The movement being ready to be disassembled. There is slight rusting on the balance bridge, and on the mainspring barrel arbor.
Dial side of movement, showing surface rust on the keyless gear.
This is the central rocking-lever wheel, showing the cap and gear, and two holding screws.
Hour and minute wheels. The hour wheel made of brass has no tarnish, the minute wheel has surface rust.
The rocking lever and mainspring (top) gear, and time-setting hears (bottom).
The mainspring click spring and talon shaped click.
View of the gilding underneath the keyless works.
The mainspring ratchet shows evidence of somebody cleaning the rust with simple sandpaper (non uniform finish, and sides bevels are not crisp...).
Mainspring ratchet taken off.
Balance bridge, and hairspring regulating index. This latter shows surface rust.
Another detail of the balance bridge.
Balance bridge removed.
Balance wheel. The hairspring retaining stud will need to be removed and refinished. The top of the hairspring collet is in excellent condition.
Bottom of balance wheel. Visible is the standard single-roller jewel table. Very good condition. The Balance wheel will have to be slightly resurfaced.
View of the escapement bridge. Note to the left, where the balance bridge was, there is some discoloration that will be removed.
Every bridge is hand-stamped with the movement serial number so that during its manufacture the watch could be successfully rebuilt.
Serial number ending in '96'. Since each piece was hand finished to the watch, the pieces are not interchangeable, as in modern swiss watches.
The rocking-lever cap is placed on a lathe to begin cleaning.
For this stage, a diamond powder paste is used to clean all surfaces.
Common cork is used polish. Since cork 'gives' it does not distort the surface architecture.
Rust is still visible, and it will be removed once the straight-graining is restored (done at a later stage).
Polishing in the same manner the screw head. These are 'flat' screw heads, in distinction to the normal 'bombe' styled.
Polished screw head. The flat surface is a trait of later late 19th- to early 20th century English watches.
The screws had a circular grain finish. Giving them a very 'industrial' aesthetic finish. They were not 'mirror polished'.
Finishing another screw, before.
After. The circular graining will be given at a next step of the restoration.
Cleaned screw with gear ready to be cleaned.
At this stage I use a rough-zinc block with diamond paste to take the surface rust off.
The original finish on these gears was straight grained, so this will have to be restored.
Initial view.
Further cleaning of the mainspring winding gear.
First step is finished, further work is needed.
The rocking-lever gear placed in a crown chuck.
This gear has sunburst finishing, so this will have to be refinished through a different method.
Cleaning of the time setting gear. The paste becomes darker with progressive work on the gear.
It turns near black when al the rust is gone.
Nearly finished. Ready for the next step in restoration.
Cleaning the mainspring click talon in the same way.
The click-spring cleaned.
The rocking-lever has slight rust too.
This was cleaned with the diamond paste.
The minute gear has a sunburst finish, and slight surface rust.
This gear will not be refinished further, as it would entail removing the pinion, which can damage it beyond repair.
Here the cannon pinion is to be extracted. As often happens, it is rusted into place and cannot be removed.
In order not to damage the movement finishing, a staking tool has to be modified to punch out the center wheel pinion.
The punch has to be reduced to a diameter of .45mm. Since the punch is in hardened steel, it is turned on the large lathe.
Turning of point to .45mm diameter.
Placing the punch in the staking tool (soft wood with a hole to accept the center wheel pinion is used as a support).
Giving a soft punch to the center wheel pinion.
The center pinion has displaced by .75mm (see space below the pinion). Ready to be extracted easily.
Now the crown wheel is extracted with the hand removing tool.
Cannon pinion removed, and center wheel pinion is seen.
As noted before extraction, the pinion was slightly bent. This is rectified before removing.
Back of movement, with center pinion protruding.
View of pinion from back of movement. English watches have a two-piece center wheel (with the separate pinion, seen here, that carries the cannon pinion).
Cannon pinion is purposefully 'rough' as it has to be carried by the center wheel, and also have enough grip to carry the cannon pinion.
Main plate after the removal of all clicks, gears, and pinions.
Removal of the gear train bridge. Swiss movements do not have this extra bridge.
English watches have this bridge as it allows for easy servicing of broken jewels.
Removing escapement bridge on movement back. Here the escape wheel, and the pallet lever are seen.
Bottom view of escapement bridge, with last two digits of serial number stamped.
English screws have a different terminal shape than Swiss. The 3/4 bridge plate screws finish in a pointed end as seen here. The other, longer, screws are case-holding screws.
The 3/4 bridge removed, the gears have been sealed to the bridge by dried oil.
Underside of main plate, showing three pillars, and openings for the gears.
Gear train: Mainspring (1st), center wheel (2nd), third wheel, and fourth wheel, which traditionally carries the small second's pinion.
Reverse of mainspring. Seen here is the 'Geneva' safety stop. So that the mainspring cannot be overwound, and thus potentially broken.
Center wheel, with visible grime present.
The hollow center wheel. A distinguishing feature of English watches. Swiss watches have a solid center wheel with a protruding pivot carrying the cannon pinion.
Third wheel pivots are in order and will need to be polished.
Fourth wheel pivots are also good, no rust.
Checking jewelling on the main-plate. All jewels are in good order.
Jewels in the 3/4 plate are also in very good condition.
Jewel bushings (or chatons in French) are in good condition.
The traditional brass mainspring arbor bushing on English watches. Here has some surface rust.
Bottom of the bushing. Since English watches use a short but very strong steel mainspring, they tended to warp the thin brass 3/4 plate.
The use of an easily removable brass bushing allows for a quick servicing if the mainspring turns out of truth.
Placing the bushing in a collet to remove the rust.
Before polishing.
After initial polishing.
Visible here is an indentation on the bushing. This is a place marker so that the bushing can be inserted in its precise position on the movement.
The position mark on the 3/4 plate shows where the two marks have to align. The use of these position markers is a typical quality of English watchmaking.
The gilded surfaces are cleaned without solvents nor abrasives, as the vintage gilding can be very delicate. A cotton swab is used to gently clean the gilding.
Their effectiveness is very good on these surfaces. Ultrasonic baths can actually damage the gilding. This depends on how the gilding has aged.
Surface has undergone a first cleaning. The watch will be cleaned again before final timing tests are carried out.
The dial side of the main-plate needs lots of cleaning.
Click spring, located on the movement side of the mainplate, under the 3/4 plate. To push the rocking bar in the mainspring locking position.
Work on the steel components of the balance bridge begins.
As this profile image shows, the gold pin (top most) that usually keeps the hairspring in place, is used decoratively here.
The pin is removed, showing the surface rust on the hairspring index.
The gold pin extracted.
The hairspring index arm is pressure fitted, and kept in place by a 'snap-on' lip. Swiss watches use the balance pivot jewel cap as a way to retain the index in place.
The special shape to allow the hairspring index to snap on, this is distinctly English in design.
The underside of the hairspring index arm.
Using diamond paste to start polishing the arm.
A household piece of cork is used to remove the rust of the curved area.
Placed on a block to remove more surface dust.
Here the notch at the end of the index becomes visible. A simple but subtle detail.
Next is the box shaped hairspring stud for the flat hairspring.
It is crucial to reposition the stud back at the exact place so that the watch beats correctly.
The underside of the balance, showing position of the retaining stud.
Further image showing the placement of the stud, with the splinter almost removed.
The brass splinter is pushed out, thus releasing the stud and hairspring.
The hairspring stud, it presents the most surface rust of the whole watch.
The face of the stud with the hole for the hairspring. The change in color is rust, not a reflection.
Taking off the first and thickest layer of rust with diamond paste.
The more one works the piece into the paste, the color and consistency begins to change in relation to the increased flatness of the surface.
Initial rust removed.
However, the piece is full of micro abrasions that will need to be removed on a zinc block.
Hairspring index arm with rust removed, with same issue as the hairspring stud.
The notch has cleaned up well. Further polishing is in order so that the geometry of the cut is not altered.
Checking if the gear-train runs true.
Rechecking the rust on the pivots.
The pinion leaves are in good order.
However, the top of the pinions have some slight surface rust that will be removed at a later stage.
The finishing on the center wheel pivot is not as thorough as on Swiss work.
This is because the center wheel doesn't create sufficient friction to merit a jewel (which is usually for decorative purposes).
Using regular cork to clean the pivots (before a thorough cleaning).
Placing the gears in the main plate.
Placing the mainspring to check initial clearance.
Side view of movement without mainspring (not fully pressed)
Detail of pillar that supports the 3/4 plate
Gear is free and engages perfectly.
Typical of English watches is a liberal end shake on the gears (the gears have space to move up and down on their pivots).
Checking the truth of the mainspring barrel.
The mainspring arbor bushing is replaced to check barrel truth.
Seems out of truth by simple inspection.
See how the teeth engage with the center wheel, the barrel runs out of truth.
At the other point of the barrel it engages as it should. This is a typical problem that will be sorted in the coming weeks.
The ratchet wheel click is worked on first.
This is a vintage, 1920s brass polishing block. It has two 'legs' and the third is formed by the piece being polished.
The front of the piece separates to be able to insert screws, or the pins of steel parts. Here the click is attached with schellack.
This is a zinc plate and the polishing block.
Before every use the zinc plate needs to be re-surfaced. With a high 1200 grit sandpaper one marks a cross-hatched pattern to help provide resistance to the polishing compound.
It is essential that the piece rest perfectly flat on the plate, it is checked from all angles.
Here is a side view.
Starting out with a coarse diamond paste.
Some paste is taken by the part and slowly worked in a circular manner.
After quite a few tries with different gradients of diamond paste, some decent results start to appear.
It should be perfectly flat, without scratches, and have a deep reflection.
This finishing is already better than the original (which had faint straight-grained lines), but still can be better.
The sides are dirty, and are cleaned with oilstone paste.
The sides are straight-grained finished.
The zinc block is cleaned and resurfaced, as I had carried out various tests for the click.
Oilstone powder is used now as a first cleaner, since the gears show a bit heavier rust.
This powder is mixed with some oil. Depending on how much oil one adds it has an impact on the 'bite' of the powder on the piece.
I've added a lot of oil for the action to be smooth and thus take longer to remove surface material.
This oilstone paste creates a matte, or a finish similar to 'sand blasted'. Many Swiss watches have this finish.
Since the gear has a central opening, I don't need to attach it to the polishing block.
After the first few minutes of polishing the luster starts becoming visible.
This is halfway into polishing (you can see some paste still on the surface).
The procedure was repeated with two other gears, here are the four pieces polished.
The spring for the click is set up on the polishing block and it will be polished next.
Here I'm continuing to polish the spring click. The whole ensemble was left covered so no dust would come into the polishing pastes.
The spring click polished.
Working on the center portion of the mainspring ratchet wheel, here you can see that it has been hand sanded at some prior dates, all angles are 'curved' and not straight.
Polishing on the zinc plate.
The central portion is perfectly flat and has attained a black polish. The sides and bevel will need to be done on the lathe at a later point.
Using a brass bar to create a pinion leaf polisher. Usually this is done with wood, but here I am using brass to remove some of the surface dust.
Starting to part the brass rod.
Parting continued.
Brass bar parted.
Turning the portion that will be used as a polisher.
Starting to turn the ridge that will clean the interior of the teeth.
Initial form.
Testing, still not the right geometry of ridge to fully engage teeth.
Proper shape achieved. The final, actual shape is done by the piece itself, the iron of the gear is considerably harder than the brass, and forces the tooth shape to emerge from the brass.
Cutting the central hole to be fitted on the watchmaker's lathe.
Parted and ready to be mounted.
Mounted on the arbor. Normally this operation is done with a separate tool that mounts it perfectly perpendicular. However, I am running the lathe with a hand pulley and gently rotating it so that it cleans only the slightest surface rust.
While not shown here, the gear is charged with a diamond paste, and each tooth subject to 3-4 rotations of the brass wheel. This photo shows how it's done.
Initial polishing of teeth. I cannot over polish (or remove all traces of slight rust) so as not to change the shape of the teeth, which damages their long term functionality.
Turning a similar piece, this time out of raw walnut wood. I am here using a lathe at a family barn about 2 hours south of Rome.
Outer bark removed.
The walnut (pear wood is traditionally used in Switzerland, i.e., a hardwood is required for this) is half or quarter sawn to make this piece.
I cut the piece into a rough square, through drilled and placed on a straight axis and then turned to a round on the lathe.
The round part is now held in the chuck, and the bevel for the teeth shaped. Here through boring of hole for the watchmaker's lathe arbor.
Parting off.
Here the same operation is carried out, previous to charging the gear with polishing paste.
The gear above is not cleaned, the below gear was only cleaned the brass wheel.
Small gear after wood disk.
Smaller polished gear on bottom (after brass and wood disc), in comparison to above which still needs to pass through the wood disk.
Looking at the mainspring barrel.
Taking off the geneva stop arbor. The single tooth on the arbor that's removed limits the total amount of times the mainspring can be wound. This prevents breakage, and keeps the watch in the best power ranges for the type of mainspring used.
Inside of the top main spring barrel (this portion faces the dial).
The mainspring arbor and barrel.
Mainspring disassembled. The mainspring of typical short and strong English quality.
The bottom seat of the barrel, note how it is slightly deformed, conical and has some imperfections. This is caused by the force of the spring, and hence over time cause a 'wobbling' of the barrel around the arbor.
The seat is shaved clean (less than a 1/10th of a millimeter is removed, which is well within tolerances for this part).
Cleaned arbor seat.
The same procedure is carried out to the barrel cap.
The arbor itself has dried oil, mixed with iron dust which if uncleaned compounds the problem.
Arbors are polished, previous to polishing.
After polishing.
Cleaning upper arbor (the hole on this portion is what keeps the mainspring ratchet wheel from sliding off on the dial side, a splinter runs through this hole).
Pinions cleaned.
Checking the truth of the barrel. This is done without the spring. The barrel seats will likely have to be slightly 'closed' in order to grip the arbor more tightly.
The barrel turns true, and will then be checked with the mainspring in place and see how it affects truth.
Here I'm setting up the pivot polishing tool on the watchmaker's lathe for the center wheel pivots.
The center wheel placed in the polishing bed, it will not be driven by the pulley as it would be too much friction.
A pivot polisher, it has a fine cross-grain so that it can be charged with diamond paste.
Here I'm just gently polishing the pivots with my hand (the center wheel is turned by hand, and not carried by the pulley).
The Jacot Tool is the traditional tool to polish pivots, this example is from the 1920s.
Here I will be only briefly polishing the pivots, literally about 2-3 turns with the pivot polisher charged with diamond paste.
Here I show how the 'faceplate' is driven by a gut string on a small arch (Due to making the photo the string is not positioned correctly). This operation was carried out for the center, 4th and 3rd wheel.
The pinion ends show some slight rust which will be removed.
The back of the pinion is held in the chuck, and polished with the pivot polisher charged with diamond paste.
This is after, like the pivots themselves, the top of the leaves are cleaned very quickly in just a few seconds.
The top of the 3rd wheel pinion leaves cleaned similarly.
And lastly the escape wheel pinion leaves.
Having touched up the mainspring barrel arbor hubs last week, now I check truth with the mainspring installed.
The mainspring is wound and inserted in the barrel so that it is not distorted (which creates uneven timekeeping rates).
Barrel closed, this is the side that face the movement back (this end is visible through the brass bushing).
The brass bushing is screwed back on (the screws need refinishing as they are scratched).
The barre is hand wound and released and it keeps true.
The barrel tried again and keeps true. The next step, once the whole watch is finished with the restoration, is to try again before installing the balance wheel, and then with the balance wheel.
In order to refinish the mainspring ratchet wheel, and the rocking lever center wheel a series of polishing discs need to be made.
This is a small brass disk, here it's been given a hole to accept the polishing arbor.
Parting.
Parted. I've left one side with a slight taper to meet the ratchet wheel bevel.
Next turning a larger steel disc.
Initial boring hole.
Starting the parting off area.
Previous to finishing the parting I drill the hole for the arbor.
Parted off.
Creating a slightly rougher finish on the other side.
Rougher finish.
Finer finish.
Next and last is a zinc disk. Here I am refinishing the face.
A fine finish to carry the polishing diamond paste.
A large brass disc with a finer finish for polishing.
Only the outer band will come in contact with the steel parts to polish.
This is a tin full of natural shellac. It is a tin from the 1970s that I purchased years ago with a lot of tools from the Liverpool area.
This is the head of a chuck designed to hold pieces with shellac. Two flakes are placed and the brass is heated until the shellac melts.
The the part is pushed into the shellac and left to cool.
Shellac from a previous use.
That shellac was removed, and new flakes placed, this is the rocking lever center wheel.
On the watchmaker's lathe, the brass chuck is heated with a flame to soften the shellac and the piece is then turned and centered with a toothpick.
This is the setup of the item on the chuck, with the counter wheel with the steel disc. The discs are to turn in contrary directions to create the snailling.
The rocking lever cap needs circular graining which is done with a graduation of sandpaper from 400-1000-1200 grit. Here it is dirty with my fingerprint.
Placed in the watchmaker's lathe.
The finished product.
I have mounted the ratchet wheel on the lathe to center it, as it is currently cemented off center.
This is how it is centered, as the piece revolves it is centered by pushing the opening to one side, which forces it to self-center.
The brass portion is heated to make the shellac become soft again.
The ratchet wheel centered, and I have straightened the side large bevel on the wheel.
I polished the teeth, and the outer, larger, portion is ready for snailing.
Here I'm using a spare ratchet wheel which I will use for arriving at the correct snailing. A piece of shellac is shown next to the ratchet wheel.
The brass portion is heated with an alcohol flame.
The ratchet wheel is cemented.
Before fully cooling off, I reheated the brass and centered the wheel. I will return to this at a later point.
I will refinish the two outer escapement bridge screws as they are rusted.
The two screws need to be cleaned of surface rust. The bottom of the screws can be seen on the movement side, and have received polished ends.
Placed on the chuck.
And polished with diamond paste. The other screw had slightly more surface rust so it was first sanded and then polished.
The first screw, what is noticeable is that the screw-head slot is slightly off center, evidencing that it was hand cut.
Both screws polished. They were cleaned and rinsed in acetone to clean all traces of oil, as this effects the bluing process.
Placed on a bed of fine brass shavings. Here I use an old silver watch dial as a heating tray.
The screws are placed over the alcohol flame so that I can control the temperature and thus the correct hue of blue.
Not distinguishable here, but the screws are a deep blue-purple hue.
Placed back into the movement. They will be removed many times still so it is possible I will repeat this process to clean any scratches they may receive.
Here I am starting to disassemble the watch after the previous session.
the 3/4 plate is taken off and the mainspring barrel Geneva stop work addressed.
The Geneva stop work prevents the mainspring from being overwound, and also keeps the mainspring tension in best torque range for timekeeping.
Here you can see some of the surface rust settled on the mainspring barrel.
Zinc plate is prepared.
The screw set in the polishing block.
Adjusting the block.
Halfway through polishing.
Screw head polished.
The Geneva stop wheel, it has surface rust as well.
After a good amount of time it came out new.
The mainspring barrel arbor, had a rather deep rust spot, it took a considerable time to move through different coarse grits up to the proper polishing grit.
The arbor placed against the 3/4 plate once it was finished polishing.
Now onto the ratchet wheel restoration. Here I am modifying the milling attachment. The grey 'L' shaped steel has been made to facilitate the proper angle on the spindle.
A pin is being manufactured to create the pivot where the spindle will rotate and create the correct angle.
The pin for the spindle mount.
Now a new drawbar for the spindle is being made. The original spindle drawbar had a small amount of concentricity that was suitable for cutting certain parts, but not for this operation.
The end was threaded, the original drawbar is placed for comparison.
The whole drawbar has to be turned between centers so that it is sufficiently concentric.
The turning is done in stages so to minimize flex of the drawbar, and hence, maintain concentricity of the spindle draw-bar.
The spindle is inserted to the drawbar to check fit, and it is a correct fit.
The hub for the polishing wheels is turned, and the piece is parted off.
Now the front of the drawbar thread is created. Since the front thread only functions to fasten the piece, it does not need to be concentric.
Rough thread with visible taper.
This is turned off to reduce the length.
Drawbar back-end will also be reduced.
Portion reduced.
Original (top) and and new drawbar for comparison on the bottom.
Testing the drawbar and positioning on the milling attachment cross slide.
This week I concentrated on cleaning up and refinishing the screw heads. They all have a polished circular grain finished.
The screws are placed in the lathe.
The screw heads are dressed with a piece of fine grain sandpaper placed on a flat surface.
The two rocking lever center cap screws are mirror polished (bombe shaped).
After polishing with successive diamond micron papers. They needed substantial attention as the screw slots were quite marred.
A good our and half of work on this plate.
Next I refinished the minute pinion that moves from the back of the movement out to the dial side.
Not clearly visible here, but the button end has some dents. Not all of which were removed.
Placed on the lathe, and worked in the same manner as the screw heads.
Here you see that a portion of the screw head has a dent (this only became apparent after I polished the end).
A treatment on the zinc block solves this problem. i moved from a rough 400 grit up to 1/4 micron.
Nearing the mirror polished effect.
Arrived at the desired result.
The final piece for this week's work was the click spring that is not visible, but requires attention as any surface rust can compromise not only the part but the other gears and pivots.
Starting to arrive at a mirror polish.
Mirror polished achieved. The sides and back will have to be treated now.
A series of pulleys was attached to drive the second spindle in counter-clockwise direction to create the snailling decoration.
A test on an old hour wheel giving very broad arches, the diameter of the snailling wheel needs to be reduced.
Here giving the snailling wheel a step to create more pronounced lines.
Further testing on a spare ratchet wheel.
I started fine polishing the hairspring index.
This piece has proven quite difficult to polish. I have spent a good 1.5 hours on it so far without results. So I left it and returned to it.
Here I am polishing the hairspring stud.
Further work on it remains once I free up the polishing block.
Continued working on the hairspring index.
Mid way through polishing.
Arriving at a dent polish.
But there are still fine scratches. So the polishing process goes back a few steps.
In the meantime I decided, after examining the wheel under better magnification, to try cleaning with diamond past.
The result was very good and the original stailling came out very well. This is good news.
Here a better view of the snailling.
Another attempt at getting the index to polish up well.
However, it is not happening. A probable reason is that the metal is not properly tempered.
So I will continue next week with another attempt, if not I will arrive to a suitable polish that will be good, will have small intrusions.
The dial side jewel screws had a black sheen to them that normally means they are slightly rusted, however, with some careful cleaning they showed their deep blue hue.
With some solvent and a cotton swab, the screws cleaned up very well. They will be further cleaned before testing the watch.
While the jewel screws on the back side of the movement seemed OK, they also showed good results when cleaned.
Staring to mount the watch again in order to catch items that need particular attention.
Here I'm cleaning the geneva safety stop key. It had surface rust on some of it's faces.
This cleaned up very well.
The minute wheel, made of brass, cleaned up nice also.
The mainspring ratchet click need it's sides cleaned.
Here is a detail of the surface rust on it that was removed.
The click springs (Mainspring and rocking lever) needed their lateral surfaces cleaned also.
These have a brushed finish.
The movement dial side being temporarily assembled. The two large ratchet wheels are missing.
After having failed to get a decent finish, I repositioned the index regulator, and tried again.
This time I was able to achieve an acceptable result.
It is polished but not to the level that it could be. It's very bright and acceptable, but not perfect.
The snailing attachment for the lathe is set up, and ready to snail the ratchet wheels.
The intermediary rocking lever ratchet is snailled successfully.
The mainspring ratchet wheel before snailling.
After snailling.
Another angle to show the reflections.
Both wheels next to each other.
Assembling the watch.
Placing the gear train together.
Movement assembled.
Dial side assembled.
The movement is dissassembled again in order to do some final touches.
The balance wheel has some slight rust on it as well, and this will be removed on the lathe.
The balance screws are removed, and their position recorded. It will all receive a cleaning before assembly.
The bottom of the balance is cleaned first.
Then the top, more visible part.
The balance reassembled. The rust wasn't taken off all entirely as this would have meant changing the overall weight of the balance. But the rust should be stable now.
Dissassembling the escapement jewels for cleaning.
The original mainspring prooved to be too fatigued.
A new mainspring is fascioned from a slightly larger one.
The mainspring was cemented on a chuck, then with a grinder it's thickness reduced to size.
The new mainspring on the left, with the portion removed so that it is the same lenght. A hole at it's outer extremity was drilled so that it can attach to the mainspring barrel pin.
Testing the movement.
Instaling a holding pin on the movement mainplate in the place of the original. Here a steel screw, instead of a brass pin is used.
This helps stabalize the clockwise shake of the movement when it is being wound, it is a facet present even when cased in the original pocket watch casing of the 19th century.
I decided to make a new center pinion, as the original one was slightly bent, effecting the watch when the time was set.
Being turned to size, each portio has a slight taper to it, so that it pressure fits into the center wheel hole.
Checking size and fit with the center wheel and minute wheel placed on the center pinion.
Mirror polishing the end of the pion as the original.
Placed on the movement.
Timing the watch in differnet positions, and comparing this to performance on the wrist.
Bluing the balance wheel bridge screw before the final assembly.
