It's Alive!

So I finally decided to bite the bullet and test the machine.  I have been having a lot of problems getting the extruder to communicate properly with the host software for setting the extruder speed.  I think it has something to do with the slightly different motor drivers that I am using.  I have looked though the firmware and I can't seem to find anything that would be causing this, yet I can't for the life of me get the speed to be changeable via the software.  So instead, I hooked up a digital output from the Arduino to a 555 timer circuit that was constantly emitting a square wave with a time period I could vary via a 10k potentiometer.  This way I could change the extruder speed, but it would have to be done manually.  Works for the short term, but I will definitely keep working on this functionality for the future because varying the speed for different parts of the layer is vital.  For example to get an accurate outline of the layer you usually want to print those lines much slower than say the infill that doesn't need to be accurate.  Once I had the 555 circuit working and set to an acceptable speed, for the very first print, as is tradition, I tried to print the minimug stl.  This failed horribly.  So bad, I'm not even going to show you the pictures.  I had a ton of settings that needed to be tweaked.  I spent the whole afternoon tweaking these settings trying to get a decent print.  I also changed over to a square box stl that I made because I got the feeling my machine wasn't ready to print circles yet  :(   Here are some photos!

First few layers of the first "successful" print on the machine!

The resulting testbox that I printed

The major areas that I need to improve on right now are the filament thickness.  It is wayyy to thick right now.  It should be closer to 0.5mm not 1mm.  I think this has something to do with the speed I am extruding and moving the head at.  I think that if I move the head fast enough you could actually even stretch the filament out slightly to get smaller distances.  Similar to pulling hot glue out of a hot glue gun.  The strands get thinner and thinner as you pull on them.  It might have something to do with the heater temperature as well.  I'll have to investigate.  For reference all these prints were done at 240˚C and I had no problems with the first layers sticking to the plexiglass table that I am using.  I actually destroyed one print getting it off, so I don't think warping is going to be a problem with the ABS at this point.  I'll keep trying to tweak settings over the next few days and post back if I make some progress!