Project Sheet
Auger Lift #1

creation began 26 October 2020
completed 5 February 2021.

7 March 2021, the Case, and a Proximity Sensor
Auger Lift #1

The case has been completed.  In spite of the fact that I measured multiple times, it’s a tight fit.  The images show the case under construction.  Initially, I build a six-sided sealed container.  After it’s all glued together and the glue has had a bit of time to set I apply most of the coats of paint and then cut the case into a base and a top.  This particular case has 1/4″ bottom and top, and 1/8″ Baltic Birch plywood sides.

I am also in the process of creating a proximity sensor for this automata.  It will be the Proximity Sensors job to detect a human presence and then to turn on the automaton.  I am creating using the Arduino platform, which seems well suited for this application.  As I create the proximity sensor I am aware that I should probably be creating one for each of the automata that I build…so I’m using easily sourced components and am taking the time to create 3D printer files that can produce parts again and again as I need them.

The case for Auger Lift #1 is being primed with spray paint. 5 March 2021.
The case for Auger Lift #1 is being constructed. 4 March 2021.
The carrying case for Auger Lift #1 is being cut apart into a base and a top.

5 February 2021, All Done!
Auger Lift #1

Well, almost all done.  The automaton itself is completed and I’m very pleased.  I still need to construct the carrying case.

I really like the way that Auger Lift #1 turned out.  I love the metallic colors…and the color palette works well, at least to me.

The pinwheel gears were a mistake.  There is too much backlash in them.  The cam drives the driven pinwheel gear backward for just an instant.  If I create another auger lift I will be using black walnut bevel gears from Cranky Crab

Auger Lift #1 has been completely reassembled and now has about 46.5 hours on its clock.  It does not drop marbles (whew!).

About 6 pounds. 26 inches long, 13 inches wide, and 17 inches tall.




Auger Lift #1 is completed. 46.5 hours on the clock. 5 February 2021
Auger Lift #1 is completed. 46.5 hours on the clock. 5 February 2021

24 January 2021, Disassembled for Paint
Auger Lift #1

At the 43-hour mark, Auger Lift #1 was circulating marbles reliably.  It has been completely disassembled and is being painted at this time.

The painting process generally speaking is:

  • Sand to 180-220 grit.
  • Spray paint with grey automotive paint.  If necessary sand and re-spray.
  • Final coat(s) of spray enamel
  • Or more often acrylic hand-painted, many times two or more coats.
  • Auger Lift #1 has a lot of handpainted metallic acrylic paint.
  • Some components will be treated with paste furniture wax, usually several applications.

One of the keys to a good paint job is drying time.  I’m still not sure how long to let things dry.  That said I’m going to let Auger Lift #1 dry for 7 days.

On this automaton, I’m experimenting with applying thin coats of metallic paints so that components will have different hues of paint on them.

Auger Lift #1 components are being painted. 24 January 2021.


15 January 2021, Initial Build is Complete
Auger Lift #1

The initial build is completed.  Auger Lift #1 is successfully circulating marbles.  I finished it at about the 23 hour (hours of run time) mark, and am now letting it run as I do minor tweaks and as it selects its marbles.

I’m pleased with the build thus far.  Though occasionally throwing a marble off the track, all else is running smoothly.  The motor is absolutely silent, which is wonderful.  The entire unit is very stable.  The sound is hypnotizing.  The way the timing is working out is that about 1/2 second after each marble hits the end and falls onto the entrance rail…the next marble is released from the top…so there is motion virtually always.

The initial build of Auger Lift #1 is completed. January 12, 2021


9 January 2021, Construction of the Marble Run Rails
Auger Lift #1

I finished the marble run earlier today.  The run is composed of 1/32″ plywood strips held apart by about 90 3d printed spreaders.  The spreaders are superglued in place one at a time.  The resulting marble run is remarkably strong and very willing to maintain it’s shape.  My next attempt (for a future automata) may be to 3d print rail.  I’m going to experiment.

Now comes the “marble selection” process.  This is where the automata is run for many hours as it selects the marbles that it is happy with.  It’s remarkable how different 1″ Shooters are from each other.


Marble run rail assembly being created. 1/5/2021


3 January 2021, the Auger is Lifting Marbles
Auger Lift #1

The auger has been installed onto the Drive Frame.  Also, the entrance and exit ramps have been created.

When I constructed the auger lift test stand I had noticed that the motor was very loud.  It was a 14-watt gear motor.  In this automata I’ve installed a smaller 6 watt motor.  It’s absolutely silent.  I think it will be fine.  The loads are very light. And while I had thought that a 20 rpm motor would be fine, this 10 rpm motor is even better.

The next step for this automata will be the actual creation of the marble run.

Barely peeking out at the lower part of the picture you can see portions of the electrics pane.  This panel contains an on-off switch, a 3 amp circuit breaker, and an hour meter.


The auger has been installed. 3 January 2021.


19 December 2020, Creating the final Elliptical Pedal module
Auger Lift #1

I’ve tested the auger and I’ve tested the elliptical pedal assembly.  The next step is the actual creation of the modules.

The first module that I have created is the Elliptical Pedal module.  This module is self-contained and easily removable from the Drive Frame.  This is important because the Drive Frame will contain both the auger lift and the marble run.  I don’t want the Elliptical Pedal module to get in the way…and I want it to be easily removed for servicing.

The biped is attached via gravity (he sits on a rod) and via magnets (wrists and feet).  He is very easy to remove.

The motion is smooth.  He both pedals, and his torso moves slightly up and down as he pedals.

No motor…the motor is contained in the drive frame.


The Auger Lift biped is installed onto the elliptical pedal module. This module will be driven by the Drive Frame. 19 December 2020.


The Elliptical Pedal module and the drive frame. 19 December 2020.

9 December 2020, Elliptical Pedal Test Stand
Auger Lift #1

The Auger Test Stand has been dismantled.  As I began creating the full automata I decided that I needed to build an Elliptical Pedal Test Stand…just to be sure that everything is going to work smoothly and as envisioned.  I’m pleased to report that it works beautifully.  You can watch a video here.

One thing that I’ve learned is that the 14 watt gear motor that I thought I would be using is not quiet.  I’m considering using a smaller motor.  And where I thought I would not need ankle joints, I found it do need them.  I’ve used leather.

The mechanism is very smooth and quiet (except for the motor).  The 3D printer is a large part of the puzzle.  Because I’ve 3D printed things the parts are more uniform, thus there is less binding and stress.  So, quieter.

Now for the pleasurable task of turning these mechanical assemblies into a work of art.


Elliptical Pedal Test Stand. 8 December 2020


18 November 2020, Auger Lift Test Mechanism
Auger Lift #1

I will be using several different mechanisms in Auger Lift #1 that I’ve not used before.  When I get into this kind of situation I build a “Proof of Concept” machine.  In the POC machine, I marry rough creations of the different mechanisms to see how they work individually and how they work in concert with each other.

In the image to the right is a 20 rpm motor driving through Pinwheel Gears to a long auger.  At the top of the tower is what I call a marble tipper mechanism.

What I’ve learned from this so far:

  • The plastic hubs don’t work at the motor.  The motor shaft gets too hot and the hub starts to slip on the shaft.  Metal hubs are the solution.
  • A 20 rpm drive motor is a perfect speed.  Going into this project I was planning on using a 10 rpm motor.
  • The auger lifts well, however, the auger and the piece that holds the marble into the auger must be firmly related to each other.  In this particular creation, there is some slop, which causes the marbles to occasionally jump out.
  • The marble tipper at the top does not behave the way that I had envisioned.  It moves too quickly.  I’m in the process of trying to slow down the motion.  I think magnets will be part of the solution.,
  • I am going to lean the auger a little further toward the horizontal.



Auger Lift #1 Proof of Concept mechanism. 18 November 2020.


4 November 2020, Creating the Head
Auger Lift #1

This is the first time that I’ve created a head using these methods…and is probably not the last.  The top image shows me applying a wood filler over the 3D printed armature.  The lower image shows the head nearer the final stage of creation.  Note the 3D printed ears.




Auger Lift #1 head armature is receiving it’s skin. 2 November 2020.
Auger Lift #1 head, before and after (though not yet completed). 4 November 2020

30 October 2020
Auger Lift #1

Key to all of the automata that I create are the bipeds.  They are important.  I spend quite a bit of time creating these little creatures, with my techniques improving with each one.

I’ve consistently had trouble with the heads…getting the proportions ‘sort of right’.  And of the head detail, it is the ears that cause me the most angst.

The addition of a 3D printer to my set of tools permits me to get outside of the space that I’ve been in.  For example, pictured to the right, you see a skull armature.  I 3D printed this armature and will coat it with skin and detail.  Also to the right you see a 3D printed ear.  What a relief to be able to have my little shop assistant create these things for me.

This particular biped has 3/16″ joint pins.  I’ve not yet stabilized on a consistent way to create joints.

The biped is being created for Auger Lift #1. Note the 3D printed skull armature. 30 October 2020.
A 3D printed Left Ear. November 1, 2020

26 October 2020
Auger Lift #1

Auger Lift #1 is a member of the Jim’s Gym family of automata.  It is in the process of being created.

Going into the project it is envisioned that a biped will be operating an elliptical sort of exercise machine, which will in turn power an auger, which will raise marbles up about 15”.  The marbles will then roll back to the bottom for recycle.

I recently purchased a Prusa Mini, a 3D printer.  This is the first automata that I will attempt to use it with.

As I consider the creation of Auger Lift #1 there are many different aspects to think about.  At this moment I am considering how the marbles will drop back down once they have rolled over the top. Pictured at the right is a tipper assembly.  The marble will roll in at the top and the tipper will rotate it to the bottom.  I envision a counterbalance that will cause the motion to be slow and graceful.

Before I further develop the tippers I want to get the marbles to the top.  Then I’ll know what I need to do (I’ll know where the bottom is).


A 3D printed tipper disc axle. 26 October 2020
A marble tipper assembly that is being considered for use in Auger Lift #1. 27 October 2020.