Starting Point: Components for the motor shaft assembly.
End Result: Motor shaft, pulley and codewheel fully assembled.
- this page describes how to prepare the the motor shaft assembly for the brushless actuator modules
- the aluminum motor pulley and the stainless steel motor shaft are bonded with Loctite 648
-> Bonding the Pulley to the Motor Shaft - the code wheel mount is installed and the code wheel is bonded to the mount
-> Bonding the Codewheel
- More information on the 3d printing: Details 3d Printed Parts
- More information on the machined part: Details Machined Parts
- PDF Drawing - Motor Shaft
- PDF Drawing Motor Pulley
- STL File - Codewheel mount for code wheel ordered from PWB
- STL File - Codewheel mount for code wheel from kit
- STL File - Tool Motor Shaft Pulley Bonding
- STL File - Tool Code Wheel Bonding
Motor shaft, motor pulley and tool for motor shaft bonding.
Make sure that the tool supports the pulley in the right position before bonding.
Measure the depth of the tool using the depth gauge of a digital caliper.
The depth should be around 6,6mm.
The distance between the tool and the end of the motor shaft should be about 26,8mm.
Clean the bonding surfaces with a cotton swab and ethanol.
Prepare some Locitite 648, tooth picks and cotton swabs.
Wear gloves to protect your skin.
Apply a thin layer of Locitite 648 onto the bonding surfaces.
Insert the motor shaft into the pulley and rotate it a bit.
Remove the excess Loctite from the bottom using a cotton swab.
Place the motor shaft and pulley on the bonding tool.
Make sure that the flats on the motor shaft are pointing upwards.
Remove the excess Loctite from the top using a cotton swab.
Make sure that the motor shaft vertical and fully inserted into the tool.
Let the parts cure at room temperature for a couple of hours.
Leave the parts on the tool, put them in an oven.
Cure the bond for another couple of hours for full strength.
We cure the parts at 70 degrees celcius for about 3 hours.
The motor shaft and pulley assemblies are now ready and can be used for the next step.
Code wheel, code wheel mount, motor shaft with pulley and bonding tool.
There are two different sources for the code wheel.
A: Code wheel ordered from PWB / B: Code wheel from encoder kit.
Make sure to use the corresponding code wheel mount stl file.
A: Codewheel mount for code wheel ordered from PWB
B: Codewheel mount for code wheel from encoder kit
All the other assembly steps are identical.
Place the code wheel on the code wheel mount and make sure it fits before you apply glue.
Make sure that the code wheel is fully seated, flat and doesn't wobble when you turn it.
Sometimes the codewheel doesn't sit flat on the surface because of residue from the 3d printing.
Use a flat screw driver to scratch off the residue from the corner of the part.
I find it easiest to bond the code wheel on the stator.
Insert the motor shaft with the flats downwards into the bearings of the stator.
Adjust the inner diameter of the codewheel mount with a 4mm reamer.
Place the code wheel mount on the motor shaft and align the teeth of the pulley and the mount.
Push the code wheel mount all the way down.
Check the distance between the end of the motor shaft and the mount.
The distance should be around 2mm - it's fine if it's off by 0,1 or 0,2mm.
Prepare your code wheel with the print facing upwards.
Prepare the superglue, tooth pick, q-tipps and the bonding tool.
Use gloves to protect your skin from the superglue.
Important: The code wheel has to be mounted in the correct orientation.
The print on the code wheel has to be readable from the top as shown in the picture.
Apply a thin layer of superglue to the code wheel mount.
We use Loctite 406.
Place the code wheel on the mount and push it all the way down using the tool.
Hold for 30 seconds, gently remve the tool and wait a couple of minutes for the glue to cure.
Code wheel bonded to the code wheel mount.
Rotate the motor shaft and make sure that the code wheel is horizontal and doesn't wobble.
Remove the motor shaft assembly from the stator.
The motor shaft assembly is now ready for installation.
| Motor Preparation | Motor Shaft Preparation | Encoder Preparation | Center Pulley Preparation |
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| Output Pulley Preparation | Shell Preparation | Actuator Module Assembly | Actuator Module Testing |
|---|---|---|---|
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| Details 3d Printed Parts | Details Machined Parts | Mechanical Tools and Consumables | Electronic Components and Tools |
|---|---|---|---|
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Felix Grimminger
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