The Rolex Microstella Tool
The Microstella is Rolex system to adjust the balance wheel to make sure the watch
keep the COSC standard. To do that there is a special tool to adjust the screws with.
The old tool looks like this and it's oil filled to be a little more exact and stable.
At the backside there is graduation which means 1 second per day for the low type of head nut and 2 seconds for the high type of head nut for each line.
A closer look to the tool.
Here we have a balance wheel with the Microstella screws.
Here is how it works.
A few pics of the tool in action.
The instuctions from Rolex.
And some pics of the new/current Microstella tool.
Photo credit for the new Microstella tool: Tony Axelzon
So lets put up a watch at the timing machine. Not good -17 seconds a day.
So I pull off the bracelet.
With the Ref 2100 tool.
Take place in the case opener.
Off we go.
Let the fun begin
This is a little tricky.
22 minutes later we are close. A little low amplitude so maybe a service will made it perfect in the future.