So after 10 days of 24/7 3D printing 53 different parts on my Lulzbot Mini I have solvent welded together BB8s upper frame.

The frame is rock solid. Standing on the outer shell it supports my weight no problem. It its probably a lot stronger and heavier than it needs to be. It weighed in at 4.5 lbs. So the full weight of the frame will be 9lbs. Or about 1/4 the max thrust we will get from our motors.

I setup one door and one motor lifter to see how well they worked. The supplied drum that came with the winching servos for the lifter was to wide to lift the motor all the way so I printed a spindle with about half the diameter and now it gets up no problem. The door has a bit of trouble with it bending down under its weight so it gets caught and doesn't close properly. There are a few ways to remedy this. Right now I am using a rubber band to offset the sag, but I could also use a bearing on the outside of the slide to keep it more upright. The shafts for the slide and hinges are also undersized so more accurate shafts should reduce the slop. The last possibility is printing the doors hinge pieces so its natural state is to sit to high up. This way its sag set it into the right position.

Because of the sagging I had a problem with one of the servo motors. The servo motor that ran the door was stalling when it got caught closing and one of the driver FETs got damaged.

I intend to replace the servo boards with OpenServo boards. This way I can control them via I2C and get feedback on position and power usage to see if they have stalled. I will use the existing boards for the winching servos which are full size but I will have to design a board for the doors microservo to fit it in.

That's all for this post. I get more plastic this wednesday so I can start printing the lower frame. So stay tuned in for that.