The Joy of Sectors: Getting our Galileo on...

"For the eye is always in search of beauty, and if we do not gratify its desire for pleasure by a proportionate enlargement in these measures, and thus make compensation for ocular deception, a clumsy and awkward appearance will be presented to the beholder."   

- Vitruvius, De Architectura 

Of course, a major part of the "rebirth" heralded by the renaissance was a revival of the mathematics and geometries of the Arabs and the ancients. By harkening back to the glories of their Hellenic ideal with their domes and pillars, the Renaissance brought with it a new and almost slavish devotion to finding the sacred in geometry and symmetry. Not just buildings, but furniture and textiles began to push painted, woven, and carved decorations to ostentatious heights.

I'm not particularly well known for being good at math and certainly didn't receive high enough marks in school to give one the feeling I would go on to write fluently about engineering and architecture. Thankfully, our typical renaissance artisan wasn't particularly well known as a mathematician either.

Please note that here I am drawing a line between the theory and the application of maths. Although the loftier theories may have passed him by, the practical maths of proportion and symmetry were alive and well in 16th century workshops. The average Elizabethan joiner may or may not have known who Euclid or Pythagoras was, but he could apply their theories well enough to please the eye and the customer.

We've discussed some basics of dividers before, when we were coopering. Add a sector and by their powers combined, you can accomplish an amazing number of tasks with very little actual number-crunching.

I first learned the magic of the sector in the same math class where I learned about the Fibonacci and the various permutations of the Golden Mean. Then I didn't think about it much for several decades.

Like most woodworkers, I've always kept a set of dividers. Dividers are handy for drawing circles and arcs for those fantastically symmetrical carvings I mentioned, also transferring dimensions from a ruler or a drawing to the wood. I've used them for laying out dovetails and for finding center and a host of other simple tricks.

But when they're accompanied by a sector, they can do much, much more.

My geometry teacher knew that the wickedly-sharp compasses we were equipped with as part of our standard kit were capable of more than stabbing us through our canvas bookbags. When paired with a sector, they could be used to accomplish great feats of proportion and scale

And she had no less a personage than Galileo Galilei backing her up on that.

I didn't care, I was nine; I wanted to draw circles and stab ants with the damn thing. Education is wasted on the young. Sometimes, I think adults should be required to repeat primary school periodically to pick up all the sharing and math and social studies that we missed, never mind the history. We seem so determined to keep repeating our history anyway, it might as well be in a classroom.

"I'm sorry, boss, I can't come in today, I have geometry class and then detention because I said I was thinking about voting for Donald Trump..."

Anyway... flash forward to a 2011 issue of Popular Woodworking magazine I picked up at the newsstand because of a cool cover article about Thomas Jefferson's stacking bookcases. Inside was an article by Jim Tolpin on the use of the dividers combined with a sector (see the video below) to derive a host of useful proportions and measurements for cabinetry design.

Like my teacher before him, Jim attributed the invention of the the sector to Galileo. I'm a big Galileo fan, going way back, and ere the end of things, we might even get into some of his experiments with optics because I enjoy that sort of thing.

Galileo's Sector displayed in the Putnam Gallery -- Image via Wikimedia Commons, Creative Commons CC-BY-SA 3.0

They were both likely wrong about the inventor. The basic principles were first proposed by Euclid and put to various uses since. It seems more likely that he was the Bill Gates or Steve Jobs of the late Renaissance. He was a technological entrepreneur who envisioned new and popular uses by combining existing technologies and concepts in unique ways. That said, who initially turned a compass into a more complex instrument matters little, because ere the end of the 16th century, the concept broke out in a Big Way in the manner that technological leaps always seem to.

The sector as Galileo created it is partly well known because of who he was, and partly because it was enormously successful as a commercial product. The sales of the instruments made his fortune long before he started tweaking the beards of the Inquisition with his planetary models.

Galileo primarily sold his sector as a military tool, an instrument which in addition to its more basic Euclidean functions carried additional scales useful for the gunner in the trenches.

I have no use at the moment for determining powder loads and trajectories. There just aren't that many armies out there right now that need that sort of thing done the old fashioned way. I will be making a simpler, significantly less schmancy, workingman's sector along the same lines as Jim Tolpin's.

If nothing else, I have a lot of period carving and surface decoration on my project list, so we can look forward to seeing great granddad's dividers and sectors come out for that.

And for now -- since sectors weren't all that widely used until the 17th century anyway -- that will be the soft limits for our use for the things. I'll make a couple in different sizes and we shall see what use can be made of them without gunpowder getting involved.

That said, the Honorable Artillery Company was knocking about, but they weren't really what you'd call a trade guild. Nevertheless, I picked up a copy of Galileo's instruction book that was sold alongside his sector because you never know when you might need to hit something a long way away with a ball of something fired out of a tube full of grey powder.

- Scott

Drafting patterns for leatherworking

Note: This post isn't really about 16th century methodologies.

I've shared a few of my favorite "hacks" (as the kids say) for making leather items with a bit of improvisation in the tools department. We've used flower pots to build mugs, we've used butter knives for skiving, and my favorite cheap woodworking chisels for cutting.

So let's talk about pattern making.

If you've ever followed my maskmaking tutorial or done any other leatherworking without a pre-printed pattern, you've noticed that there's often a size discrepancy between any paper pattern you've created by wrapping the item in paper and marking seams (as we did with this shoemaking post) and the leather you're going to use.

This can cause some real fit issues.

The problem stems from the difference in thickness between paper and leather, combined with the fact that paper doesn't stretch around a form and leather does. You could use some math to account for the thickness, but the stretch is a bit more difficult to guess at, which can result in some wasted materials.

Here's my Not Even Remotely Period (NERP) approach to leather patterning that saves me a lot of time and leather when I'm winging it with a pattern: craft foam.

In the image below, I am preparing a knife sheath for one of my carving knives. I've wrapped the knife in paper and marked the seam, but to get a better handle on the actual shape of the final piece of leather, I made the pattern in the back on thin white foam which I purchased from a local Michael's craft store.

It's not quite as thick as the final leather, but it's close. More importantly, it stretches a bit in a manner that is very reminiscent of damp leather. And since this is a pattern where the fit is precise and the seams have to just meet with no seam allowance, fit is so very crucial.

It's NERPy, sure, but it works a treat.

- Scott

Now What? The evolution of the project...

Today is December 1st. The state of the project? It is to laugh...

I've been very sick since the end of September. I have this stupid... thing that happens to me periodically. Around here, we call it Sporadic Lego Head Holiday Syndrome. We call it that because it's apparently un-diagnosable by modern science. Perhaps the dumbest assumption I made at the beginning of this year was that I'd be able to stay healthy for the entire year so that I could complete the rather daunting task list I'd written for myself.

All that is somewhat beside the point.

The brief interstice moments the past couple of months, I've spent working on our kitchen. Because family comes first and I keep my promises to others before I keep the ones I made to myself. So I have a functioning kitchen and a non-functioning artisan project...

I'm proud of the work I've managed to finish on the kitchen, but the "One Year Mission..." part of this blog has not fared nearly as well.

Have I failed? 

It would be difficult to argue otherwise. I certainly can't knock out two dozen trades in the one month I have between now and January 1st. So it would be pretty stupid for me to say I haven't failed at my original mission.

If you feel the urge to say I told you so, please feel free to swallow that urge. Seriously. Don't be that person.

The truth is, this project was beginning to morph into something more long-term long before my head swelled to cartoonish proportions. If I'm honest with you and with myself I began to second-guess the format I chose for this back in August when I experienced the true difference between learning an aspect of a trade and truly practicing it.

Of course, it's impossible to practice 111 trades from 54 guilds at once.  There are valid reasons why tradesmen specialized and it wasn't only because the guilds required them to. The requirements for specialization forced them to focus on a single trade and operate at the top of their game.

So now what?

Yes, I am a craftsman, but I am first and foremost, a storyteller. So I will finish the story.

This story has grown in the telling, as stories are wont to do. With every blister, splinter, burnt loaf, and failed thimble, it has become about more than the making of the stuff and less about the making of the artisan. For the past year, I expended too much effort on the tasks and not enough on the tradesmen.

A story like this deserves all the space it needs to tell it properly. It deserves more than scene setting, it deserves character development. I don't rightly know how that will look, but that's what I plan to do. So my continuing mission is a purer, more thorough version of the original one, but without the artificial time constraint.

I said at the outset that I had a problem with how history is taught, with the People Magazine approach that is a pointless litany of glittering celebrities carrying on, mostly behaving badly. It's no wonder that students view history as a list of dates to be memorized and the names of kings and generals to regurgitate. I found myself doing the same thing on a different level, ticking off a list of items to make and move on to the next.

Material culture is only interesting in how those materials reflect the culture. The tools are only interesting in the way that they reflect their user and their maker. I lost sight of that as I focused on the sprint.

Spending three weeks in the smoke and flour dust of our ersatz renaissance bakery showed me how thin my understanding of these trades was. How superficial the project had become, mostly because I had set an artificial deadline that made it look more exciting from the outside and forced it to become less in-depth on the inside.

By failing, I've set myself free from my own constraints. There's probably a deeper metaphor there for those who have an urge to mine for such things.

In the meantime, I've a story to tell. I invite you to stick around and help me tell it. If you don't, I certainly understand.

~ Scott

Turn Turn Turn, for everything there is a cliche, turn turn turn...

I apologize for my absence. I've been having a... thing. I don't believe in writer's block so it's not that, it's just... I dunno. You can read about it at Pages to Type if you want: Dumbo's Feather Revisited: Of writers and rituals otherwise, accept my apologies and let us move on to wood spinning in a circle with a blade placed against it...

The Worshipful Company of Turners

My lathe. Up close and personal...

I've never particularly liked turning. Modern lathes are fast and dangerous and freakishly expensive, which combined uncomfortably in my mind with the idea that has often been pushed on me that all woodworkers are aspiring turners.

I am not.

At least not until I discovered that I could build my own lathe, which appealed to my "Make Neat Things" aesthetic and helped me take my first hesitant step onto that slippery slope of wood turning.

The history of lathes is very interesting and rather closely parallels the history of the spinning wheel and the pottery wheel, all of which operate on much the same principals, though not necessarily in the same plane. By the 16th century, there were three kinds of lathe existing side-by-side: the fairly primative bow lathe, the springpole lathe and the treadle lathe, which I gather was a recent invention.

Almost anything that was round in Elizabethan England was turned on a lathe. Even if something was cast, the pattern from which it had been cast was probably turned. Patternmakers love wood and they love lathes.

My old nemesis/muse Jost Amman, of course, has a turner depicted at his trade. The lathe isn't well depicted, but you can just make out the springpole coming across the ceiling and the strap or string that is driving the sphere (apparently) that the guy is turning.

The turner at his trade from Jost Amman's "Das Standbuch" of 1568

I admit I'm curious about why he'd be turning a sphere. If anyone knows, leave a comment. If that's a bowl, he has it on the lathe sideways, but an engraver can't necessarily be expected to accurately depict the nuances of every trade, I suppose.

My lathe was built on the same basic plan as this one I found on Pinterest. I made the heads from two sharpened carriage bolts, which I carefully and painstakingly aligned to give a nice, flat spin for the workpiece.

The string started out secured to the springy limb of a pine tree, a suggestion made by Peter Follansbee in one of his videos, but I confess that I eventually swapped it out for a four-ply bungee rope when I got tired of being whipped by the tree for my temerity. 

Problems to Solve

As you can see from the image below, my oak billet (I'm starting small, a handle for a socket chisel) was chattering something fierce. This happens when the blade of the tool skitters across the work surface rather than biting into the wood as it is supposed. I suspect my lathe tools weren't as sharp as they needed to be in spite of my hours spent honing them. I shall return them to the whetstone again tomorrow and finish off with a good bit on some emery paper and then leather stropping.  

All else being equal, this shouldn't be happening.

Another thing I've decided to add to the design is a drive wheel. I got this idea from an article written by Roy Underhill, who explained that the diameter of the piece affected the speed of the turn. So I sat down with a bit I cut from one end of an old maple rolling pin and milled out a pulley, essentially. The trio of spikes will (theoretically) go into the small piece to be turned and drive it at a higher rate of speed. 

The concavity of the drive wheel should keep the string from creeping, which has been a bit of a problem already.

To compound my sin with the bungee, you can see that I began with a length of nylon paracord that I had lying around. It has abraded with a vengeance and I've already had to deal with broken lines and splicing new bits of line into my machine. 

I will be replacing the paracord as soon as I can with a proper bit of line, hemp if I can find it.

Once I have things worked out and in working order, I will get on with the real task, turning a small wooden bowl like the ones found on Mary Rose. But we're nowhere near there yet.

More to come.

- Scott

Late addition: 
Foot-powered lathes at The Woodwright's Shop with Peter Follansbee and Roy Underhill. Enjoy!

Watch Wretched Ratchet Reading Rack on PBS. See more from pbs.

And then my brain tried to kill me... The state of the project.

The other day on Facebook, I promised to update soon. I promised that I wasn't dead. And because fate has a warped sense of humor, then my brain tried to kill me.

Like it often does.

So... lots to catch up on. Coffee, for instance. Haven't had any coffee since Wednesday and I have a lot of catching up to do. Also there's a kitchen sitting around in pieces that needs to be reassembled so we can, you know, cook food and stuff. Tiling and cabinets and countertops and miscellaneous whatnot await me, but coffee first. 

Because priorities, I have them.

Which brings us back to this project, and most especially this blog, which I have been neglecting, I fear.

I seriously underestimated the toll that accepting a full-time job would have on this project. Especially with all the home renovations that have to be done. The level of organization necessary exceeded my ready supply of tools.  I'm not really good at organization on this scale at home. I do fine at work, juggling huge projects that span entire years, but when I get home... something clicks off in my brain.

Just one of the many ways my brain periodically demonstrates how it hates me.

There's a horn out in the shop that's halfway to becoming a beaker, a half-made bow-lathe that needs some attention, and all the makings of a woodfired oven stacked under a tarp waiting for a dry spell so I can call out the troops to come help build it.

Anyway, I talked to the engineer, and we're trying something new.

Because real, bought and paid for, life trumps blogging projects, the bulk of my time is spoken for. There's just no way around that. Some of what I have to do for the kitchen (tile for instance) will align with parts of this project, but most of it is too modern to fit neatly into Renaissance Artisan business.

One or two days a week, however, will be devoted entirely to this project. Building, experimenting, photographing, and documenting (cough-blogging-cough) will take precedence on those days. We're still working out which days and how, but that's the plan or this is never going to work out.

Like the Facebook thingy said: "one man, 54 Livery Companies, 111 trades, 52 weeks." And we're at the end of week 18. At this rate, it's never going to work and before you propose it, I am not yet willing to entertain the idea of cutting projects. Part of the "fun" of doing this is figuring out how to do it without neglecting the day-to-day of modern life.

Anyway, that's the state of the project.

More later. I have coffee to drink and all the aforementioned projects aren't going to get closer to done by typing.

~Scott

The Man with Three Bottoms: Making a Mary Rose Tankard Part Three

When I get stressed, I make things. Yesterday I made mistakes. But they were 100% lovingly hand-crafted mistakes, so at least I have that going for me...

Incidentally, if you ever want to try doing this, a book I recommend that you get your hands on is called "100 Keys to Preventing & Fixing Woodworking Mistakes" by Alan and Gill Bridgewater. There are probably a thousand books like it, and you're going to need at least one.

Just trust me on this.

Bottoming Out

I've been hunting around online and even reached out to the Museum of London and the Mary Rose Trust, but nowhere can I find a decent image that shows the bottom of one of these tankards. So I am going to have to guess.

I don't know if you've ever taken a good look at a bucket or barrel, but the bottoms sit in a groove called a "croze". Professional coopers have a special tool for cutting the croze into the barrel end which I do not posses, so to avoid making yet another tool (delaying completion yet again) and/or defaulting to my power router, I had to mark a line and cut the croze by hand.

The marking gauge from grandpa's toolbox is ideal for this. It has two sliding rules that I can set to separate depths. To scribe two lines at two different depths (the top and bottom of the croze in this case) all I have to do is set both pins and spin it around to make the second one.

As you can see, I've had to temporarily put the tankard together using cable ties. These are obviously not correct for the period, but a period cooper wouldn't need to do this step so I suppose I'll get over it.

The croze is, essentially, a dado, which is to say a groove in the wood to accept another perpendicular piece, the bottom of the tankard in this case. Incidentally, if I ever make more of these on a more generous deadline, I shall make that croze plane. Cutting an accurate dado on an inside curve is not something I care to make a habit of. This vessel is rather smaller than most antique croze tools I've seen, so I'll have to make it from scratch in the shop, hence skipping it this time in the interest of time.

So far so good. I was feeling pretty good about how things were going and forgot what Indiana Jones warned about Holy Grail about when things were going well.

"That's usually when the ground falls out from under your feet."

Bottom #1

The concept is simple. A piece of wood is cut into a circle and the edge narrowed to be wedged into the croze, forming a seal. In a barrel, this is called the 'head', as in the saying 'cash on the barrelhead'. I had a large piece of tulip poplar lying around and used a coping saw to cut out a circle. Then I used chisels to cut a dado around the edge to slip into the croze.

It's not as messy as it looks in that picture. Honest. I was mid-way through the endless attempts at accurate shaping at this point. It didn't even pretend to fit. And as I whittled away more and more of the poplar, it just got worse.

Finally it just fell out and I left it lying on the grass.

Bottom #2

The problem as I ascertained it was that because I didn't use the proper tool to cut the croze, the shape was not actually a perfect circle. I paused in my operations to clean up the croze and get a better handle on their actual inside shape. It turned out to be sort of a rounded octagon.

I took the last bit of poplar I had and used a handsaw to cut it into an octagon to better echo the interior shape of my tankard and then went back at it with my chisels.

The paring and whittling and chiseling and cursing went on for quite awhile before the wood split and I was left holding two bits of wood where only one should go. I was running out of daylight and poplar.

Time to switch woods and tactics.

Bottom #3

Pine. It was all I had handy that was wide enough to cut a bottom out of and I was tired of wasting better wood on a learning exercise. Get a working bottom done, I decided; then you can use it as a template to cut one out of good stuff.

You know... what I should have done to begin with. Pride goeth before the autumn and it was darn well time for spring.

More later after I sort this out...

~Scott

Thimbles: Reloaded

So the consensus opinion here and on the Facebook page is that annealing the brass is the cure for most of my ills.

I really should have thought of that. You may remember when I mentioned that the difference in stiffness between the modern wire and the 16th century wire for pinmaking was the result of work-hardening because of the way that their wire was drawn as it compares to the modern methods of wire drawing.  The folding of the metal in the 16th century style combined with the effort involved in forcing it through the die stiffened the crystalline structure of the metal.

Caple says that in order to wrap the heads, they had to anneal the wire first because the stuff didn't bend.

It's much the same problem with modern brass sheets. Brass, like all sheet metal, is rolled out to the desired thickness in a machine press that compresses the brass between massive wheels. This has the same effect as drawing wire through a period die.

In my sheets of brass, the crystalline structure is aligned and as stiff as it gets. In order to get more play in the metal, I need to excite the molecules by heating the brass and mess up that crystalline structure once more before it will ever suffer the hammer.  It's much the same as doing anything with iron.

The plan for today is to go out and get a thicker piece of brass and then heat it to a dull red heat using a propane torch and work it from there. I have high, cautious, hopes.

Thanks to the Wayne at Leatherworking Reverend, Louise Pass of Woodsholme, and Andrew Williamson for their advice on this.  I'll let you know how it goes!

~Scott

Sidenote: Because it's been so long since I was in high school metal shop, I looked it up online to make sure there wasn't anything I've forgotten.  All of the sites and videos on brass annealing are dedicated to the community of people who reload rifle shells.

I suppose it's the same thing, except my thimble won't explode if I do it wrong...

"So Sybil says to Marjorie, 'Well we didn't want you to come to the quilting bee any way!' and you know how Marjorie gets. She says 'I'll come to that quilting bee if I..."
ka-BOOM!! 

(Fade to black)

(Voiceover) Has this happened to you? Are you the victim of an reloaded thimble? Call Calvin & Hobbes, attorneys at law...