CNC Operator Skin for Prusa CORE One

CNC Operator Skin for Prusa CORE One

Turn your Prusa CORE One into a small industrial-style CNC operator cell.

This project is a complete visual skin kit inspired by CNC machine control stations. It adds an external operator panel, side arm, nozzle tool rack, status light and corner guards while keeping the printer fully usable.

The idea was to create something that looks like a real machine upgrade, not just a decoration — but still make it easy to print, assemble and customize.

What is included

The kit includes:

• CNC-style operator panel

• movable side arm and printer mount

• nozzle tool rack / tool library

• decorative status light

• corner guards

• printable HMI screen graphic

• optional print-only panel body

• test-fit button parts

• optional arm mount alignment tool

• prepared 3MF print plates

Main features

• Designed specifically for Prusa CORE One

• Support-free printing — no supports required

• Parts are split by color and function

• Prepared STL and 3MF files included

• Manual filament changes can be used for raised icons and text

• Operator panel can be built with or without acrylic

• Does not block the door, controls, ventilation or print volume

• No electronics required

• Non-permanent installation

• Designed from scratch in CAD

Operator panel

The operator panel is the main part of the kit. It is a CNC-inspired pendant with a printed HMI screen, physical-looking buttons, jog wheel and decorative E-stop.

Two panel body versions are included:

Acrylic version

Recommended version.

Uses a printed HMI graphic under a clear acrylic / plexiglass sheet:

• Acrylic / plexiglass size: 150 × 150 × 3 mm

This gives the screen a more realistic industrial HMI look.

Print-only version

For users who do not have acrylic.

This version has a shallow 0.15 mm recess for the printed HMI graphic / sticker. The rest of the panel assembly stays the same.

HMI graphic

A printable HMI screen graphic is included.

Print it at 100% scale.
Use the included A4 print sheet with crop marks and the 100 mm scale check line.

Important print settings:

• Print at 100%

• Use Actual Size

• Disable Fit to Page / Scale to Fit

• Check the 100 mm scale line after printing

Nozzle tool rack

The side tool rack is inspired by a CNC tool library.

It is labeled as a nozzle library:

• T1 — 0.25

• T2 — 0.30

• T3 — 0.40

• T4 — 0.50

• T5 — 0.60

• T6 — 0.80

It adds a practical and visual “tool magazine” detail to the printer.

Status light

The status light is decorative and does not require electronics.

It is printed as one part and can be made with manual filament changes.

In this build, the status light is mounted using double-sided tape.

Corner guards

The corner guards are small orange accent parts that complete the industrial machine look.

They can be mounted in two ways:

• with double-sided tape

• with magnets embedded during printing

If you want to use magnets, add a pause in the slicer at the magnet pocket height, insert the magnets, and then continue the print.

If you do not want to use magnets, print them normally and mount them with double-sided tape.

Printing notes

All parts are designed to print without supports.

Suggested colors:

• Black / dark graphite — main parts

• Orange — Prusa-style accents

• White — raised icons and text

• Red + yellow — E-stop

• Green / yellow / red / black — status light

Manual filament changes

Some parts are designed for manual filament changes on a single-material printer.

This applies especially to:

• button icons

• lower faceplate text

• status light color sections

• nozzle tool rack labels

Print the base color first, then pause and change filament for the raised text or icon layers.

Prepared 3MF files are included to make this easier.

Hardware and additional parts

You may need:

• 150 × 150 × 3 mm acrylic / plexiglass sheet

• M3 heat-set inserts

• M4 heat-set inserts

• M3 screws

• M4 screws

• nuts for the printer-side mounts

• double-sided tape

• optional magnets for corner guards

Heat-set inserts for the operator panel

The file CORE_One_CNC_panel_body.stl uses 12 heat-set brass inserts in total.

Front side:

• 4 × M4 heat-set inserts
  Hole diameter: Ø6 mm
  Hole depth: 6.2 mm

• 4 × M3 heat-set inserts
  Hole diameter: Ø5 mm
  Hole depth: 8.2 mm

Rear side:

• 4 × M4 heat-set inserts
  Hole diameter: Ø6 mm
  Hole depth: 7 mm

Suggested screw length rule:

screw length = insert hole depth + approx. 2 mm

Typical screw ranges:

• M3 screws: M3x10–M3x12

• M4 screws: M4x8–M4x10

Exact screw length may depend on the inserts and screws you use.

Test-fit parts

Button test-fit parts are included:

• CORE_One_CNC_panel_test_fit_button_socket.stl

• CORE_One_CNC_panel_test_fit_button.stl

The test-fit button currently has 0.2 mm clearance on the length.

Print these first if you want to check your printer tolerance before printing the full operator panel. If the fit is too tight or too loose, adjust XY compensation / horizontal expansion in your slicer.

Optional alignment tool

An optional alignment tool is included:

• CORE_One_CNC_arm_mount_alignment_tool.stl

It helps hold the nut in position from inside the printer while tightening the mount screw from the outside.

This tool is only used during assembly and is not part of the final installed kit.

Important installation notes

The printer-side mounts use screws from the outside and nuts from the inside of the printer. This keeps tool access on the outside and makes installation easier.

Important:
The screw must not protrude more than 9 mm inside the printer.

If the screw sticks out more than 9 mm inside the printer, the Z-axis bed mount may collide with it during movement.

After installation, always check that:

• the door opens correctly

• the bed can move freely

• ventilation is not blocked

• the print volume is not affected

• all parts are mounted securely

Disclaimer

This is a decorative / visual CNC-style skin kit.
It does not modify the printer electronics and the operator panel controls are decorative.

Always check clearances after installation before running the printer.

Operator Panel Assembly

Step 1 — Prepare the panel body

Start with CORE_One_CNC_panel_body.stl.

This is the main body of the operator panel.

Step 2 — Install the front heat-set inserts

Make sure the inserts are seated straight and flush with the surface.

Step 3 — Install the rear heat-set inserts

Turn the panel body over and install the rear heat-set inserts.

These inserts are used for mounting the panel to the arm.

Step 4 — Install the orange side accents

Press the two orange side accent pieces into the side slots of the panel body.

Files:

• CORE_One_CNC_panel_side_accent_left.stl

• CORE_One_CNC_panel_side_accent_right.stl

They are decorative accent parts and should sit flush with the front frame.

Step 5 — Install the buttons, jog wheel and E-stop ring

If you printed the test-fit parts and everything was correct, it should fit. If not, you can use glue.

The buttons, jog wheel and E-stop are decorative elements and do not connect to the printer electronics.

Step 6 — Install the red E-stop button

Press the red E-stop button into the yellow E-stop ring.

File:

• CORE_One_CNC_panel_estop_button.stl

If you printed the test-fit parts and everything was correct, it should fit. If not, you can use glue.

Step 7 — Prepare the screen parts

Prepare the screen frame parts:

• CORE_One_CNC_panel_screen_insert_orange.stl

• CORE_One_CNC_panel_screen_frame.stl

The orange screen insert sits around the visible HMI graphic.
The black screen frame holds the acrylic / plexi sheet mechanically from the front.

Step 8 — Install the HMI graphic and acrylic sheet

Place the printed HMI graphic into the screen pocket.

For the acrylic version, place a clear acrylic / plexiglass sheet on top of the graphic:

• Acrylic / plexiglass size: 150 × 150 × 3 mm

Print the HMI graphic at 100% scale. Disable “fit to page” or “scale to fit” when printing.

Step 9 — Install the black screen frame

Place the black screen frame over the display area and secure it with screws.

File:

• CORE_One_CNC_panel_screen_frame.stl

Step 10 — Prepare the lower faceplate

Prepare the lower faceplate.

File:

• CORE_One_CNC_panel_lower_faceplate.stl

The raised text and details can be printed using manual filament changes - just use 3mf file. 

Step 11 — Install the lower faceplate

Attach the lower faceplate to the front of the operator panel and secure it with screws.

Mounting the Arm to the Operator Panel

Step 12 — Prepare the arm / panel mount

Prepare the printed arm part.

File:

• CORE_One_CNC_arm_panel_mount.stl

Step 13 — Attach the arm to the rear side of the panel

Place the arm on the rear side of the assembled operator panel and secure it using screws.

Use the rear M4 heat-set inserts installed earlier in the panel body.

Make sure the arm is aligned correctly before tightening the screws.

Do not overtighten the screws. The arm should sit flat against the back of the panel and hold the panel firmly.

The operator panel is now ready to be installed on the printer-side mount.

Nozzle Tool Rack Assembly

Step 14 — Prepare the nozzle tool rack parts

Prepare the nozzle tool rack parts.

Files:

• CORE_One_CNC_tool_rack_nozzle_holder.stl

• CORE_One_CNC_tool_rack_orange_strip.stl

The nozzle holder is labeled as a small CNC-style tool library:

• T1 — 0.25

• T2 — 0.30

• T3 — 0.40

• T4 — 0.50

• T5 — 0.60

• T6 — 0.80

The raised labels can be printed using manual filament changes.

Step 15 — Install the orange accent strip

Press or slide the orange accent strip into the side channel of the nozzle tool rack.

Printer Preparation

Step 16 — Move the print bed up

Before installing the mounts, move the print bed all the way up.

This gives you more space and better access to the inside of the printer during installation.

Step 17 — Remove the four factory plastic rivets

Remove the four factory plastic rivets from the printer side panels.

There are four rivets in total:

• 2 rivets on the right side

• 2 rivets on the left side

Use the first photo to show the rivet locations with arrows.
Use the second photo to show the mounting points after the rivets have been removed.

The rivets can be gently lifted with a thin flat tool or small screwdriver and should come out without much force.

Be careful not to scratch the printer frame or side panels.

Repeat the same operation on the opposite side of the printer.

Keep the rivets in case you ever want to return the printer to its original state.

Step 18 — Install the printer-side mounts

Install the two printer-side mounts using screws from the outside and nuts from the inside of the printer.

Files:

• CORE_One_CNC_arm_printer_mount.stl

• CORE_One_CNC_tool_rack_mount.stl

To make installation easier, use the optional printed alignment tool.

File:

• CORE_One_CNC_arm_mount_alignment_tool.stl

Press the nut into the alignment tool and hold it against the inside of the printer

Mounting sequence:

1. Place the printed mount on the outside of the printer.

2. Insert the screw from the outside through the mount and into the printer frame.

1. Hold the screw from the outside with an Allen key or screwdriver

2. From the inside of the printer, place the nut and alignment tool onto the protruding screw.

1. Turn the screw from the outside until it catches the nut.5

2. Tighten the screw carefully while keeping the nut aligned with the tool.

1. Remove the alignment tool after tightening.

This keeps tool access on the outside of the printer, which makes installation much easier.

Important clearance note:

The screw must not protrude more than 9 mm inside the printer.

If the screw sticks out more than 9 mm inside the printer, the Z-axis bed mount may collide with it during movement.

Before continuing, manually check that there is enough clearance between the screw end and the Z-axis bed mounting parts.

Repeat the same mounting process on the opposite side of the printer for the nozzle tool rack mount.

Installing the Operator Panel on the Printer

Step 20 — Install the operator panel arm onto the printer mount

Install the assembled operator panel with the arm onto the printer-side arm mount.

Start by placing the lower part of the arm onto the printer mount first.

Then slide the upper part of the arm in from the side, using the chamfered area as the entry point.

Make sure the arm moves into position smoothly and does not force the mount sideways.

The arm is now installed and can be moved into the desired operator panel position.

Installing the Nozzle Tool Rack on the Printer

Step 21 — Slide the nozzle tool rack onto the printer-side mount

Take the previously assembled nozzle tool rack and install it onto the tool rack mount on the opposite side of the printer.

Step 22 — Install the corner guards

Install the printed corner guards on the printer corners.

Files:

• CORE_One_CNC_corner_guard_magnet_ready.stl

The corner guards can be mounted in two ways:

• with double-sided tape

• with magnets embedded during printing

If you want to use magnets, print the magnet-ready version and add a pause in the slicer at the magnet pocket height. Insert the magnets during the pause, then continue the print. The magnets will be embedded inside the corner guard.

If you do not want to use magnets, simply print the corner guards normally and mount them with double-sided tape.

Mounting sequence:

1. Clean the printer corner surface.

2. If using magnets, make sure they were embedded during printing.

3. If using tape, apply double-sided tape to the inside of the corner guard.

4. Align the corner guard with the printer corner.

5. Press it gently into place.

Step 23 — Install the status light

Install the printed status light on top of the printer.

File:

• CORE_One_CNC_status_light.stl

In this build, the status light is mounted using double-sided tape.

Mounting sequence:

1. Clean the top surface of the printer.

2. Apply double-sided tape to the bottom of the status light.

3. Place the status light on top of the printer.

4. Press it gently into place.

5. Make sure it does not block ventilation openings.

Assembly is complete.

The CNC Operator Skin is now installed on the Prusa CORE One.
Before using the printer, check that the door opens correctly, the bed can move freely, ventilation is not blocked, and all mounted parts are secure.