Eight passive slots
V2 has exactly eight slots. They sit on a bar on top of the frame, with no motors, wiring or electronics. The printer's own extruder drives them.
MECHANICAL SYSTEM
How it works
One filament change on Mechams V2, step by step. The printer's own extruder drives all eight slots, so there are no electronics to add.
STEP 01 · GEAR TRAINEXTRUDER TORQUE · BELT DRIVE
The extruder drives a belt that turns the spur gear.
The extruder turns the lower of two pulleys on the toolhead, and a belt turns the upper one. That pulley drives the spur gear, the only part that ever touches a slot.
STEP 02 · SLOT BANKTOP BAR · 8 PASSIVE SLOTS
The slots have no motors.
Each slot sits on the top bar with a spur gear on its left, and only turns when the toolhead rises into it. The bar takes eight slots; this example uses two.
STEP 03 · PRINTPRINT HEIGHT · EXTRUDER ACTIVE
Printing starts in orange.
The toolhead is at print height, and the extruder pushes orange filament through the nozzle onto the gold PEI plate.
STEP 04 · CUTZ UP · X TO THE CUTTER PIN
To change colour, it first cuts the filament.
The toolhead lifts, then moves right until its lever hits a fixed pin at the end of the gantry. Pushing further drives the blade through the filament above the extruder.
STEP 05 · DOCK · SLOT 2Z TO MAX · GEARS MESH
Then it docks at the old slot.
The toolhead moves under slot 2, which holds the orange filament, and rises to max Z. There its spur gear meshes with the slot's spur gear from below.
STEP 06 · RETRACTEXTRUDER REVERSE · ROLLERS PULL
The orange filament goes back up its tube.
The extruder runs in reverse. Through the gears, the slot's rollers grip the filament and pull the cut end back up the PTFE tube into the slot.
STEP 07 · WIPENOZZLE WIPE · 3 PASSES
It drops out of the dock and wipes the nozzle.
The toolhead moves left to the wipe pad and makes three passes over the wiper.
STEP 08 · DOCK · SLOT 1SLOT 1 · Z TO MAX · GEARS MESH
Then it docks at the new slot.
Same move as before: the toolhead goes under slot 1, which holds the white filament, and rises to max Z until the gears mesh. Now the extruder drives this slot's rollers.
STEP 09 · FEEDEXTRUDER FORWARD · INTO THE HUB
The white filament feeds down to the nozzle.
The extruder runs forward. The slot's rollers push the white filament down its PTFE tube, through the toolhead hub and into the nozzle.
STEP 10 · PURGEPURGE BIN · NO TOWER ON BED
It wipes and purges over the chute.
At the rear of the bed, the nozzle is wiped and the leftover orange is purged over the chute into a bin; the A1 wipes first, the A1 mini purges first. There is no purge tower.
STEP 11 · PRINTPRINTING · STOCK FIRMWARE
Printing carries on in white.
The toolhead goes back to the print and lays the next layers in white, on top of the orange. It all runs on the stock firmware and the stock nozzle.
STEP 12 · PARKPRINT COMPLETE · STANDBY
When the print is done, the toolhead parks.
It moves back to the wipe pad and rises to standby height. You can start with two filaments and add more later, up to eight; every slot is the same passive part.
V2 HARDWARE
What V2 changed.
The short version, for anyone planning a build.
One PTFE tube per slot
Each slot has its own tube, straight into the toolhead hub. Nothing joins or splits a tube on the way. PTFE can't be printed, so you bring the eight tubes yourself.
One tolerance: 0.20 mm
That is the only tolerance that ships. The parts are made for a calibrated A1 or A1 mini with the stock nozzle.
No AMS Lite needed
With V2 fitted you don't need the AMS Lite, and no part of it is reused. Your printer stays on its stock firmware.
PLA body, TPU drive, standard bearings
Print the frame and body in PLA; no supports needed. The belt and the filament drive gears are TPU. Buy MR115ZZ bearings (11 mm outer, 5 mm inner, 4 mm wide): five for the toolhead and four for each docking station.
No runout sensor in V2
Keep an eye on your spools on long multi-colour prints and swap one before it runs dry.