plane.
 
Corneel":lpt8gc6o said:
... see how the famous modern infill makers stopped reproducing the antique double iron designs in favor of very thick single irons..

Probably worth pointing out that the original infills had massive irons (at least 3/16" parallel, but 1/4" is not unheard of) so thick irons in infills is not a new design.

The original infills did have double iron though, as you say.

BugBear
 
Corneel":2gzbllc2 said:
... and you had to be a careful reader to find it in the woodworking instruction books.

Well, Planecraft (C J Hampton) of 1934 has, on page 20:

cap_iron_1934.jpg


So "as close as you can get it", and certainly less than 1/64". Planecraft has always been
a widely recommended "hand tool" classic.

BugBear
 

Attachments

  • cap_iron_1934.jpg
    cap_iron_1934.jpg
    109.9 KB · Views: 2,698
I must confess that my credibility as a historian is about the same as my credibility as a woodworker. I didn't do much more research about this subject then some casual reading here and there.

I think a few people from the early days of the internet woodworking community actually experimented with the capiron, with not so great results. The rest just parroted their comments. Just like in normal society.

And indeed early infill plane irons were thick, just like the wooden plane irons. And now I think about it, the recent history also shows quite a few wooden plane builders using thick single irons with steep bedding angles.
 
I think Schwarz, following Charlesworth was one of the leaders of the "new knowledge"
on chip breakers;

http://www.popularwoodworking.com/woodw ... tally-evil

That would certainly chime with the "2012" date you give.

I seem to remember some buzz about the video on Woodcentral, but can't recall (have to search) the date.

EDIT;

http://www.woodcentral.com/articles/tes ... _935.shtml

links at foot of article are all 2012.

OLDTOOLS was discussing the famous video of chip formation back in 2006!

BugBear
 
I'm sure DW will be along soon to discuss this. It is probably worth distinguishing between "woodworkers" and "woodwork forum users". I am not for a minute suggesting that being a forum user means you are not a great craftsman, but I would hazard a guess that the vast majority of woodworkers do not post on the internet. I inherited most of my woodies from a neighbour of my parents who dies a couple of years ago in his nineties. He was an instrument maker, making lutes, organs, hurdy gurdies and lots of other stuff (as a hobby). He worked exclusively with hand tools (apart from his lathes) and as far as I am aware knew nothing of the "hand tool revival" or of woodworking forums. I don't know how he set his cap iron but his finishes were exquisite.
Paddy
 
That's a bit like saying he was a leader on how to use a screwdriver. It's just knowledge that some of us have known about for 40 years. I suspect there are some people around who have known about it for nigh on 70 years. It makes it sound as though Schwarz/Charlesworth is the return of the messiah.
 
bugbear":e28zbu3y said:
I think Schwarz, following Charlesworth was one of the leaders of the "new knowledge"
on chip breakers;

http://www.popularwoodworking.com/woodw ... tally-evil

That would certainly chime with the "2012" date you give.

I seem to remember some buzz about the video on Woodcentral, but can't recall (have to search) the date.

EDIT;

http://www.woodcentral.com/articles/tes ... _935.shtml

links at foot of article are all 2012.

BugBear

I rather remember Chr. Schwarz as being very dismissive and ignorant about the cap iron pre-2012:

http://blog.lostartpress.com/2007/12/31 ... -tear-out/

Cheers
Jürgen
 
bugbear":2mzt47ga said:
Corneel":2mzt47ga said:
... and you had to be a careful reader to find it in the woodworking instruction books.

Well, Planecraft (C J Hampton) of 1934 has, on page 20:



So "as close as you can get it", and certainly less than 1/64". Planecraft has always been
a widely recommended "hand tool" classic.

BugBear

Thank you so much for posting this scan. I was about to myself. As far as I can tell, this graphic has been in every printing of the book. I own a copy of the last printing, the one underwritten by Woodcraft, and the graphic is identical.
 
"I rather remember Chr. Schwarz as being very dismissive and ignorant about the cap iron pre-2012:"

He should probably have read the magazine which I think was his employer at the time:

Graham Blackburn Steps in for Ailing David Charlesworth

http://www.popularwoodworking.com/woodw ... lesworth-2

By: Megan Fitzpatrick | September 19, 2011

Planing for the Perfect Surface

Graham Blackburn has joined the list of expert woodworkers instructing at this year’s Woodworking in America Conference (Sept. 30-Oct. 2 at the Northern Kentucky Convention Center). Friday, Sept. 30, 2-4 p.m & Saturday, Oct. 1, 4:30 p.m.-6:30 p.m. (2011)

For the perfect surface you need to be able to plane any piece of wood in any direction, regardless of grain. This is what planes are designed to do. Watch as Graham demonstrates the secrets of the cap iron, a jig-free method of sharpening, and the basic user techniques for guaranteed accuracy in order to turn virtually any bench plane — wooden, Stanley-type, or high-end — into the ultimate finishing tool.

Sound familiar?

It's my understanding that the same information is imparted in Blackburn's video series that came out in 2005.

http://www.shopwoodworking.com/woodwork ... kburn-dvds

Cheers,

Charles
 
:D I wonder if we can trace the modern use of the screwdriver. Maybe an article by one of the internet woodworking guru's who discovered the lost art of how to fasten together two bits of chipboard with a screw. Anyone?
 
CStanford":2qdllpxd said:
A tight mouth and a light cut will tame tear out as well, as can be seen here where very deep tear out after machining is completely removed by the hand plane:

http://www.amgron.clara.net/shavingaperture53.html
Fabulous results of course, but very relevant quote from that I feel:
As far as thin shavings are concerned, I think it is a mistake (though a very popular one) to say that the cap-iron to edge distance has much effect on the tearing.
 
Fabulous results do tend to speak for themselves.

The plane offers three direct adjustments that bear on the matter -- cutter projection, mouth aperture, and cap iron distance to edge. The fourth being up to you -- cutter sharpness. I'd recommend paying attention to all four of these, rather than getting caught up in too much hyperbole with regard to any particular one. This is precisely the advice you'll find in Planecraft, Wearing, et al. There is no mystery and there have been no 'new' discoveries. Wearing's Woodworkers Guide to Handtools essentially reproduces, verbatim, the Planecraft chart from BugBear's scan along with appropriate advice about mouth aperture, adjusting the cutter, and honing. All you need.
 
MIGNAL":16pbp6t9 said:
:D I wonder if we can trace the modern use of the screwdriver. Maybe an article by one of the internet woodworking guru's who discovered the lost art of how to fasten together two bits of chipboard with a screw. Anyone?

I'd bet good money a lot of those guys would make a mess of installing a screw - countersink wobbly and malformed, resulting in head too high, head too deep, pilot hole to shallow, too deep, wrong size for the species/screw combination, etc.
 
MIGNAL":3hvgum8k said:
That's a bit like saying he was a leader on how to use a screwdriver. It's just knowledge that some of us have known about for 40 years. I suspect there are some people around who have known about it for nigh on 70 years. It makes it sound as though Schwarz/Charlesworth is the return of the messiah.


I deliberately put "new knowledge" in scare quotes.

As you imply, it's old knowledge, newly re-publicised. As Corneel points out in the first post, it wasn't universally known.

BugBear
 
Back
Top