Crucible dividers?

[Stanley Covington]

They may have been the first to understand before they could be uniters of stone they would first need dividers.

jtk

I once did a hotel project in Istanbul many moons ago which incorporated the ruins of an ancient palace into a modern hotel. At the time, it was a Hyatt, but now its called the Çırağan Palace Kempinksi. I was privileged to watch craftsman working over a year to restore the damaged stone facade, columns, and corbels by hand. They even made bathtubs on the jobsite from solid blocks of marble. The only modern tools they used were handheld circular saws, grinders, and sanders. There was a blacksmith with a portable forge working on the jobsite several days a week reforging/sharpening stone chisels and points for the masons. They used their chisels until they were just nubs.

It's fascinating to watch craftsmen produce architectural stonework neanderthal fashion. While they may have used scaled drawings when planning arches, corbels, columns and arrow slits in ancient times, every assembly, with every stone in the assembly, is drawn full-scale on a wooden floor in a shed at the jobsite using, you guessed it, dry lines, chalk lines, straight-edges, squares (often very large triangulated wooden squares), compasses, dividers, and trammels. No protractors. No slide rulers. No graduated rulers. No tape measures

In fact, scaled drawings are said to have been invented by Filippo Brunelleschi when he was designing and constructing the Cattedrale di Santa Maria del Fiore (Il Duomo) in Firenze, Italy beginning in 1296, the largest dome in the world for centuries. Historians say that prior to Brunelleschi, there was no such thing as architectural or engineering drawings anywhere in the world. No, Leonardo Di Vinci did excellent sketches and drawings, but not scaled orthographic drawings.

From this full-scale drawing on a wooden floor, stone masons fabricated parchment or leather patterns to simulate curved surfaces, and wooden patterns for layout and to check dimensions while cutting with hammer and chisel.

Stone masons were the most educated of the construction trades, were always in high demand for castle and cathedral construction, were often well-off financially, and were one of the few trades permitted to travel freely from jobsite to jobsite and from country to country.

But remember that standard weights and measures are a very recent invention. Prior to that, each area and each Lord insisted on using a different length for mile, foot, cubit and inch (hence the term "Ruler"), and used different divisions of each, so measuring using a graduated ruler or measuring chain was risky. Those old boys may not have know much algebra, but they knew how to measure and solve difficult trig problems with strings, dividers, squares and straight-edges better than almost anybody.

We could do worse than to learn from their example.

[Frederick Skelly]

Great story Stan. Got any pics to share?

[Stanley Covington]

Great story Stan. Got any pics to share?

Not really. This was before digital photography, and my chemical photos are all in storage in the States. But here is a website for the hotel.https://en.wikipedia.org/wiki/%C3%87...C4%9Fan_Palace

[Frederick Skelly]

Man, that's some kinda hotel!

[David Eisenhauer]

I read a novel named "Pillars of the Earth" (I think it was named that) by Ken Follet several years ago that featured a stone mason/builder as the main character and that story referred to the better stone masons as being the main drivers of a large project during the English medievel period. As I recall, there was an amount of description of the main techniques and design thinking of the day included in the prose.

[Gary Cunningham]

I read a novel named "Pillars of the Earth" (I think it was named that) by Ken Follet several years ago that featured a stone mason/builder as the main character and that story referred to the better stone masons as being the main drivers of a large project during the English medievel period. As I recall, there was an amount of description of the main techniques and design thinking of the day included in the prose.

Jack Sharejack was either the mason, or the mason's father. I do remember the Priest was named Waylerian Bygod, or some spelling variation.

[Stanley Covington]

Man, that's some kinda hotel!

Yes, its an impressive hotel in a prime location overlooking the Bosphorus Straits.

I was just a young Project Engineer back then, fresh out of grad school. My employer was both contractor and investor. Lost plenty of money, but then, new hotel projects always do. The third owner of a hotel, after two actual, or near, bankruptcies, usually is the first one to make an actual profit on a high-grade, name-brand hotel.

The stonework in Istanbul is amazing. The crusaders brought home a lot that city's architectural stonework details and incorporated them into castles and cathedrals throughout Europe, where they can still be seen. If you get a chance, you should visit Istanbul before it slides too far back into medieval ways.

[Frederick Skelly]

If you get a chance, you should visit Istanbul before it slides too far back into medieval ways.

It's definitely on my list!

[Patrick Chase]

Y
I was just a young Project Engineer back then, fresh out of grad school.

Hah, I knew that deep down you were One Of Us (tm).

[Edwin Santos]

If I need to layout a tenon or mortise, I can measure the width, split the difference with a divider, and layout centered on a line marked on tenon or mortise or both. Quicker and more accurate than fiddling with marking gauges.

When laying out mortises/tenons on stile and rails, a divider set to the desired height of mortise/tenon will ensure every mortise is laid out exactly. When doing multiple doors, windows, or shoji, the divider can be used to mark the story sticks (vertical and horizontal) used to layout each rail/stile.

When making shoji with complicated kumiko, the precision and repeatability of a lockable divider with a fine screw adjustment is essential. Simple can't be done with a measuring tape.

A divider used properly makes it easy to check for and eliminate accumulated errors. Nothing can do this as well as a good locking divider with a fine screw adjustment.

When laying out legs and backs for chairs, a divider makes it easy to triangulate and mark centers quickly and precisely from a centerline on the seat's center.

When doing trim work, or fitting floor boards to walls or around columns, a divider with a pencil attached (like the Starrett) can be used to scribe cut lines, transfer distances, and triangulate transition points.

And of course, nothing beats a divider for precisely and quickly dividing a line/distance into equal parts.

A divider beats every other tool at laying out angles, halving angles, and locating points on a circle.

There are many other operations that a divider does best. I usually have three dividers, all with sharp points and fine screw adjustment, on my workbench whenever doing layout.

There are a good reasons why the divider, along with the square and plumb, is the most ancient of mankind's tool.

Stan

Thank you. I'm a big fan of non- tape measure, non-ruler layout, and sometimes it's easy to forget and fall back into old ways. That's why posts like yours are a good reminder. When I work with dividers and story sticks, the errors seem to all but disappear and woodworking becomes much more enjoyable.

I'm decent at math, but still, it can be very difficult to accurately divide up a case for equally spaced compartments, drawers maybe, using a tape measure or ruler. Maybe your compartment partitions are 15/32 and the outside case is 3/4 material 31" high, and you need six equally spaced compartments. I can't seem to perform a layout like that accurately with an imperial tape measure nearly as quickly as using dividers with no math required.

They can make installing pulls and cabinet hardware very easy. Especially when you're dealing with a metric on center dimension drawer pull and your tape measure is imperial.

Learning to use actively use dividers and work off centerlines was a game changer for me. Good discussion,

[Dave Anderson NH]

Don't forget boat building Stan. In the days before CAD, boats and ships were laid out with pigs, wooden curved battens, chalk, and dividers in a lofting shed or in the loft. I was privileged to walk up the dozens of stairs in one of the buildings to the lofting attic at the Redmond shipyard in South Shields (Newcastle UK) quite a number of years ago. Chalked curves were still laid out on wooden floor. The curves were transferred to paper patterns and the used to cut the steel. The trick was transferring shapes from the half hull model to the lofted full size chalk profile.

[Pat Barry]

I'm decent at math, but still, it can be very difficult to accurately divide up a case for equally spaced compartments, drawers maybe, using a tape measure or ruler. Maybe your compartment partitions are 15/32 and the outside case is 3/4 material 31" high, and you need six equally spaced compartments. I can't seem to perform a layout like that accurately with an imperial tape measure nearly as quickly as using dividers with no math required.

Hi Edwin, I must be missing out on how you would accomplish this quickly with a set of dividers. It seems like a lot of guess and check and reguess and recheck, etc, spiraling ever closer to the correct answer. This seems like it would take quite some time. I'd like to learn a better way. Can you walk me through your method to accomplish what you outlined as the problem above?

[Rob Luter]

I guess I'm a bit late to this party.....

Nice looking dividers and I'll bet they work very well. I wonder if Crucible is going after the same market as Bridge City? As nice as they look, I have several sets already from my days as a draftsman, and a few more from rust hunts. Between these and multiple compasses, I'm good to go.

[Edwin Santos]

Hi Edwin, I must be missing out on how you would accomplish this quickly with a set of dividers. It seems like a lot of guess and check and reguess and recheck, etc, spiraling ever closer to the correct answer. This seems like it would take quite some time. I'd like to learn a better way. Can you walk me through your method to accomplish what you outlined as the problem above?

Hi Pat,
Here's how I would do it: First, I'd cut a story stick in length exactly the height of my case, in this example 31" but in a moment you'll see it can be anything. If the case exists, then I would make the stick with no measuring by holding the stick up to the case, marking the line and cutting. Then take a piece of the 3/4" material from the outside case and holding it, mark off that thickness at each end of the stick. This now gives us the interior space of the carcase between the two lines we just marked.

I would then take my dividers and open them up to a rough estimate of one sixth of the case by eye. Very rough. Now walk the dividers in between the two lines you made, adjust, do it again until six steps lands you precisely on the line at the other end of the stick. Yes, this is trial and error, but you shouldn't have to do more than two or three iterations, because when you adjust the dividers bigger or smaller a tiny bit it makes a big difference because the change accumulates sixfold, once for each step. Now our dividers are representing exactly 1/6 of the interior case center line to center line. Walk them one last time, pushing in the point at each step to mark the division lines, and then come back with your pencil to mark them. This entire process shouldn't take more than about 10 minutes honestly.
So what if we want to subtract out the interior partitions and illustrate the sub spaces inside the case? In the example, I said the interior partitions were 15/32" material. Take a scrap piece of that material and adjust/set the dividers to half the thickness using the walking method. Then place the dividers on each partition center line and walk once above and below that line to then mark the partition thickness. Now your story stick is a complete vertical representation of the case showing the top, bottom, each partition, and each space in between all of which which should be identical. Transfer all measurements from this stick in the course of building your piece including the drawers (height and width at least), and then label and keep it if you ever intend to build the item again. In this process you have not needed nor reached for a tape measure or ruler.

I hope this makes sense. It's one of those things that's easier to show than explain in words. Often I end up tacking a temporary hook to the end of a horizontal story stick and using it for setting up crosscutting stop blocks on the table saw sled. This is how I was taught, and if there's a better way than the method I've described, please someone let me know.

If the eye method of getting in the ballpark with the dividers sounds too rough, there are two other methods that give you a starting point that will be very close, I can share if interested.
Edwin

[Jim Koepke]

This entire process shouldn't take more than about 10 minutes honestly.

It would surprise me if it takes much more than a minute.

For me it goes faster than getting out the tape measure and doing the math. It is also less prone to error. My errors have diminished greatly since switching to dividers and story stick from using a tape measure.

jtk