I´d like to know if …

Hi Dave, i´m from Brazil. I appreciated your projects, but my doubt is relacionated for security. People says me that the resistance used to warm up (to do the plastics get hot) may cause electric shock on people manipulating it. I´d like to know if there is some sense in this issue, because, first of all, security is essencial, isn´t ? Thank you.
Other issue, is it possible you send me or publicate photos showing inside the extrusor, injection machines, especialy the electrical parts?