I received this Helvetia watch in a batch from the united kingdom.
It didn’t run too badly, however, it did have an amplitude on the lower end and it was nearly one minute slow. Also, the movement itself was filthy. A few very little hairs and dust particles.
Finally, it seemed like it’s been previously over oiled. Little puddles of oil were on the base plate and underneath the barrel bridge.
The movement is the in-house Helvetia 64. A hand winder with 17 jewels. It’s a 13’5 ligne movement so it’s rather big for a vintage watch.
I’d date this Helvetia watch to the 1950s.
As always, remove the power from the mainspring first. This way, the escapement can’t be damaged when working on the gear train. Move the click away from the ratchet wheel while letting the crown slip between the thumb and index finger.
After the power is released, take away the balance and the pallets. The pallet cock was terribly greasy and the bearing jewel had some particles on it. When I removed the pallets, the train wheel moved a little bit. There must have been some residual power stored in the gear train but the grease and dirt provided enough resistance to cancel it. Imagine what that does to the amplitude and thus the rate of your watch.
Flip the movement to remove the cannon pinion. Without the cannon pinion removed, the center wheel can’t be lifted.
Remove the ratchet wheel and the crown wheel with its shim. After that, you’ll be able to lift the barrel bridge. It’s obvious that this movement has been over oiled in the past.
Remove the train wheel bridge (as you can see, the escape wheel bearing jewel has a Kif Duofix capstone setting). Then, lift the wheels and at last the main barrel.
Flip the movement to the dial side and begin with the set lever spring. After that, take away the minute wheel, yoke with its spring, the setting wheel, and the set lever. The hour wheel and the cannon pinion have been lifted before, as you remember.
Clean all the parts in the watch cleaning machine.
After the cleaning process, start with the main barrel, wheel train, and the wheel-train bridge. It’s very important to reinstall the wheel-train bridge very carefully. Gently hold some pressure on the bridge with a peg wood while guiding the wheels into their correct positions. You can guide the pinions with brass tweezers or an old oiler. You can also try to ping the movement holder with your fingernail and hope that these vibrations cause the wheels to fall into place.
Install the barrel bridge, ratchet wheel, and the crown wheel. Don’t forget to slightly lubricate the inner ring of the transmission wheel before you fit the transmission wheel boss. As you may notice, the barrel bridge is a bit tarnished and appears to have a different color than the rest of the movement. This could be the result of an aggressive cleaning solution that has been used before. Or it could be that this part had to be replaced in the past and this part came from a “donor movement”. I don’t think this is the case here because the balance cock is also slightly damaged. The damage is on the side that connects with the barrel bridge.
Flip the movement to start work on the dial side. Fit the crown wheel, castle wheel, the yoke and its spring. Then, replace the set lever, setting wheel and the minute wheel. The keyless works are covered with the cover plate with the check spring (combined known as the set lever spring).
Flip the movement again to fit the pallets and the pallet cock. Before I fit the pallets, I like to lubricate the exit stone with Moebius 9415. After the pallets are installed, reinstall the balance.
Remove the Incabloc (jewel holes and endstones) to clean and lubricate. I always use One Dip to clean shock protection parts.
Lubricate the capstones with a tiny drop of Moebius 9010 in the middle.
Do you have a Helvetia watch too? What do you think of them? Let me know in the comments below.