Seagull ST3600 (ETA 6497)

 A very good movement to start with.

Large ... started off as a pocket watch.

Size: 36.60mm diameter, 4.50mm height 

Power reserve: 40+ hours .

(Wind Friday morning and the watch runs until Sunday evening).

Accuracy: -20 to +40 seconds per day 

Beat rate: 21,600 vibrations per hour 

Full wind: 35 half-turns of the crown

Hand-wound --- simpler with fewer parts.

The ST3600 includes 17 jewels at critical friction points.

mainsprings store energy, 

gear trains transmit power

escapements regulate release.

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Disassembling a Seagull ST3600 (a pocket-watch movement similar to the ETA 6497) requires patience, steady hands, and an organized parts tray.

1. Preparation and Power Let-Down

Remove hands and dial: Pull off the hands with a hand remover tool, then remove the dial. [1]
Let down the power: Flip the movement over, trigger the click mechanism, and slowly let down the mainspring power until the balance wheel stops. [1]
Remove the balance complete: Unscrew and carefully lift out the balance complete first. It is very delicate and protects the hairspring. [1]

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2. Removing the Winding and Escapement Parts

Ratchet wheel: Unscrew and remove the ratchet wheel.
Crown wheel (Reverse Thread): Unscrew the crown wheel using a right-to-loosen (clockwise) and left-to-tighten rule, which is the opposite of normal screws.
Click and click spring: Remove the click and pick up the tiny spring underneath it.
Pallet fork bridge & pallet fork: Unscrew the thin pallet fork bridge and gently extract the tiny pallet fork with tweezers. [1, 2]

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3. Disassembling the Bridges and Gear Train

Barrel bridge: Unscrew and lift off the barrel bridge.
Train wheel & escape wheel bridges: Remove the main train wheel bridge and the small escape wheel bridge.
Gear train wheels: Take out the wheels in order: center wheel, fourth wheel, third wheel, and escape wheel.
Mainspring barrel: Lift out the main barrel housing the mainspring. [1, 2]

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4. Keyless Works and Motion Works (Dial Side)

Flip the movement: Turn the movement over to access the dial/plate side.
Setting lever spring: Remove the flat screw and the spring-loaded setting lever spring.
Yoke and yoke spring: Stabilize the high-tension yoke spring with a screwdriver, lift it out, and remove the yoke.
Motion works: Take out the minute wheel and intermediate wheels.
Stem and clutch: Flip back over, loosen or remove the setting lever screw that passes through the side of the movement, and pull out the crown, stem, sliding clutch, and setting lever. [1, 2]

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Lubrication

To oil a Seagull ST3600 (a clone of the ETA/Unitas 6497-2), follow standard mechanical pocket-watch lubrication practices, matching the exact oils and greases to the movement's load and speed. [1, 2, 3]

Discussions on the Watch Repair Talk Forum note that standard Swiss ETA 6497 technical and oil charts apply directly to the ST36xx series. [1]

Recommended Lubricants

Light Oil (e.g., Moebus 9010 or equivalent): Use on fast-moving, low-torque parts like the escapement jewels, escape wheel pivots, and fourth wheel pivots. [1, 2]
Medium-to-Heavy Oil (e.g., Moebus 90, HP-1300, or D5): Use on the center wheel, third wheel, and dial-side jewels. [1, 2]
Grease (e.g., Moebus 9504 or HP-300): Use on high-friction sliding parts like the keyless works, sliding clutch wheel, winding stem, and mainspring barrel walls/arbor. [1, 2]

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Step-by-Step Oiling Guide

1. The Mainspring Barrel

Barrel Walls & Coils: Apply a very thin film of grease (such as HP-300 or Moebus 9504) around the interior wall of the barrel and lightly coat the mainspring coils to prevent stiction.
Barrel Arbor: Lubricate the arbor pivot and points of high friction with heavy oil (HP-1300) or grease (9504). [1, 2, 3, 4]

2. Gear Train (Train of Wheels)

Center Wheel & Third Wheel: Place a tiny micro-droplet of medium/heavy oil (HP-1300 or D5) on the upper and lower pivots after the bridge is set. [1, 2, 3]
Fourth Wheel: Apply lighter oil (such as Moebus 9010) to the fourth wheel pivots as it rotates faster. [1, 2]
Rule: Never over-oil. A tiny droplet that covers about one-third to one-half the diameter of the oil sink is enough. Too much oil will bleed and stop the movement. [1]

3. Escapement

Escape Wheel Pivots: Apply a micro-drop of light oil (Moebus 9010).
Pallet Stones: Lightly grease or oil the tips of the pallet stones using a specialized grease like Moebus 9415 (or a tiny touch of light oil), letting capillary action form a microscopic film with the escape wheel teeth. Do not flood the pallet jewels. [1, 2, 3]

4. Balance Wheel

Balance Pivots & Cap Jewels: Oil the upper and lower balance jewel/cap jewel assembly with a very small drop of light oil (Moebus 9010). Use an automatic oiler if available to keep the drop uniform. [1, 2]

5. Keyless Works (Dial Side)

Winding Stem & Sliding Parts: Apply a thick grease (Moebus 9504) to the sliding clutch wheel, setting lever, yoke, and any sliding/friction points on the winding stem.
Setting Lever Screw: Place a microscopic amount of 9504 grease into the setting lever screw hole before seating the screw

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