I broke the mineral glass of my Triwa watch. Sent them an email, they sent me a free new glass as long as I fixed it myself. So I did…
Bought a toolkit from DX to disasemble the watch, and removed the crown by pushing a needle in the marked hole (se picture). At the same time I changed the battery.
After I removed the movement/dial, I pushed the glass out from the inside of the case. The glass is originally pressured on from the front with a silicone sealing making it fit. I did not manage to push it out, so I simply broke it.
I placed the watch facing down on some hard surface with paper protecting the case, placed the head of a screw driver against the glass from inside the case and used a hammer gently on the screw driver to make the glass break. Then it was easy to remove the broken glass. Next I gently pushed the new glass on to the front. Then placed the watch facing down onto a hard surface and used some pressure to fit the glass.
Now it should be fine for at least a while.