Heuer Monaco Case

Hi, This is my first post here and already have a question. Sorry for that.

40 years ago I bought my first watch and a day later, I opened the case back of the watch. My father caught me doing it. So that has been the story of my life since. I am not shy to check inside the watches and a while ago I paid my watchmaker to give me some private sessions on repairing Chronomatic movements.

I just got my first NOS Heuer Monaco Case, which had the usual molten gasket disorder. So the case was glued together like a tank. Now I don't remember how many watches I have bought in my life but a NEW MONACO was like a dream for me. But the molten gasket made it a little hard begin. I filled the case with acetone from the crown-stem-hole and the rubber began to puff out of the case and damaged the NOS crystal. I could have broken the crystal and clean the mess with acetone but trying to save the NOS crystal didn't work.

Now I have a question on the case construction. I have never seen anything like this. Two pieces pushed on each other and there are 4 hooks. Two of them are on the top around 10 and 2 and two on bottom around 4 and 8. I see Monaco owners disassemble the watches and take photos of the pieces but what is the trick in pulling the top and bottom part of the case without scratching or damaging the case? Luckily there was no movement and dial in my case, so I used force but even my watchmaker friend was wondering how?

I appreciate any help.

I remember a collector making their own Tool 033 from Lego (!), but unfortunately those photos have disappeared.

Below is some text from http://www.heuermonaco.co.uk that explains the right method:

"The back case of all original Monacos have this engraved upon them to indicate to the watchmaker the tool required to open the case. Because only authorised service centres tended to have them, these tools remain even rarer today than the watches themselves and are somewhat iconic within the Heuer community. Due to this scarcity and the unusual manner of opening, many Monacos have been opened by force over the intervening years, often resulting in cosmetic damage to the case. To open; the watch was rested upon the tool (as seen below). downward pressure was then applied to the plexiglass (via thumbs), the case then "popped" open. Thankfully it is normally possible to open and close the case by hand once the correct method is applied!"

Thanks for your help.

My case back has a sticker but I always wondered what that tool 033 means?

Just found some close up photos of the tool and I can't see anything that could push the hooks. It looks like a simple rest spot for the case to sit tight and the pressure from the top with thumbs on crystal forces the lower part to drop down.

I am going to look into lego or cast something but I am very skeptical on opening the case with only pressure on plexiglass. It breaks so easy and I need serious force to open it right now without the plexiglass.

See my other post on your quest for the crystal as I describe how you can seperate the case etc with your hands relatively easily.

Do not worry about the plexi at all it’s incredibly strong and you keep your thumbs out as wide as possible and you’ll be extra safe. But as you will see with the official tool you had to also push down on the plexi. Plexi is super strong and handles pressure very well. What it doesn’t handle well is shocks, so hitting it or dropping it is where the risk lays.

The Tool No 033 refers to that tool that is shown in Abrod520’s post above. If you look at the picture on the end of the block the watch is laying on you will see (upside down) Tool No. 033....that is the tool.

The tool does not push on the hooks that you refer to it is simply force that pushes it past them. Nothing else.

Thanks for the explanation, Gambba. I actually found out that the hooks have some sort of springs behind them and through the pressure on the crystal, which is transferred to the case back, the hooks loosen and the case back pops out.

Like I said in the other thread, I will try it when the new Crystal arrives.

I am just wondering if anyone has thought about using something else than the gasket. Gasket bleeding on vintage watches has been the source of so much headache but we are still using them. I am wondering if there is an alternative to that or a better material? Perhaps Kauchuk or a better rubber material?