Trying to service a movement but ran into a new one.

Anyone know how the crown wheel comes off a Ronda 1239-21? It looks more like a rivet than a screw. Thanks in advance

Just to follow up. Yes apparently the crown wheel on some of theses are riveted to the plate. What a crappy design.

Can you remove it with the bridge as one unit?

Just to close this topic off - yes, the bridge came off with the wheel attached. I just threw it in the ultrasound just as it was, and then tried to jam some oil down it, basically just over oiled it, let it sit overnight and then wiped all the excess off I could. Seemed to work reasonably well if not ideal.

Watch is now running - a successful adventure. Never do one of those again if I can help it.... lol