If your catches keep braking maybe it's time to replace them with something more durable.
I can't remember who posted the link to brass ball catches
, it may have been SacsTC (I apologise if it was someone else - I tried to locate the link to get this information correct but I couldn't find it).
Once my catches starts breaking, this is what i will be doing. They may cost a little more, but I am certain that they won't break in my lifetime.