This is a remix of Niko’s Egg-painter robot (OpenBuilds) that will work with either 2040 or 2080 OpenBuilds V-Slot linear rail. Longer legs allows Niko's original control board mounting brackets that were designed to be mounted underneath to be re positioned in front to have the board mounted in front. An extension cord for the servo motor is needed to reach the control board when it is mounted in front. The pause and reset buttons on the control board are now available and this makes the unit much easier to use.
I used (2) 175MM lengths of Openbuild's 2040 Open V-Slot Linear Rail that was left over from a prior project. Also used a genuine eggbot Precision Egg Coupler, Precision Tail Coupler and EBB Driver Board, a Micro Servo 9g FS90 servo motor and homeade extension cord and (2) Nema 17 motors. Also used (11) M5x10mm Openbuilds low profile screws and tee nuts for the base assembly, and (6) additional M5x8mm screws were used for the optional Openbuilds v-Slot end covers if you wish to cover the ends of the 2040 or 2080 extrusions.
Precision Egg Coupler http://shop.evilmadscientist.com/productsmenu/51-accessories/208-coupler
Precision Tail Coupler http://shop.evilmadscientist.com/productsmenu/753
EBB Driver Board http://shop.evilmadscientist.com/partsmenu/188-ebb
.25" round stock, .25" washer, and the spring used for the Precision Tail Coupler were picked up at my local hardware store.
The legs used are Middleman's Reach3D 2040 Short Support Bracket Feet here:
http://www.thingiverse.com/thing:1967717. You will need to print off two pairs of these if you are using the 2080 Open V-Slot Linear Rail extrusion. I superimposed the standard part with a mirrored part in my slicer to share the center rail to create a one piece two leg part shown on the photos. Two of these one piece 3-rail feet hold the two 2040 extrusions together.
The OpenBuilds Nema 23 and Nema 17 motor mounts, V-Slot end caps and spacer block stl files that were used are OpenBuilds Parts by tjb1:
I 3D printed the Nema 23 motor mount bracket (Motor_Mount_Plate_NEMA23.stl) and spacer block (Spacer_Block_V_Slot.stl) and they are strong enough to perform without needing further modification. The 3D printed Nema 17 motor plate, (Motor_Mount_Plate.stl) however, was not strong enough by itself to work acceptably. The Nema 17 Motor_Mount_Plate.stl file was superimposed in slicing software with the nikosEB_4.stl file to create the modified egg motor mount used. The printed part is plenty strong enough but the motor mount center hole will need to be cleaned out after printing to allow the motor to mount.
The Precision Tail Coupler is designed to fit on a .25" shaft. While the Eggbot Pro and Niko's Egg painter both use a ball bearing to hold the tail coupler shaft, the other Eggbot models use plastic bushings and so does this model. The plastic bushing assemblies were printed by superimposing in slicing software the shaft_collar.stl file onto the nikosEB_4.stl file.
The pen arm used is the Distal pen arm for EggBot by tml here:
http://www.thingiverse.com/thing:696294. (fine.stl, pen_arm.stl, stepper_arm.stl, ultrafine.stl). The stepper_arm.stl file was mirrored to put the servo motor on the right hand side to work with the EBB Driver Board.
Two Thumb Screw Caps by artexmg (SetScrew1.stl), and (2) M4x25mm screws and nuts were used on the pen arm:
An additional M4 Thumbscrew by whisperoftheshot (m4_thumbscrew.stl), http://www.thingiverse.com/thing:25292 was used on one Thumb Screw Cap to hold the Distal Pen Arm assembly to the pen arm shaft coupler.
The pen arm shaft coupler is from nglasson's Improved printable eggbot here: