2729-ETA-09

Mainspring Winder for ETA-calibres

The 2729-ETA-09 mainspring winder coils the spring to size before transfer directly into the barrel.

$165.00

Prices are as the listing last showed them.

Reference	2729-ETA-09
Reference line	2729
Drawer	Hands & Movement Work
What it is	A tool in its own right
Bench job	Fitting hands

We make the 2729-ETA-09 for winding mainsprings on specific ETA calibres. The tool takes the bare spring, draws the coils tight around the central arbor, and holds the pack square so you can push it straight home into the cleaned barrel. It belongs on the movement assembly bench beside your tweezers and oils.

Arbor and drum fit

The winding arbor catches the inner hook of the mainspring while the drum contains the outer coils as you turn. Both parts are turned to match the internal diameter of the target ETA barrel.

Controlled spring transfer

A central plunger pushes the coiled spring out of the drum and into the barrel floor in one steady motion. This keeps the spring flat during insertion so the coils do not pop out of plane.

Grip on the handle

The knurled body gives your fingers purchase while winding against the resistance of the mainspring. You hold the outer sleeve with one hand and turn the winder crank smoothly with the other.

Bench storage

Store the 2729-ETA-09 dry in a partitioned tray or rack to keep the drum edge and arbor hook clean of lint and bench debris. Wipe the steel contact surfaces clean before each assembly.