T3P3 Kossel Mini Kit

Assembly Instructions -

Chapter 22 - LCD Controller

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Think3DPrint3D Ltd


2201 Bill of materials

PanelOne circuitboard (supplied assembled)

M3 x 25 x4

M3 x 8 x2

M3 full nut x6

The printed parts required for the PanelOne assembly will be printed during step 2204.

The PanelOne controller is supplied assembled  and tested, with two 10-way ribbon cables labelled AUX2 and AUX3 to connect it to the RAMPS board.

NOTE: This picture shows Version 1 of the PanelOne with the micro-SD card reader on a small separate PCB. In mid-July 2014 we changed to Version 2 of the PanelOne which has the card reader fitted directly to the main PCB.

If your PanelOne looks this ------------------->

then you have Version 2. There is no functional difference between V1 and V2, but the encoder position has been moved downwards, and so the files for printing the case are slightly different. Files for both versions are supplied on the SD card and V2 files are also on Github.

2202 Connect controller

Plug the cables onto the labelled AUX2 and AUX3 connectors on the PanelOne PCB with the red stripes on the left side of the cables.

If you have not already attached the other end of the cables to the RAMPS you will need to remove the printbed to do so now. Identify the AUX2 and AUX3 connectors at the bottom right corner of the RAMPS board.

Attach the cables as shown, with the red stripes on the left.

NOTE: The position of AUX2 and AUX3 is opposite to that on the PanelOne, on which AUX2 is on the right and AUX3 on the left. Double-check that you have them correct

You can hide any excess length of cable inside the printer base.

Power up the printer with the USB cable detached. The display should light up and display the main menu showing the printer status.

NOTE: These pictures were taken on a prototype using a dark-blue on light-blue display. LCDs supplied with kits are white-on-blue instead.

2203 Explore and Test

The controller is operated by the twist-and-press rotary encoder to the right of the LCD screen. G-code to be printed  is read from the micro-SD card slot projecting up from the top of the PCB. The brightness and contrast trimmers are pre-set and will probably not need adjusting.

The Marlin LCD menu tree is in a file named LCD Menu Tree.pdf in the Marlin folder.  It is too big and detailed for us to cover the whole tree in this manual, so we will concentrate on the parts needed for straightforward printing only.

The first-level menu appears when the encoder is pressed once.

Only 4 lines at a time appear on the LCD. Some of the menu items will only appear under certain conditions - for example, Pause print, Resume print and Stop print will only appear if the printer is actually printing.

Rotate the encoder knob to move the selection arrow down onto the Prepare menu.  The menu tree shows all possible options, but those of interest here are:-

  • Main - back to Main menu
  • Disable steppers
  • Auto home
  • Preheat PLA
  • Cooldown


Try them out.

 Auto home should home the axes.

Preheat PLA should set the hotend to the PLA temperature set in Marlin - in this case 210C

The only Control menu option covered here is Temperature

Select the Temperature option by rotating the encoder till the arrow points at it, and press the encoder.

The Temperature control menu appears. Select Nozzle and press the encoder.

Rotate the encoder to turn the nozzle temperature up or down - in this case down to zero. Press the encoder to set this, and the display will revert to the previous screen.  You can then select Main to revert, by stages, to the main menu, or just leave the controller to do so automatically after a short delay.

You should familiarise yourself with other menu options, guided by the LCD Menu tree. For example, moving axes in the Prepare menu.



2204 Print from LCD Controller

The main purpose of the LCD controller is to print directly from micro-SD card, without the need for a PC attached by a slow USB connection.

 For this  section we will use the example of printing a case for your PanelOne LCD controller.  You will need to slice the PanelOne .stls supplied on the SD card as part of your kit, using the Draft Slic3r profile.  

Slice each in turn, saving them to SD card.

         Files to slice:-

  • PanelOne_knob.stl
  • PanelOne_case_back_v3.stl
  • PanelOne_case_front_v3.stl
  • PanelOne_case_mounts.stl

The SD status appears on the first level down from the Main menu on the LCD tree.

In this case no SD card was present when the printer was powered up.

Insert the SD card with the G-code files loaded, and select the next option down - Init SD-card.

Select the file to print and click the encoder. We chose the PanelOne controller knob as a small quick test.

Pix required -select file etc

The print starts. The controller tells you:-

  • The extruder temperature
  • The tip position in X, Y and Z
  • The print speed - which can be altered during printing by rotating the encoder.
  • the % of the file printed
  • The printing time elapsed

When the print finishes the printer will home itself, and you can remove the print and skirt.

The controller tells you it took 7 minutes.

Next try the legs.  They took 19 minutes.

After that, print the PanelOne case back. Remember to watch the start of the print and remove the puddle of PLA produced by priming the nozzle right away. It will be hot, so use tweezers or similar. If you don’t do this …….

….. the print will go over it.

The case back is quite a long print, at 1 hour 3 minutes. Your time may vary as this was printed using different Slic3r settings.

Big flat prints can be hard to remove from the printbed. We use a sharp chisel  to get under a corner and lift.  DO THIS AT YOUR OWN RISK AND BE VERY CAREFUL!

Finally, the case front. Under way…..

and finished in 1 hour 38 minutes Remove as for the back.

Completed  PanelOne case parts

2205 Assemble and fit

Check the fit of the case front over the LCD - you may have to remove some first-layer flash from the LCD opening and encoder hole.  

[to follow]

Add the case back and the mounts and fasten with 4 M3 x 25 socket capscrews and 4 M3 full nuts.

[to follow]

Insert 2  M3 full nuts in the top channel of the X-Y  base upper extrusion, align and fix the PanelOne case to the base with 2  M3 x 8 capscrews.

This concludes the final stage of printer assembly.  Happy printing!