Vicknair Restorations, Vintage Watch Repair and Restoration Weblog: Handmade Watch #2

My second watch is a bit more ambitious of a project than the first one. Like the first one, the movement is based upon the Omega 266 but there is little left of it. It is a regulator display (hours, minutes and seconds separated) with jumping hours and a hacking (stop seconds) function for the seconds display. The jump hours and hacking device are of my own design and, like before, everything is made by hand (my hand), from raw material to finishing and plating. The jump hours mechanism is built directly onto the main plate in order to minimize the increase in height, versus making an add-on module. It is housed in a stainless case made in the classic Calatrava style, 39 millimeters in diameter.

This post will be very heavy on photos (to silence the naysayers before they can speak up), so settle in.

PART 1: Making Parts

3/4 Plate:

We'll start with the making of the barrel and train bridge, which I decided to combine into a 3/4 plate. It is made from .125" thick 360 brass sheet. Most of the tools used in the construction of these parts were also made by me, including the sensitive uprighting drill press seen in the photos (which I will detail in another post).

Locating the steady pin and screw positions and cutting the screwhead counterbores

Turning the stock for the steady pins

Pilot drilling the train pivots

Turning the plate outside diameter

Turning the plate's thickness

Cutting the gear train pockets

The ratchet wheel pocket was also machined on the lathe

Cutting the well for the transmission wheel, which required annular cutters of two different diameters and a face cutter with a hollow center that would leave the center post standing. All cutters are shop-made.

Removing the balance wheel segment

The area around the escape wheel pivot is still rough

Machining the radius of the escape pivot

All of the inside corners are hand filed to remove the corner radii left by the milling cutter.

Machining the plates for the clickspring (the making of which will be detailed further on)

The pocket for the balance cock is cut away.

Reaming for the barrel arbor. The reamer is shop-made due to the non-standard diameter of the Omega 266 barrel arbor.

Face cutting to establish barrel endshake

Machining for the keyless works with cutters I made specifically for the job.

That about wraps it for the 3/4 plate (finishing will be detailed later), so let's move on to the balance cock, which is made in much the same manner as the previous part.

Balance Cock:

The 3/4 plate machined to accept the balance cock

The blank material fitted to the contour of the plate

The screw hole is piloted and the steady pins are made and installed.

Cutting the screwhead counterbore

Machining the rough thickness

Piloting the balance pivot and hairspring stud location

Cutting the counterbore for the Incabloc

Machining the underside, while leaving material around the hairspring stud location

The hairspring stud is triangular, which means that the hole must also be triangular. This was accomplished by the use of a handmade triangular broach, which was pushed through the pilot-drilled hole. Notice the matching diameter pilot on the end of the broach.

The shape of the balance cock is roughed out

Reaming for the Incabloc

The bevels are established by hand after shaping the balance cock

Perfectly upright

Clickspring:

The clickspring is next. It is entirely filed by hand from 1095. The loop in the finished spring isn't ornamental but is a way of packaging a longer length of spring into a given space. As is common knowledge, all other specifications being equal, a longer spring is softer (has a lower rate) than a shorter one, hence the loop.

For a brief explanation of the particulars of different spring types, see here:https://vicknairgunsmithing.blogspot.com/2020/03/spring-has-sprung.html

Drilling the screw and steady pin holes and cutting the screwhead counterbore

Drilling the 3/4 plate for the screw and steady pin

Tapping the screw hole

Ready for heat treatment

After heat treating and repolishing the clickspring, the steady pin is pressed in place.

Stop Seconds (Hacking device):

Though I started this post with the 3/4 plate, I actually started the project with the hacking mechanism. It is a simple one-part affair, that, rather than braking the balance wheel against the outer rim, brakes on the edge of the roller table. It operates in a linear fashion in a slot milled into the mainplate and is retained by the barrel bridge and the escape lever bridge. The tab engages the annular slot in the clutch gear, while the thin leaf at the opposite end applies the slightest friction to the roller table.

Balance Wheel:

The balance wheel is made using the lathe, the pantograph and hand work. The oversized blank is initially turned and center drilled in the lathe, then the blank is mounted to the shop-made positioning table, which is itself mounted to the pantograph table. The spokes are cut on the pantograph, using the plexiglass pattern. The pattern is cut, then the positioning table is rotated 90 degrees (15 clicks) and the pattern is cut again. The inside corners of the pattern are still pretty rough looking but this is of no consequence, since the stylus used (.312" diameter with .0312" cutter) never reaches the corners. After machining the spokes, the balance wheel is dissolved from its holding fixture and cemented into the lathe chuck, so that the height of the wheel's center can be machined to size. The final outside diameter is also established at this time. The balance wheel is then again set up on the positioning table so that the pockets for the Gyromax-style weights can be machined. These pockets are made using a shop-made cutter.

Making the weights...

Staking the balance staff...

Poising (more details on the poising tool can be found in the tools post)...

We'll revisit the balance wheel in a bit.

Jump Hours Mechanism:

The jump hours complication is one of my favorites, but it's usually paired with a "digital" type display for the hours. Since the dial is in regulator format, where the hours are read first, I saw no reason that it could not be paired with a conventional hour hand. So, that's what I did. All pivots in the mechanism are jeweled in order to minimize friction. The photos document the mechanism, in its originally designed format and, after minor alterations, its final configuration.

Making the star wheels...

The cocks for the star wheel train and the jump lever...

Making the jumper springs and lever...

The roughed-out jump train assembled. The configuration of the hour wheel lever would change in the final design.

Pressing the pivot into the new hour wheel lever...

I did not like the idea of having to continuously wind the minutes in order to set the hour, so I designed a "quick set" mechanism for the hours. It requires only that the crown be rotated back and forth, at the hour jump, to set the hour.

Here are a couple of videos. The more astute observer will note that I also jeweled the barrel arbor pivot.

Dial:

Let's move on to the dial (what there is of it at least)...

The photos are self-explanatory.

Hands:

The hands are made in two parts: the hand itself and a separate hub.

Finishes:

As with all else, all finishing, including plating, was done here, at my bench.

Mainspring barrel and cover "guilloche"...

Perlage...

Cotes de Geneve...

Anglage...

Skeletonizing the new setting wheel...

Plating...

Revisiting the balance wheel...

I was not happy with the first balance wheel, its style being incongruous with the rest of the movement. I was also not pleased with the balance weights being secured only by the friction on their posts, which I corrected in the new design. The new balance wheel is made of stainless steel but it was made in the same basic manner as the first. I made a pantograph pattern for one quadrant of the wheel and rotated the workpiece 90 degrees after machining each quadrant. This allowed for greater accuracy in the finished part than using a full pattern (pantographs do not make perfect circles). All subsequent operations were done before turning the outer diameter on the lathe (the excess material made it very convenient to handle). Aside from the styling and material, the main improvement over the first iteration is the method of securing the eccentric balance weights. Rather than simply being a friction-fit on a small-diameter post, they are a friction fit inside of a pocket, allowing for much more contact area between the weight and the wheel.

The spokes and weight pockets, roughed out...

Truing the inside diameter of the weight pockets...

The weight pockets trued and the spokes are finished. The material left at the bottom of each pocket allows for poising the bare wheel.

Centered in the lathe for turning of the outer diameter...

Drilling the bore for the balance staff. Final diameter is reamed to size.

Ready for installation of the staff and initial poising of the bare wheel (this is done in the same manner as the first iteration, so I saw no need to photograph the process again).

Making the balance weights. The material is turned and then eccentrically drilled in the lathe, then slotted (axially) in the milling machine. The collet block is then set up vertically and the weights are sliced off, each at precisely the same thickness.

The poised bare wheel and the plated weights, ready for assembly, then timing adjustment/dynamic poising.

Hairspring:

The "blank" hairspring came from my stock of same. They're pre-colleted with the correct downward offset for use with an overcoil, saving me at least that operation. After vibrating it to length, the overcoil "knee" is formed using shop-made tweezers and a surfaced basswood block. This method is surprisingly simple and precise, as long as care is exercised. The terminal curves are also formed using shop-made tweezers specifically for that operation. Finally, the hairspring is studded and the wedging pin is cut to length. I made the wedge pin much longer than needed so as to make it easier to handle during the studding procedure.

Vibrated length...