This is a peristaltic pump designed around 4/6 mm silicone tubing and driven by a JK42HS48-1204 stepper motor. I printed the parts in PLA for testing — works fine so far, but long-term durability hasn’t been checked yet.
BOM
The model does require some supports when printing. For assembly you’ll need:
8 × ball bearings 3×7×3 mm
2 × ball bearings 8×22×7 mm
1 × steel rod Ø5 mm, cut into 4 shafts ~12.5 mm each
4 × screws M2.6×6 (short)
4 × screws M2.6×12 (long)
Silicone tube 4×6 mm (tested with standard aquarium air hose)
Silicone tube connector (Prevents the tube from being pulled into the pump; it should be installed as close as possible to the housing on the suction side).
Assembly is straightforward once you have the hardware. The pump runs pretty smoothly and is easy to adapt for fluid transfer projects, though keep in mind this is still a prototype.
Assembly instruction
Rolls
Assemble all rolls, push two bearing on both sides of the roll.
Put a shaft rods into bearings
Rotor
Push roll shaft sockets into both bottom ant top rotor parts
Put rolls on shafts into a sockets
Finalise the rotor assembly by putting on in the right orientation the bottom part, screw it together tightly.
Main Pump Internals
Put a silicone tube into one hole on a casing, put a bottom bearing and the rotor into, mind the connector which should be as close as possible to the casing
By rotating the rotor put the tube in a place all around
Pull the tube through the second hole
Push the ring into it's place in the casing so it limits the tube vertical movement