Watch Repair


  Barrel Complete

Wear INSIDE your watch!

A "Reverser"

What YOU should know BEFORE having your automatic, mechanical watch "repaired" or "serviced."

We have developed the following specific customer information after repairing numerous watches which have been improperly serviced.

You, the customer, must be better informed about what should be done to your modern, automatic, mechanical watch when it receives full service, or an "overhaul."

We appreciate that many of you who own an expensive watch are on a tight budget, and are inclined to price shop a repair for your high-end watch.  However, many watch repair shops are also hurting for business and/or have very little business (can't pay their bills), and/or are utilizing unethical techniques to repair your watch.  These inferior practices save the repair shop time and money, AND they will result in your watch running and perhaps even keeping time. 


First, let us explain a few simple facts about your modern, automatic, mechanical watch:

  • Your watch is designed to "wind" by you wearing the watch and your arm's motion causing a revolving weight in the watch to "spin."  This is why your watch is called an "automatic."  You can also "wind" your watch manually via the use of the crown (or the knob that you set the time with).
  • The revolutions generated by your motion cause a gear, called a "reverser" of "reversers" (plural) to operate and transfer the rotational energy through a series of gears to a mainspring which is housed inside a mainspring barrel. 
  • The reversing wheel(s) is unique in that it functions to allow the revolving weight to transfer its rotational energy to the gearing system regardless of which direction it happens to turn.  If this part is worn, improperly cleaned or improperly oiled, your "automatic" watch will NOT wind properly!
  • The mainspring in an automatic watch is also unique in that it is designed to "slip" when it reaches maximum wind.  This slippage is critical, and functions both to protect the watch from over-winding, and to generate the maximum and consistent torque necessary to power the watch.  Consistent power means the watch can more easily be precision tuned to keep better time, and the service interval can also be maximized.
  • Having just read the above, you now know more than 95% of the counter staff at any jewelry store where you purchased your watch and where you may be tempted to have it serviced.

When your modern automatic watch receives complete or full service, generally required about every 5-7 years, there are two (2) very critical parts that should be replaced, not repaired, but REPLACED*:

  1. The mainspring barrel complete, and
  2. The automatic reverser(s)

*Depending on the caliber of movement and its eccentricities, there may be other parts which should be replaced outright, but are beyond the scope of this information.

When you call to inquire about a watch repair, ask, "What specific parts are going to be replaced when you service my modern automatic watch?"

What ANSWER do they provide?

  • "We replace everything recommended by the manufacturer."  (Not good enough.) 
  • "We send your watch out to a "qualified" watchmaker and he or she knows what to replace." (Not good enough.)
  • "We always replace the mainspring."  (Close, but not good enough - you will learn why - keep reading.)
  • "We only replace what needs replacing."  (Sounds like this will save you some money.  NOT TRUE.)
  • "We send your watch to the manufacturer and they know what needs to be done."  (Better, as the manufacturer will ALWAYS replace these items, but how do you know they are truly sending your watch to the manufacturer?  Why don't you send it directly to the manufacture yourself?  Plus, the jewelry store is going to tack on a percent profit for the repair as is their right, but it would shock you to know how much this percentage is!)

On the left we have a mainspring barrel for an ETA 7750.  This caliber of movement is found in many high-end chronograph watches.  But this is no ordinary mainspring barrel.  This mainspring barrel comes preloaded with a factory-fresh mainspring, and arbor.  It has also been greased/lubricated at the factory and torque tested to insure it is 100% perfect.  On the right we have a reverser, and the front and back of the packaging from the factory.  The above parts are new, and expensive.

In this ETA technical drawing the large red arrow is pointing to the location of the 'reverser' within its exploded parts orientation in the watch movement.  The double-dot arrows are lubrication points, all of which must be hand-applied in the correct quantity, onto perfectly clean surfaces during re-assembly.

But WHY are these parts so critical to replace?  Can't they just be repaired (cleaned and re-lubricated)?

  • The mainspring lives inside its barrel where it winds and unwinds - CONSTANLTY. 

The mainspring barrel with its lid or cap removed.  This mainspring barrel came out of a 7750 we serviced.  It has approximately five years of wear pattern inside.  The red arrows are pointing to the scoring (small, raised "ridges") on the surface of the cap.  There is a similar amount of wear on the floor of the barrel, beneath the coiled spring.  Seeing is believing.  This wear can not be "cleaned" off. 

Lubrication might minimize the effects of these "ridges", but will NOT eliminate them.  As a fully-wound spring unwinds to power your watch, the spring will encounter the "ridges" and will "hang up" ever so slightly, affecting the smooth transmission of power/energy to the train of wheels it must drive to power your watch.  And this impacts the watch's ability to remain consistently accurate as the spring unwinds. 

In this ETA technical drawing you can see the mainspring barrel 'exploded' with its components: the barrel proper, the mainspring, the arbor and the barrel cap.  The double-dot arrows (above) are pointing to places where the barrel components must be properly lubricated IF the barrel is re-used and/or opened and cleaned for any reason. 

  • The Mainspring & Barrel Components 

The mainspring has been removed.  Again, note the red arrows pointing to wear patterns inside the barrel.  Look at the almost perfect coil pattern of the spring.  This spring is tempting to clean and reuse, because it is not seriously deformed.  But it is WORN.  The barrel is WORN.  It should NOT be re-used.  Time for new parts!
  • A new mainspring in its package - tempting to just install this inside a clean, USED & WORN barrel.  Why?  To save money, that's why.

This is the part many watchmakers are installing in your mainspring barrel, IF you even receive a new spring!  Nothing wrong with this, as long as you barrel is not WORN.  We see re-usable barrels in well-used modern automatic watches about .00000001% of the time.  What does that tell you, the customer? 

If you send us your watch to repair, you can rest easy knowing that we will service it properly, and return the parts in question to you should you specify this on your repair authorization.

And just in case you believe that all of this information is "HYPE," feel free to READ our owner's professionally published article on the subject:

If you are ready to ship your watch for a prepaid repair estimate, please click here.

BestFix Watch Company is a state-of-the-art watch-repair facility.  For inquiries, please use the Ask the Watchmaker Form.

BfW Co. Inc.


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