Here are my experiences from assembling the mk3 kit. First off I am fairly handy when it comes to kits electronics etc. I still made mistakes. It is imperative to follow the directions exactly. Even though I thought I did I still messed up.It took me 3 days to complete the kit. I worked several hours a day and quit when I was tired of it. The entirety of the process was enjoyable. I was not missing any parts nor were any broken or unusable.My first mistake was putting the extruded aluminum pieces on the wrong places. They were on the correct side of the frame but switched. Fortunately I caught it fairly early and remedied the situation. As an aside I would highly recommend using t handle hex wrenches. They make the process much more enjoyable.During the assembly process of the filament feeder bearing there is a step that requires press fitting a pin. I had to ream the hole with a drill bit in order to get it to fit. I recommend this also as the piece looks fairly weak and forcing it with a hammer etc would probably break it.My biggest mistake was putting the bed frame onto the y axis rods backwards. I had the two bearings to the right of the machine instead of the left. This made attaching the heated bed in the correct orientation impossible. I was pretty far along when I caught this. Lots of lost time here.I was concerned with the electronics assembly especially the cable management when I first read the directions. The process is actually well thought out and was much easier than I anticipated. Just take your time and follow the guide. All of those wires will go in the box and look good if you have patience. I had no trouble at all with the connections.After completing the kit the real frustration began. I could not get the self test to finish. It would fail stating that the x axis was the wrong length. I repeatedly tested the motion by hand checked the belts and pulleys and lubed the rods to no avail. Off to Google we go. It took a lot of searching but I finally found a post where a guy stated that he overtightened the back plate on the extruder assembly and that caused a similar problem. I loosened all of the screws on this assembly and the problem went away.My next and largest frustration was trying to calibrate the xyz. It would always home the Z axis then go down to the plate and stop with an error to check the axis. Again I checked lubed tightened etc. and could not solve the issue. I found no instances of the forums of my exact problem. I spent hours on this problem and was tempted to tear it all down and start over. Finally my son and I were able to find the problem and boy did I feel stupid. I had attached the spool holder on the wrong side of the frame. In doing so the z axis could not go all the way to the top to home itself. Once fixed it worked.I am done calibrating testing etc and the first print is underway. I really enjoyed assembling this kit and would not hesitate doing another. I hope that others can learn from my mistakes and have a smooth path to 3d printing. http://ift.tt/2BOIMAy