Case Openers: Overview

Opening watch cases is not the easiest of the watchmaking tasks. But it is always the first to be done. I admit that I was always very scared when opening watches, especially watches that were not mine. I do not like opening marks and scratches and assume that other people despise them too.
I have seen the most unbelievable examples of abused watch backs when browsing the flea markets in Bangkok. Yes, I know, tools are expensive, but trying to open a water resistant case back with slots with an old rusty screwdriver and chiseling parts off that case back is really barbaric. But it is obviously done quite often.

I soon realized that opening watch cases is a lot easier, if

• you have some practice

• you have the right tools

• you have holders or pads to put the watch on while opening them

I might have to add here, that you could buy one of those big case openers with a handle (they often work as case presses too), they cost around USD 500 to 700 and they come with a large array of bits to fit about any watchcase. If your budget and space allows that, then just buy one of those and you do not need to read further.

You are still reading? Great, then let us have a look at the various openers that come at affordable prices and let us see what we will be able to open with them.

Last but not least: It is a myth...
That a case back has to be closed with a huge momentum in order to guarantee water resistance. Many people use too much force when closing case backs. A gasket ring in good condition is much more important then too many KN (Kilo Newton) closing momentum!

A) Hand held case back openers

Types of Case Backs	Bergeon 5394 Movement Pad	JAXA Universal Case Opener Swiss Made (If you are more experienced, go for the single handle version)	The very "Poor Man's" Alternative: China Made Openers	Meikosha 19400 Made in Japan	Bergeon 5338-1 F Swiss Made**	Bergeon 5537 Swiss Made
Typical Asian street price (ca. 2003, since then we had an oil price almost doubled, so expect higher prices today)	USD 10	USD 100	USD 11 - 14	USD 50	USD 70	USD 80
For >>>	N/A	Cases with Slots Cases with round Holes	Cases with Slots Polygonal Cases*	Cases with Slots Polygonal Cases*	Cases with Slots* Polygonal Cases	Cases with Grooves (Rolex)

* grey choices in the  For >>>  row mean, that the case opener can open those cases, but is not the ideal tool.
** additional bits for the Bergeon 5338 are available: for Cases with Holes, Curved Edges and Cases with Grooves, although I would always prefer the Bergeon 5537 for Cases with Grooves

B) The professional Bergeon 5700Z and accessories

Bergeon 5700Z and Accessories	Explaining the Vice	Lug jaws	How to use it	Using Rolex openers 5537	5537 Mounted
Works with almost all case backs depending on the accessories and bits. You should see this Bergeon opener or a very similar opener in every professional watch repair shop. Once you have one yourself, you could not imagine how you opened watches before. The machine costs ca. USD 350 but reduces the risk of the watches being scratched while opened a lot.

C) Pocket case opener tools for case backs with slots (screwed case backs) and snap-on case backs:

D) Case opener tool for non-screw (snap-on) case backs:

Opening grooves
Please note that many watch cases or case backs provide opening grooves to facilitate positioning the opening tool. Sometimes the cut-outs in either the case backs or the watch case are very small and you probably find them with a loupe only or by driving your finger nail carefully around the edge of the case back. Common positions for grooves are

• Most often at the 5 o'clock position opposite the lower right lug (you are looking at the watch from the front with 12 o'clock pointing up)

• Alternatively the opening grooves are located opposite the other lugs at 7 o'clock, 11 o'clock or 1 o'clock

• Sometimes the grooves are right in between the lugs either at 12 o'clock or at 6 o'clock

• On some Seikos I have found grooves in the case back opposite the crown at 9 o'clock (e.g. the Seiko Quartz Discovery series).

It is really worth to look for these opening grooves as they allow a much saver positioning of the manual opening tool. The Case Crab opener below is especially helpful for very tight case backs or where an opening groove is missing. Please find additional Opening Hints here.