hanging out at a workbench on the work bench other side of the room.

Alright @quality if your still online I wanted to ask you this, I need some help. I finally got my movement serviced and running perfectly. But honestly? Putting it back in the case and making sure it's actually waterproof terrifies me more than the gear train. Where do I even start?

ahha your right next me, That’s completely normal! A lot of beginners treat the case like an afterthought, but it’s the armor protecting all your hard work. If the case fails, a single splash of water ruins the movement anyway. What’s giving you the most trouble right now?

Just getting the case open without scratching it! I have a screw-down caseback on this dive watch, and my three-pronged wrench keeps slipping. I’m terrified I’m going to gouge the steel.

Oh, the classic slip-and-scratch. First trick: ditch the metal wrench for a moment and grab a sticky friction ball. It’s just a grippy rubber ball filled with air. You press down hard and twist. It won't scratch anything, and it opens about 80% of screw-down backs.

And if it’s screwed down by a gorilla?

Then you use the wrench, but you must adjust the prongs so they fit the slots perfectly with zero wiggle. Put plastic wrap over the caseback first to act as a barrier, push down with 90% of your force, and twist with only 10%. It’s all about downward pressure so it can't slip. For snap-on casebacks, look for the tiny "lip" or notch. Use a proper case knife, leverage it against your thumb, and pop it away from your body so you don’t stab yourself if it slips.

Good tips. Now, what about the crystal? I need to press a new sapphire crystal into this case. I have a hand-lever crystal press, but I’m scared I’m going to crack the glass.

Crystal pressing is all about die selection. You need nylon dies that match the exact shape of your watch.

• For the bottom die (holding the case), it needs to support the bezel firmly without pressing on the case lugs.
• For the top die (pressing the crystal), it must be slightly smaller than the crystal if it’s flat, or hollowed out if it’s a domed crystal so you aren't pressing on the highest point of the dome.

Do I just smash it in?

Heavens no! Clean the case crystal seat perfectly. Check the I-gasket (the plastic ring the crystal sits in)—if it’s shaved or pinched, replace it. Then, press down gently until you feel it seat, rotate the case 180 degrees, and press again. This ensures it goes down perfectly flat. If it goes in crooked, it will crack or leak.

Speaking of leaking, let’s talk gaskets. I see people slathering silicone grease all over caseback O-rings. Is more better?

Absolute myth. Silicone grease does not seal the watch. The physical compression of the rubber gasket against the metal seals the watch. The grease is just a lubricant so the turning caseback doesn't pinch, stretch, or tear the rubber as you screw it down.

So how much do you actually use?

You want a microscopic film. The easiest way is to use a gasket greaser box—it’s a little round tin with two grease-soaked foam pads inside. You drop the gasket in, close the lid, twist it, and it comes out perfectly coated. If you see chunks of grease squeezing out of the caseback, you used way too much and it’s going to migrate into your movement. Also, don't forget the crown gasket! Everyone forgets the tiny o-ring inside the winding crown or on the stem tube.

Okay, it’s all put together. How do I actually know it’s water-resistant? Do I just drop it in a glass of water?