Build - Electronic Lead Screw

This is a place-holder page for a future project.

Project Box for LED&KEY PC Board (3D Printed)

[March 2020]

I created this project box for Control Panel. The print files for this can be downloaded from here:

https://www.prusaprinters.org/prints/24616-project-box-ledkey-pc-board-electronic-lead-screw

My design was based in part on clough42 3D prints from his project, but I made extensive changes as I will be using the box for my project, whereas clough42 switched to a metal box.

All of the 3D printing was done with my recently purchased Prusa Mk3/S printer.

The project box is designed with a built in hole for the GX-16 connector; the front panel (box lid) fastens with screws from the back. The LED&Key board mounts to stand-offs on the back of the panel. A spacer piece is used to help sandwich a red filter between the board and lid; the spacer also serves to "tunnel" the LED lights to the front panel. For the red filter, I used "tail-light tape" and a piece of white paper as a diffuser over the digits.

3D printed box

3D printed panel and spacer

Red filter with paper diffuser

Both the box and the internal mounting of the board are done with #4 x 3/8" sheet metal screws; these screw into plastic stand-offs built into the lid. All screws mount from the rear,so ther are no screw visible on the front panel.

Red "tail-light" tape

Screws for box and panel

I created multiple panel (box lid) options. The one I am using is shown to the left,with 3D printed text included. The text is created by switching filaments during the printing process. The panel is printed face down with the text "cut out" of the first layers. The first layers are printed with black filament, then the print is paused ans switched to white filament. Two layers of white filament are printed, and then the filament color is switched back to black.

The resolution limits of the printer (with the .4mm nozzle I an currently using) requires the text to be fairly large, but this is actually an advantage in this case as it improves readability in use.

I also re-designed the buttons in two ways (not shown). First, I thinned the "web" holding the buttons together (to make it more flexible). Second, I elongated the buttons a bit, and tapered the tops more to make them more accessible.

Preparing the ELS Boost Interface Board

The board as provided requires some components to be soldered on.

Steps are as follows:

1. Solder on power connector

  • Apply power
  • Check for LEDs (3.3V, 5V) to light up
  • Check power readings to confirm

2. Solder on servo/stepper driver connector strip (6-pin servo connector)

  • Strip on top, solder from bottom

3. Solder on 5-pin header

  • Header on top, solder on bottom

4. Solder on two (2) 2×10 female header connectors

  • Headers on bottom, solder on top

Preparing the TI-Launch Board

To make the TI LaunchXL-F280049C circuit board easier to handle, and also to eventually mount it in a project box, I 3D printed a board mount (see photos below):

Board in mount

Bare mount

Mounted board - bottom side

Set jumpers and switches :

  • Move Switches S3 and S4 to the positions shown to enable the EQEP1 encoder input. You will need to peel the Kapton tape off the switches to access them.
    • Move both S3 switches toward "QEP Select
    • Move S4 away from "35/37 Route"
  • Remove the USB power jumpers (JP1/JP3/JP3) to isolate the USB port from the ELS power supplies

References:

My 3D prints:

Clough42 provided 3D print files for his project, but I went in a different direction and made extensive changes:

This build is based on the Electronic Lead Screw project by Clough42 on youtube. See references to that project below:

Here is the site playlist : Lathe Electronic Leadscrew Playlist

Annotated playlist:

  1. Lathe Electronic Leadscrew Part 1: Proof of Concept
    • Discussion of selection of hardware and other considerations.
  2. Lathe Electronic Leadscrew Part 2: Gear Ratio Calculations
    • Discussion of mathematical calculations required in the programming for various threads and gear ratios.
  3. Lathe Electronic Leadscrew Part 3: Control Panel and Debugging
    • Why the 7-segment LED control panel was selected, and considerations for use. Includes a discussion of the 3D printed front panel and flexible buttons.
  4. Lathe Electronic Leadscrew Part 4: Steppers and Servos and Drives (Oh My!)
    • ". . .looking at stepper and servo motors, the differences between them and how to interface them to a microcontroller. We'll also talk about which might be the best fit for the Electronic Leadscrew."
  5. Lathe Electronic Leadscrew Part 5: Mounting the Encoder and Servo on the Lathe
    • ". . .starting to put the electronic leadscrew components on the lathe. We'll talk about timing belt drives for both the encoder and the stepper or servo, we'll make mounting brackets and get this thing ready to actually run."
  6. Lathe Electronic Leadscrew Part 6: First Test Cuts!
    • ". . . we're making our first cuts with the electronic leadscrew. In steel. We test out the various feed rates at different depths and try cutting a couple of different threads." Testing both the stepper motor and servo motor.
  7. Lathe Electronic Leadscrew Part 7: Metric Threading FTW!
    • Modifying and installing the toothed pulleys. Cutting metric threads. Cutting left hand threads. Note that this is metric threading with a non-metric leadscrew.
  8. Lathe Electronic Leadscrew Part 8: PC Board Assembly
    • Assembling and testing prototype PC board.
  9. Lathe Electronic Leadscrew Part 9: Machining a Control Panel
    • CNC machining of the control panel (CU-124 Aluminum Econobox, 4-23/64" Length x 2-23/64" Width x 1-13/64" = 110mm L x 60mm W x 30mm D) [Also - 3D printed buttons and spacer.]
  10. Lathe Electronic Leadscrew Part 10: How to Program a TI LaunchPad Microcontroller
    • ". . . how to program the TI LaunchPad microcontroller used in the Electronic Leadscrew. We'll start with a fresh install of Windows, install the TI Code Composer Studio (CCS) IDE, download the source code from GitHub and program the controller." How to set the switches and jumpers. Includes extensive instructions on how to install the IDE and download the firmware. Includes how to set #defines and install the firmware.
  11. Lathe Electronic Leadscrew Part 11: Metric Leadscrew Support
    • ". . . metric leadscrew calculations and how to configure the code for your lathe." This is for use on a lathe with a metric leadscrew.
  12. Lathe Electronic Leadscrew Part 12: PCB Manufacturing Update
    • Progress update. How to solder the components onto the PCB.
  13. Lathe Electronic Leadscrew Part 13: Assembling a Bed-Of-Nails PCB Test Fixture
    • "In preparation for selling PC boards for the electronic leadscrew, I'm putting together a bed-of-nails (POGO pin) test fixture so I can test the boards without soldering on connectors. I show how I aligned the pins and got them all to the same height to mesh properly with the board under test.
      • I tried a few different kinds of solder and flux before finding a combination that worked properly."
  14. Lathe Electronic Leadscrew Part 14: Testing and Packaging PCBs
    • "Today I show how I test the PC boards, count our the connectors for the kids and package them for sale."
  15. Lathe Electronic Leadscrew Part 15: Sold-Out PCBs and Documentation
    • "Wow! The 100 PC boards I ordered sold out in 2.5 hours. I've ordered more, and I'll let you know when they arrive. In the mean time, let's look at the documentation."
  16. Lathe Electronic Leadscrew Part 16: Building the Electronics Enclosure
    • "Today we're going to build a proper electronics enclosure for the electronic leadscrew. We'll use a NEMA1 Hammond box, DIN rail and some really cool 3D-printed parts [DIN rails, fan grid, connector panel]."

Documentation:

Code Composer Studio IDE download : https://www.ti.com/tool/CCSTUDIO-C2000

C2000 Piccolo MCU F280049C LaunchPad™ development kit : https://www.ti.com/tool/LAUNCHXL-F280049C

3D printed pieces from clough42 : https://www.thingiverse.com/thing:3740612