>>1619287dude no... what the fuck
you can easily damage your headtube like this.
the tool is so easy to make. Just find a piece of pipe the right size, and cut some slots in it with a hacksaw. Pop it in backwards so the slots kind of ping into place around the cup. Then you can hammer on it with even force on all sides.
It's a piece of fucking pipe. THIS is the ghetto solution. What you're doing is just the full retard solution.