Parts. I acquired the following parts: • One 6VDC 30RPM N20 gear motor. • One 4AA battery pack with switch. • Four AA batteries. • Five 8mm diameter ball bearings. • Ten 5mm diameter by 3mm thick neodymium magnets. • Three 3mm diameter by 1.5mm thick neodymium magnets. Unless noted otherwise, I 3D printed the following parts at 15mm layer height, 20% infill with no supports: • One "Arm, Fixed.stl". • One "Arm, Lift.stl". • One "Arm, Track End.stl". • Two "Axle, Arm.stl". • One "Base.stl". • Four "Bolt (M6 by 1 by 5MM).stl". • Seven "Gear, Paddle.stl". • One "Housing, Paddles, Fixed.stl". • One "Housing, Paddles, Lift.stl". • One "Mount, Housing, Paddles, Fixed.stl". • One "Paddle, Tabbed.stl". • Six "Paddle.stl". • One "Pin, Stop.stl". • One "Rack, Fixed.stl". • One "Rack, Lift.stl". • One "Rail, Lift.stl", 100% infill. • Seven "Retainer, Paddle.stl". • One "Track.stl". • One "Wheel, Yoke.3mf". This is a high precision 3D print and assembly model using at times very small precision 3D printed parts in very tight spaces. Prior to assembly, test fit and trim, file, sand, etc. all parts as necessary for smooth movement of moving surfaces, and tight fit for non moving surfaces. Depending on you printer, your printer settings and the colors you chose, more or less trimming, filing and/or sanding may be required. Carefully file all edges that contacted the build plate to make absolutely certain that all build plate "ooze" is removed and that all edges are smooth. I used small jewelers files and plenty of patience to perform this step. The model also uses threaded assembly thus an M6 by 1 tap and die will assist with thread cleaning if necessary. Lift Housing Assembly. To assemble the lift housing, I performed the following steps: • Pressed one "Gear, Paddle.stl" into one "Paddle.stl" aligning the slot in the gear with the paddle. • Slid "Rack, Lift.stl" into "Housing, Paddles, Lift.stl". • Positioned the paddle assembly in the housing assembly. • Secured the paddle assembly in the housing assembly with one ""Retainer, Paddle.stl". • Repeated the previous three steps for the remaining three lift housing paddles. • Pressed one 3mm magnet into the magnet pocket in "Arm, Lift.stl". • Pressed four 5mm magnets into the magnet pocket in the lift housing assembly such that the polarity attracted the lift arm. • Positioned the lift arm on the lift housing assembly and secured in place with one "Axle, Arm.stl" making certain the arm, rack and paddles operated with ease. Fixed Housing Assembly. To assemble the fixed housing, I performed the following steps: • Pressed one 3mm magnet into the magnet pocket in "Rack, Fixed.stl". • Pressed three 5mm magnets into "Housing, Paddles, Fixed.stl" such that the polarity attracted the fixed rack assembly. • Slid the rack assembly into the fixed housing and adjusted the magnets for smooth operation. • Pressed one "Gear, Paddle.stl" into "Paddle, Tabbed.stl" aligning the slot in the gear with the paddle. • Positioned the tabbed paddle assembly in the top most hole of the fixed housing assembly such that it angled upward 10 degrees, then secured the assembly in place using one "Retainer, Paddle.stl". • Pressed one "Gear, Paddle.stl" into one "Paddle.stl", positioned the assembly into the fixed housing, then secured in place with one "Retainer, Paddle.stl". • Repeated the previous step for the remaining gear, paddle and retainer. Attach The Lift Housing To The Base. To attach the lift housing to the base, I performed the following steps: • Pressed "Rail, Lift.stl" into "Base.stl" (glue may be required). • Installed four AA batteries in the battery pack. • Soldered the battery pack wires to the motor such that the motor shaft rotated clockwise when viewed from the motor shaft end of the motor. • Pressed the motor into the motor pocket in the base assembly. • Slid the lift housing onto the lift rail. • Pressed "Wheel, Yoke.3mf"onto the motor shaft while sliding the wheel pin into the lift housing yoke slot. Attach The Track End Arm To The Base. To add the track end arm to the base, I performed the following steps: • Pressed three 5mm magnets into the magnet pocket in the base assembly. • Pressed one 3mm magnet into the magnet pocket in "Arm, Track, End.stl" such that the polarity attracted the arm to the base magnets • Attached the arm assembly to the base assembly using one "Axle, Arm.stl" making certain the arm rotated with ease. Attach The Fixed Housing To The Base. To attach the fixed housing to the base, I performed the following steps: • Pressed "Mount, Housing, Paddles, Fixed.stl" into the base assembly (glue may be required). • Attached the fixed housing assembly to the upper end of the mount using two "Bolt (m6 by 1 by 5mm).stl". Final Assembly. For final assembly, I performed the following steps: • Attached "Pin, Stop.stl" to the base assembly using one "Bolt (M6 by 1 by 5MM).stl". • Attached "Arm, Fixed.stl" to the lift housing assembly using one "Bolt (M6 by 1 by 5MM).stl". • Pressed "Track.stl" into the base assembly. • Attached four rubber sticky pads to the bottom of the base assembly. With assembly complete, I performed final adjustments on the stop pin position, fixed arm angle and fixed housing assembly position such that the paddles passed a single ball bearing from the end of the track the the beginning. And that is how I 3D printed and assembled, "Marblevator, Paddle Lift". I hope you enjoyed it!