I have many fun projects preventing me from getting anything accomplished. One is that I Mentor a high school robotics team in FIRST ROBOTICS each January through April, and enter my own Underwater ROV in an Underwater Robotics Challenge each June. And now I am trying to build a repstrap, so that I can build a Mendel, so I can work on a Gada Challenge Reprap design I call "Open Air" because it will be built as an enclosed cube, but with two sides missing so that over sized parts can stick out while the rest of them is being printed. Oh, and I also want to teach the High school teams to make their own printed circuit boards, design motors controllers and motor drivers using microcontrollers, and try to put together a middle school targeted robot starter kit with many expansions and room for novel designs by the kids.
I am currently part way through building a McWire. I have the water pipe frame pieced together and welded in place so the pieces wont keep slipping. I have most of the plastic plated cut and drilled, but have not put them together. I have two sets of stepper motors, two sets of stepper drivers, the Sparkfun ones and the Polulu ones, and also Mycom's reprap on a board circuit board that runs four steppers, two heaters, and 6 end stops from one ATMega/Adruino Mega. No I have to solder all the parts to the boards, assemble the McWire and switch it from 1/4 20 screw drive to taught cable drive, make an extruder, program the whole thing and get it running.
Instead I am experimenting with making extruder nozzles out of glass. The first practice pieces look promising. I want to see if I can add the nichrome heater wire and the thermocouple junction to the glass and the wrap the whole hot section in glass to hold the heat in. The glass is such a poor thermal conductor that not PTFE or PEET insulator will be needed at the other end, just clamp the glass tube in place with a rubber coated pipe clamp.
I am trying to keep my work posted and somewhat up-to-date on my own webpage, www.teamopenair.net/wordpress, and also on the team open air page in the reprap wiki.
Mike
