by Dean Beeman
Rigging needles. I use two types- the “big eye” and the twisted steel beading needle. The beading needles are much easier to use on small diameter threads.
Saw (draw) blades. Fine (54 teeth per inch) and medium (40 teeth per inch). You’ll need both.
Blade pack. I rarely use anything but X-ACTO #11 blades and I buy them in bulk. This pack of fifteen might last for years or for weeks.
Knives. I keep two of them on the table- the one on the left always has a clean, sharp blade, and the one on the right (red paint) always has a used, not-as-sharp blade for applying glue, breaking out pieces, cutting paper, etc. The red one is the one I use when I know that I’m about to wreck a blade somehow.
French curves and pattern templates. The curves are indispensable.
Dividers- Map (rough) and student (fine). You can’t transfer or repeat any measurement accurately and repeatedly without them.
Beeswax. Handy for preventing lint on cotton line, but indispensable for creating a release when gluing.
Forceps. I also use hemostats, but this is my go-to pair.
Compass and Angle rule. Both very handy. Both are worthless for tiny angles and tiny circles.
Hand gouge (chisel). Indispensable for breaking glue joints, I keep this razor-sharp, because it comes in handy as a cutting/punch tool as well.
Rigging scissors. Cuticle scissors, suture-removal scissors and optical surgical scissors. Each is valuable for a particular rigging task.
Large toenail clipper. The flatter (or convex) the better.
Large T-square. For squaring cut card stock. We’ll be using a lot of card stock, and I like to keep my scrap square.
Calipers. I still use the plastic one for very rough measurements, but a digital caliper spoils you for any other type.
Miniature linemen’s pliers. Also, a heavy wire/rod cutter. The flat face comes in very handy for breaking pieces away (mistakes) once the glue has set.
Pin Vises. I use the pair because I usually drill a pilot hole before I drill a finished hole. These have bit storage in the handles, so you can’t see my drill bits. I suggest you start with a standard 20-bit set (#61-80, You’ll quickly discover which ones you break, lose or otherwise need- buy a few of those at a time and store them in a secure place. In my case they’re in the handles- one for 1mm and smaller and the other for larger.
Oriental (decorative) toothpicks. I forgot to put these on the table, along with bamboo skewers. Indispensable for gluing, making small parts, etc.
Paint Brushes. I didn’t include my paint brush collection because it might depress you. I’ve cut off handles to make spars, used junk brushes to apply glue, and generally destroyed many of them. And you’ll have to decide what brush material works best for you. I can say that you’ll eventually need brushes down in the 00 range for detail work- in this case buy the best brush you can find. I have about 4 brushes that I care about, and the rest were purchased as sets (and I probably kept one out of every set and wrecked the others).
The very small tools go into a large tackle box that also contains hundreds of little gil-guys, pieces and parts. If it’s very small or very large and isn’t used often it goes there. Everything else goes into a rotating divided hexagonal thing that I found at a garage sale. Whatever it once was, it’s perfect now.
Let’s discuss the large sanding wands. I make these out of wooden paint stirring sticks (paddles). By applying contact cement to the stick and rough (60 grit) sandpaper to the wide and narrow edge on one side and finer (120 grit sandpaper) to the other two sides I have an easy-to-find tool that is also handy for everyday use. Simply cut a piece of sandpaper to a slightly larger width than the stick, apply contact cement to the paper and the stick and when it’s ready, fold the paper onto the sick. Use a sharp knife to trim the bare edges: this is now a huge emery board and a very accurate straight-surface sander. It will be a great loss if these paddles ever disappear.
At the extreme, these paddles are made from clear (knot-free) pine. They are very exact, well-made and free, but getting harder to find. (I’m guilt-free because of the small fortune I’ve spent on house paint.) They are very handy for drilling and other experiments- as a matter of fact I think it might be fun to build a complete model from a single paint paddle.)
Note that the work board I use is about 18”x24” from a piece of scrap ¼ inch balsa-faced plywood (generally available at home stores). It has many holes drilled through it that act as holding dogs, a cutting and clamping fence and has rounded corners. The balsa accepts things like pins and knife blades while the plywood ensures a flat and, when needed, rigid frame. (This board replaced my earlier one that I made from a sheet of birch veneer plywood. On that one I had glued (contact cement) a 1/8th balsa plank in front of the cutting fence. It worked well for about 20 years until I found the balsa-faced plywood.) If you look closely, you’ll see that I’ve covered the area in front of the board with 1/64th aircraft plywood because it has gotten so chewed up.
A very important feature of any work board is that small cutting and clamping fence. Mine have either 90- or 45-degree angles cut into both ends and they’re the right size for any number of cutting and clamping tasks that require a sturdy brace and guide. (The 90 is on the able. They are screwed-in from the back) The holding dogs (holes) elsewhere on the table are used when the fence is not the right size or shape- dowels or other things can be stuck into the holes to hold odd shapes or an entire model.
This size fits between the arms of a comfortable chair and goes wherever I feel like working- including outside on a nice day. Also, trying to work at a heavy traffic location like a dining table can be a domestic disaster unless you can move all your work all at once.
And keep in mind that even the right or most expensive tool might make the job easier, but not better.
I built this model using scraps that I had in my inventory. My advice is to build one of the other models first, and you’ll wind up with enough scrap to build it.
Another note about tools, methods and materials. I’m assuming you are building this model after either building or reading the texts on at least the whaleboat. If you’re jumping in at this point you’ve missed such subjects as sanding wands, marking, drilling, materials, etc. So, if you come to a step where the process seems to appear from left field, the reason lies in a prior base of experience, processes and materials. You may be well-served in these cases to go back to the beginning and perform text searches in the earlier books. I may get to an annotated index someday, but that isn’t today or tomorrow.
Looking at the sketch of this model, the math leads to the task of drilling about 330 holes that will be filled with a like number of pegs, spokes and axles. Compared to building a large square-rigger that’s a small number of holes (unless you cheat.)
If you go back to the tutorial on how to drill an accurate hole, you might decide that a major risk in building this model is finger cramps. The older I get the less that risk appeals to me, so I’m using a micro-drill chuck (that you probably noticed in a photo from the Higgins Boat.)
Or if you tune into some breathlessly-narrated game of golf, or your team isn’t playing until Monday night you can relax in an easy chair on a rainy Sunday afternoon and drill away with a pin vise.
That’s my excuse for adding a cordless screwdriver and a micro-chuck to the Tools list.
Next up are the materials.
By now you know that I have at least a square foot of leftover aircraft plywood (from the Higgins Boat) and scrap pieces of mahogany and basswood slab (the Honey Fitz).
I also have a scrap of Bolivian rosewood. (Unlike rosewoods in the Dalbergia family that have been fairly-well timbered to extinction, this family- Caesalpina- is more or less a weed.) So that wood is going into the mix simply because no sane person would build a rosewood boat.
And some brass rod, brass tubing and pad eyes. From the display cases that now protect those models I also have leftover acrylic pieces. My objective is to exhaust my inventory o
f this stuff (scrap).
That’s my excuse for deviating from the materials that I’ve noted in the online photos of other versions of Da Vinci’s paddleboat. These, by the way, make an honest attempt to create a model of a boat. (I think I’ve exhausted my observations regarding fool’s games.)
The Template
In this series, we’ve built templates for drilling, cutting and, in more than one case, logic.
To build this model (and to drill those holes) we’re going to need a template that’s a bit flexible. Or invest a few thousand dollars in a computer-aided laser. I’m going for an investment approaching zero.
First, I’ve created a master hole-drilling schematic. This is very similar to the earlier, but crude, layout of angles and shapes:
Note that I’ve added two marking (and drilling) intersections to the first drawing. I’ve also superimposed the smaller (40-degree) pattern onto the larger pattern.
At whatever scale you choose, the drilling dots on the smaller circle have a radius on-center that is ¼ the length of the radii in the inner portion of the larger circle. Geometry being what it is, the circumferential distance between those dots equals the like distance between the intersections of the inner circle.
In other words, the gears should mesh.
To get these to scale I had to print a full-sized (letter paper) copy using a 3x5 setting on my printer. This is a waste of paper, so if you can print this schematic otherwise then have at it.
I cut out the image of the larger wheel and used a school glue-stick to paste it to an acrylic scrap.
A few holes later the template assembly looked like this:
Now things get a bit dicey.
I’m going to build the larger gears first.
I’ve used spray contact cement to create a sandwich of rosewood veneer and aircraft (1/64th) plywood., 1/16th basswood and another layer of plywood. To keep the expensive wood from shredding I’ve soaked it with a heavy coat of clear nail polish. (Any thin shellac should work.)
Once the piece dried, I scored it (lightly) with a circle cutter to a 25mm diameter. Since my circle cutter is intended more for veneer or paper, I followed its trail with the sharp knife and then cut and chipped it to a reasonable radius.
With lots of acrylic scrap from the model cases I constructed a small, clear template. The drilling pattern isn’t obvious without a few centering pins:
There are two drilling guides in the template. The first (next to the black pin) is about 1mm from the straight vertical edge and about 2 mm from the bottom edge. The second (the rid pin) is about .5mm from the vertical edge.
The centering hole (the yellow pin) is drilled in the wheel blank. That pin can slide up and down on the vertical edge to accommodate any sized wheel while maintaining a constant space for the gear teeth.
Now it’s just a matter of creating round wheels. Going back to the other models, I used the scored center to drill 1/32nd holes, chucked the wheels into a beat-up Dremel tool, and sanded a set of 4 wheels to a uniform diameter of 23mm. Here is the entire setup:
A completed gear with holes for teeth, axle and spokes is right dead-center. A roughed-in wheel is in the rotary tool. A rounded wheel is in the template with a card stock spacer to hold it securely while it’s being drilled. The rosewood blank and the circle cutter are ready to create another rough wheel.
While there may be some serious paragraphs in this series this isn’t one of them. You can make the template and the wheels out of whatever you have on hand. The drill size is a function of whatever axles, spokes and gear teeth work for you. Any circle drawn on any piece of wood is just as good as the circle cutter, and however you do it, spinning a rough circle on any axle will create a perfect wheel.
The small cage gears come next, and at the size that I’ve chosen we’re back to the tolerances of wood and its fibers.
After some time spent destroying various combinations of woods and plastics, the best combination of woods came down to a thin sandwich of 1/32nd mahogany and aircraft plywood.
Using the earlier diagram, I created another acrylic (clear) template with 1/32nd holes as guides. I then used a 3/8th leather punch to score the wooden blank.
After centering the template on the scored circle, I drilled the center and used pins to hold the center and the outer holes as I drilled the final pattern in the wooden blank.
I populated that circle with brass rod scraps, fitted the punch back over those guides, and drove out the wheel. That wheel came out like this:
If you started at the beginning of the series, we’re back to equifinality. This process worked for me.
Since I now have the unpopulated drive and intermediate gears, it’s time to get serious about the concept of a base for our machine. I’m going along with guidance and shaping it like a boat.
I’ve laid out a boat plan that bears some resemblance to Da Vinci’s sketch on card stock, and school-glued it to a base. 3/16th pegs will have to serve for posts until I can get the 3 axles working. I’m not providing scale or measurements yet- these will fall out of the prototype. And I encourage you to use a different (better) method to lay out the base and hubs:
I populated the small gears with 1/32nd brass rod, using the face of the small pliers as a spacer. After inserting most of the spokes, I applied dots of thin (10 second) CA to each hole and spoke. The CA wicked into the joints and created a very strong assembly that I trimmed with the nail clippers and filed down to form smooth outer faces:
Looking at the sketch of this model, the math leads to the task of drilling about 176 holes that will be filled with a like number of pegs, spokes and axles. Compared to building a large square-rigger that's a small number of holes (unless you cheat.)
So, if you go back to the tutorial on how to drill an accurate hole, you might decide that a major risk in building this model is finger cramps.
I'll be using tools that I haven't mentioned earlier:
-A 5/16th leather punch. This is optional- you can create the same small circle cuts by roughing-in a circle and turning the pieces on a rotary tool or drill.
-An X-Acto circle cutter. Also optional for the same reason.
-A micro-drill chuck for a cordless screwdriver. Also not needed, but handy for quick tests of prototypes.
Next up are the materials.
By now you know that I have at least a square foot of leftover 1/64th aircraft plywood (from the Higgins Boat) and scrap pieces of 1/32 and 1/16 mahogany and basswood slab (the Honey Fitz).
From a collection of small veneer samples, I also have a square of what I believe is chestnut burl (unbacked) and a scrap of rosewood veneer. A little homework on Italian hardwood production and Da Vinci's early life and career might be helpful here. (If I were to build an exact model I'd substitute chestnut and beech for basswood and mahogany.)
A #80 x ½" miniature machine screw with nut and washers. This is the mandrel I'm using to turn the larger wheels.
One length of 3/16 square basswood and whatever you choose as a 3 ½ x 6” base.
Some brass rod, (1/32 and 1/16) and brass tubing with those inside diameters that will sleeve the rods.
4 brass pad eyes.
From the display cases that I've built I have a bunch of small leftover acrylic pieces that I'm using to create templates. Any clear plastic will probably work just as well
And a small scrap of thin leather.
Keep in mind that we're building what Da Vinci envisioned: a machine that will fit into a boat. Any old boat will do if you want to go that route.
The Model
In this series, we've built templates for drilling, cutting and, in more than one case, logic.
To build this model, we're going to create templates that are a bit flexible. (Or invest a few thousand dollars in a computer-aided laser.) I'm going for a monetary investment approaching zero.
As a guide, I've created and I'm building from a master schematic. This is based on the earlier discussions, and will print on standard letter-s
ize paper:
Construction
It may be difficult to see them until the page prints, but I've added drilling points to the smallest circle. I'm using that cage gear to dictate the circumferences of the larger gears simply because it's the most difficult to get (more or less) right.
At whatever scale you choose, the drilling dots on the smaller circle have a radius on-center that is ¼ the length of the radii in the inner portion of the larger circle. Geometry being what it is, the circumferential distance between those dots equals the like distance between the intersections of the inner circle.
In other words, the gears will mesh and the wheels will turn. That does not guarantee that our machine will operate
In the other models, a photographic flow seemed like a good idea. For this one, all you really need is a picture of the tools and templates