I am creating an industrial version of the 3D printing pens that you see on the market. In fact it really wouldn't compare to the pens but more to a MIG welder but of plastic. I will create a hand held unit that will have the hot end in it and possibly the extruder. I would like it to act like a welder where when you pull the trigger it will extrude and two other settings; 1. for the heat and 2. for the extrusion speed. What is the application? I am a sculptor and create enlargements of my work with a 3D printer. I then need to reassemble the many pieces and the best way to do that is to use the same base material that was used for the print. I currently use 3DoodIers pens but burn through them as the work load is hours a day. What do I need? I need direction from members here as per the electronics (and maybe coding?) The part that is easy for me is the physical build and design. What parts do I need and what is the best way to go about this? In return for the help I will post the progress in detail in the event that someone else will want to build one of these as well. I currently have some electronics OSOYOO 3D Printer Kit: RAMPS 1.4 Controller + Mega 2560 board + 5pcs A4988 Stepper Motor Driver with Heatsink + LCD 12864 Graphic Smart Display Controller with Adapter For Arduino RepRap I'm thinking the E3D V6 with either the direct drive titan or set it up as a bowden to save on weight. I can custom make the gun. What else do I need?