Crystal press for the Omega 167.005

That OP press looks like it might twist the crystal as it tightens. Even if there is a slip-joint, there could be some angular stress.

I JUST did one using one of these(the press does NOT rotate!), but with nylon dies like the one in your top picture. I too snapped my first one, and did a deep dive bit of research that really helped me 'maximize' my chances.

FIRST most important thing was to make sure that the case where the crystal was going into was spotless. Any amount of rust could increase the friction/break it, any dirt/dust/etc could cause problems, make sure it is flawlessly clean. The same goes for the outside of the crystal.

Second: Make sure the case is supported all the way around, and that it is flat. I put a nylon die that fit perfectly 'inside' the outer ridge of my 168.005 case and used that to hold it. It damaged the die, but it held the case perfectly straight and centered. Pressing slightly 'offcenter' can cause problems as well.

Third: I LUBED up the side of the crystal. This one I saw some mixed reviews of, but I used my case gasket silicon 'greaser' and rolled the side of the crystal in it. I presumed this would reduce the press friction and make it really easy to go in.

Doing all of that, the crystal went in with significant, but not overly so, force. It went perfectly! Because of the 3rd step, I washed the case inside and out (ultrasonic cleaner, then water + air to dry).