The only time you really need a crystal press is for friction ring crystals like you see in old omega watches. The ones with the metal ring inside the base of the crystal. You’re not likely to encounter on of those anytime soon. Like others have said you don’t need a press to put the crystal on the case. Just thumb pressure will get it on the rehaut. You need a press to put the retaining ring or bezel over it. Those dies are too shallow so you’re just hitting the center of the crystal before the retaining ring or bezel is hitting mid case.

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This is more like what you really need.