with a hammer. any hard surface will work, but there can be marks on it after so use nothing to fancy. the hammer is just an ordinary builders hammer nothing fancy at all. we hammer the thread to make it harder, as it first was to soft to be able to use as pins.
i try to hammer the thread all around, it will become a bit flat but we will sand it later so no worries.
sand it down with a piece of fine sand paper.
then cut the pin in two, try to cut at an angle. this will save you time later.
when just cut the end are a bit to 