Three types of conveyor ends have been used successfully:
- Motor end in ¾” MDF
- Pulley end in ¾ MDF
- Pulley end in ¼ MDF
These pulleys built from ¾” frames have turned out way better than I thought they would. I first used 1mm thick belting at 100RP; this was a bit under powered. All the power is used to move the thick belts. It would move a full gallon of milk with no issues.
With the 0.15mm thick belting that is currently be used the motors can be smaller, especially if you put in ball bearings.
Motor end in ¾” MDF Parts:
- 25MM Gear motor, 4mm shaft 100-1000RPM
- 2 motor mount screws: M3-0.5 6 mm screws
- 3D printed gearbox bracket
- 3D printed D-coupling to take motor 4mm ID “D” to ¼” OD
- Coupling: Polyurethane Tubing, ½” OD, ¼” ID.
- Coupling: Zip/cable Ties: 4”
- 75mm long ¼” steel shaft
- 35 mm long 3D printed pulley. 22mm diameter.
- Drilled with “D”0.246” drill to press fit on ¼” shaft
- 2 3D printed Pulley Holders.
- 2 Bushings: stock nylon shoulder spacers ½” Long, ¼” ID, 5/16” ID, ½” ID Flange
- 3 8” zip/cable ties hold on the gearbox bracket & pulley holders
Pulley end in ¾ MDF
- Same as motor side, except 60mm long shaft.
Pulley end in ¼” MDF:
- Pulley end ¼” is 60mm wide
- 1/8” steel shaft, 60mm long
- 4 ¼” diameter nylon spacers, 1/8” hole, ½” long, Center spacer has tape to make it crown.
- Wood is cutout for the pulleys
- Remaining wood is drilled 1/8”
- It’s pretty crude and fragile, but once it starts working I have yet to see fail.
- It’s easy to drill so the shaft is not straight. Then the belt walks to one side.
- In the pictures below the belt walked to one side anyway. It just did not matter.
Conveyor Belt:
- 30mm wide, 0.15mm thick Polyurethane
- Normally used for sealing fabric together, under garment strapping, etc.
- Sold as “TPU Tape” on Aliexpress.com
- Length wise sized 5% under
- Bonded together with a standard impulse heat sealer used for sealing poly plastic bags.
Speed Controllers:
- The first proof of concept had 24V power stepped down to 5 to 18 volts for the 12V motors with DC-DC LM2596 modules. This are really common, $1-2 on eBay, Amazon, etc. The system moving coins with motors running at 5-7 volts is surprisingly quiet with the coin hopper turned off.
