Recover the lost tip. If it has any broken pieces of the blade attached to it, those need to be removed before reattaching.

To remove broken bits of the blade, hold the tip tightly in locking pliers or bolt cutters (bolt cutter pictured on the left).

Pry off the broken pieces with another set of pliers.

If any small pieces remain, cut or break them off with a knife (be very careful).

Clean up the rim and stem of the tip as much as possible.