The "Calamari Kid".

Never trust a Caped Calamari...

The "Calamari Kid" is the third in a series of "illusion" themed automata I've designed. With a press of the calamari kid coin ("CK"), the model performs a "shell game" themed illusion.

Inspired by the "swedish handcraft" hand cranked shell game themed automaton, this model is a battery powered motor driven electro mechanical design utilizing gears, cams, levers, arms and wheels to create a similar shell game illusion in a "pre-calamari" (octopus) form factor. Drawing an average of 9ma of current (maximum 14ma, minimum 7), the mechanism is easily suitable for solar powered operation.

As usual I probably forgot a file or two or who knows what else, so if you have any questions, please do not hesitate to ask as I do make plenty of mistakes.

Designed using Autodesk Fusion 360, sliced using Cura 4.6.1, and 3D printed in PLA on an Ultimaker 2+ Extended, an Ultimaker 3 Extended and an Ultimaker S5.

Thick cyanoacrylate glue.

Wire (28AWG stranded).

Double sided tape.

I acquired the following parts for this mechanism:

• One N20 6VDC 30RPM gear motor (on line).
• Two 6mm (diameter) by 1.5mm (thickness) neodymium magnets (local hobby shop).
• Three 3mm (diameter) by 1.5mm (thickness) neodymium magnets (local hobby shop).
• 6VDC AAA battery holder (on line).
• Four AAA batteries (my battery stash).
• Six M2.5 by 16mm screws (local hobby shop).
• Six M2.5 nuts (local hobby shop).
• Three micro roller lever switches (CYT1096).
• Three 8mm (5/16") ball bearings.

The attached file "Parts.pdf" contains the name, quantity, layer height and infill of all 3D printed parts I printed for this mechanism. Note that "Barrel.3mf", "Button.3mf", "Octopus, Head.3mf" and "Stein.3mf" are dual extrusion parts.

This mechanism is a high precision print and assembly using at times very small precision 3D printed parts in confined spaces with highly precise alignment. I printed the gears, levers, arms, cams and wheels using the Ultimaker Cura 4.6.1 "Engineering Profile" on my Ultimaker S5, which provides a highly accurate tolerance requiring minimal if any trimming, filing, drilling or sanding. However, prior to assembly, I still test fitted and trimmed, filed, drilled, sanded, etc. all parts as necessary for smooth movement of moving surfaces, and tight fit for non moving surfaces. Depending on your slicer, printer, printer settings and the colors you chose, more or less trimming, filing, drilling and/or sanding may be required to successfully recreate this model. I carefully filed all edges that contacted the build plate to make absolutely certain that all build plate "ooze" is removed and that all edges are smooth using small jewelers files and plenty of patience to perform this step.

This mechanism also uses threaded assembly, so I used a tap and die set (6mm by 1, 8mm by 1.25) if required for thread cleaning.

To assemble the table, I performed the following steps:

• Attached one roller lever switch to ""Bracket, Switch.stl" using two M2.5 by 16mm screws and two M2.5 nuts.
• Slid "Button.3mf" into the button hole in "Table.stl".
• Attached the switch bracket assembly to the table assembly using "Bolt (8mm by 30mm).stl".
• Adjusted the switch such that the button was full up when released, and activated the roller lever switch when pressed.
• Soldered two 10mm lengths of white wire to the roller lever switch, one to the COMMON (C) pin and the remaining to the NORMALLY OPEN (NO) pin.
• Pressed two 6mm magnets into the hole in "Holder, Magnet.stl".
• Slid the magnet holder assembly into the slot in the table assembly.

To assemble the base, I performed the following steps:

• Positioned "Gear, Compound (1m 28t, 1.867m 28t).stl" between the drive towers oriented as shown, then secured the gear in place using "Drive.stl" and "Axle, Drive.stl" such that the pin on drive was oriented as shown when fully tightened (If the pin is not in the position shown, remove the axle, rotate it 60 degrees, then repeat until it does.).
• Secured "Pin, Axle, Gear, Compound (1m 56t, 1.867m 17)" into the threaded hole in "Axle, Gear, Compound (1m 56t, 1.867m 17).stl".
• Positioned "Gear, Compound (1m 56t, 1.867m 17t).stl" onto the base in the position and orientation as shown then secured in place with "Axle, Gear, Compound (1m 56t, 1.867m 17).stl" and "Nut, 20mm.stl".
• Secured "Pin, Axle, Gear (1m 14t).stl" into the threaded hole in "Axle, Gear (1m 14t).stl".
• Positioned "Gear (1m 14t).stl" onto the base in the position and orientation as shown the secured in place with "Axle, Gear (1m 14t).stl" and "Nut, 20mm.stl".
• Secured "Driven.stl" onto the base assembly using "Axle, Driven.stl" making sure the driven wheel aligns with the drive wheel.
• Positioned the short pin on "Arm.stl" into the slot in driven, slid the arm around the slot such that the threaded hole aligned with the axle hole in the base assembly, then secured the arm onto the base assembly using "Axle, Arm.stl".
• Attached one roller lever switch to the tower closest to driven wheel using two M2.5 by 16mm screws and M2.5 nuts.
• Rotated the compound gear ("Gear, Compound (1m 28t, 1.867m 28t).stl") clockwise as viewed from the front of the assembly and adjusted the driven wheel microswitch to "click" when encountering the stop pins on the driven wheel.
• Attached the remaining lever switch to the tower closest to drive wheel using two M2.5 by 16mm screws and M2.5 nuts.
• Rotated the compound gear ("Gear, Compound (1m 28t, 1.867m 28t).stl") clockwise as viewed from the front of the assembly and adjusted the drive wheel microswitch to "click" when encountering the stop slot on the drive wheel.
• Pressed "Gear, Motor.stl" onto the gear motor shaft.
• Pressed the motor assembly into the "Base.stl" motor mount holes just far enough to allow access to the motor terminals.
• Soldered a blue wire between the driven wheel microswitch COMMON (C) pin to the drive wheel microswitch COMMON (C) pin.
• Soldered a blue wire between the driven wheel microswitch NORMALLY CLOSED (NC) pin to the drive wheel microswitch NORMALLY OPEN (NO) pin.
• Soldered the red wire from the battery holder to the motor "-" terminal (required for the motor to turn counter clockwise as viewed from the motor shaft end of the motor).
• Soldered a wire between the drive wheel microswitch NORMALLY OPEN (NO) terminal to the motor "+" terminal (required for the motor to turn counter clockwise as viewed from the motor shaft end of the motor).
• Soldered the black wire from the battery holder to the drive wheel microswitch COMMON (C) terminal.
• Soldered the white wire from the table microswitch COMMON (C) terminal to the drive wheel microswitch COMMON (C) terminal.
• Soldered the white wire from the table microswitch NORMALLY OPEN (NO) terminal to the drive wheel microswitch NORMALLY OPEN (NO) terminal.
• Pressed the motor further into the motor mount engaging the motor gear with the compound gear ("Gear, Compound (1m 28t, 1.867m 28t).stl").
• Positioned the top over the base, placed the long pin on "Arm.stl" into the slot in "Yoke.stl", then secured the top assembly to the base assembly using four "Bolt (M6 by 4mm).stl".

To assemble the bracket, I performed the following steps:

• Slid "Yoke.stl" into "Bracket.stl".
• Positioned "Gear (1m 56t).stl" into the bracket assembly as shown and secured in place with "Axle, Gear (1m 56t) making certain that both the yoke and gear are centered.
• Attached "Mount, Octopus.stl" to the bracket assembly using "Nut, 17mm.stl".
• Attached the tentacle assembly to the bracket assembly using two "Axle, Mount, Tentacles.stl".
• Attached the two "Octopus, Head, Eye.stl" to "Octopus, Head.3mf" using thick cyanoacrylate glue.
• Attached "Cape.stl" to the octopus head assembly using double sided tape.
• Attached the octopus head assembly to the tentacle assembly using double sided tape.
• Slid "Arm, Lift.stl" into the assembly.
• Pressed one 3mm magnet into the top of each "Cup.stl" in identical polarity as the magnet holder.
• Glued the three cups into "Octopus, Tentacles.stl" using thick cyanoacrylate glue.

For final assembly, I performed the following steps:

• Attach the bracket assembly to the base assembly using two "Bolt (M8 by 12).stl" making sure the pins on the axles align with the slots in the yoke and lift arm.
• Attached "Growler.stl" and "Stein.3mf" to the table top using double sided tape.
• Positioned the three ball bearings in the cups.
• Attached the battery holder to the base using double sided tape.
• Slid the "Barrel.stl" into the base assembly and secured in place with four "Bolt (M6 by 4mm).stl".

And that is how I 3D printed and assembled the "Calamari Kid".

I hope you enjoyed it!