I’ve drilled blank plates for phono sockets. The first one I’d engraved before drilling, it broke. 2nd attempt, drill before wasting my time with the engraving, it worked that time.
With several plates to make up I knew some would break so I bought two packs, before I’d finished I had to go to the wholesalers again. One had drilled perfectly, it broke as I clamped it in the engraving machine.
If the plates hadn’t been for me I’d have chucked the sponge in after the first failure.