Marine Radio Room Clock – Multicolor Wall Clock with 24-Hour Markings

A 3D-printable replica of a classic marine radio room clock, featuring the traditional red and green radio-silence sectors, 12-hour and 24-hour markings, an integrated quartz movement holder, and a rear keyhole wall mount.

The clock is printed as a single main part using manual filament changes on a single-extruder printer.

About the dial

Traditional marine radio room clocks used colored sectors to indicate scheduled radio-silence periods, allowing weak maritime distress calls to be heard:

• Red sectors: 500 kHz radiotelegraph silence periods

• Green sectors: 2182 kHz radiotelephone silence periods

More information about radio silence and radio room clocks:

Radio silence – Wikipedia

The alternating red and white markings around the outer edge are also based on the traditional radio room clock design.

Features

• Replica of a traditional marine radio room clock

• Large 1–12 hour markings

• Smaller 24-hour markings

• Four-color printed dial

• No painting, stickers, or separate number inserts required

• Integrated snap-fit holder for a standard quartz movement

• Integrated rear keyhole wall mount

• Designed for manual filament changes on a single-extruder printer

Dimensions

• Outer diameter: 210 mm

• Dial diameter: 200 mm

• Printed body depth: 22.4 mm

• Approximate total assembled depth: 36 mm

Required hardware

Quartz clock movement

The prototype uses a standard silent quartz wall clock movement, similar to the movement shown in the photos. The movement shown in the photos is marked 5168-S, but dimensions may vary between visually similar movements.

Reference dimensions:

• Movement body: 56 × 56 mm

• Total shaft projection from the movement body: 18 mm

• Threaded section length: 6 mm

• Power: 1× AA battery

The movement snaps directly into the integrated rear holder. The movement’s mounting washer and retaining nut are not used.

Clock movements that look nearly identical may have different body or shaft dimensions, so check the measurements before ordering.

Suggested search description:

56 × 56 mm silent quartz wall clock movement, 18 mm total shaft, 6 mm thread

Clock hands

The prototype uses the following hand lengths, measured approximately from the center of rotation to the tip:

• Hour hand: 59 mm

• Minute hand: 83 mm

• Second hand: 90 mm

Similar or shorter hands should also fit, provided they are compatible with the selected movement.

Printing

The supplied 3MF project was prepared using:

• Material: PETG

• Nozzle: 0.4 mm

• Layer height: 0.20 mm

• Perimeters: 3

• Infill: 15%

• Supports: not required

• Approximate filament use: 134 g

• Approximate print time: 5 hours 23 minutes

• Number of manual tool changes: 7

Print time and filament consumption will vary depending on the printer and selected profiles.

Build plate finish

The clock is printed with the dial facing the build plate. The build plate surface therefore becomes the visible finish of the clock face.

For the best result:

• Clean the build plate carefully before printing

• Make sure the first layer is accurately calibrated

• Use a smooth sheet for a smooth dial surface

• Use a textured sheet only if a textured clock face is desired

Important 3MF instructions

Open the supplied file as a complete PrusaSlicer project:

File → Open Project

Do not import the 3MF as geometry only. Importing it only as geometry may discard the virtual extruder assignments, wipe tower, filament settings, and manual tool-change configuration.

The project uses four virtual extruders:

• T0 — White

• T1 — Black

• T2 — Red

• T3 — Green

Start the print with white filament loaded.

Manual filament-change sequence

Follow the printer prompts in this order:

1. Black

2. Red

3. Green

4. White

5. Black

6. Red

7. White or the desired body color

Complete sequence:

Start with White → Black → Red → Green → White → Black → Red → White/Body color

During the final change, the project requests T0/White, but the visible dial artwork is already complete. The remaining portion forms the clock body.

You can therefore use another filament with the same material type and similar printing characteristics. The prototype shown in the photos uses gray PETG for the final body section.

For reliable results, all colors should use compatible material, temperature, and flow settings. Avoid mixing materials such as PLA and PETG in the same print.

Important slicer settings

The supplied project includes:

• Four virtual extruders

• Manual filament changes using M600

• Wipe tower enabled

• Correct color assignments for all model parts

• Number of cooling moves set to 0 for all four filaments

When replacing the included filament profiles, verify:

Filament Settings → Advanced → Number of cooling moves = 0

This is important for manual filament changes. MMU-style cooling moves can produce excessive extrusion and create a large blob on the wipe tower.

Keep the wipe tower enabled. It restores stable extrusion and removes remnants of the previous color after each manual filament change.

Printers that do not support M600 require an equivalent filament-change or pause command appropriate for their firmware.

Assembly

1. Insert the quartz movement into the recessed holder from the rear of the clock.

2. Align the shaft with the center opening.

3. Push the movement into the holder until the retaining clips engage.

4. Confirm that the movement sits flat and securely in the holder.

5. Set the movement to exactly 12:00 using the adjustment wheel on the rear.

6. Install the hour hand pointing at 12.

7. Install the minute hand pointing at 12.

8. Install the second hand, if used.

9. Check that the hands are parallel and do not touch each other or the clock face.

10. Insert one AA battery and observe the hands through a full rotation to confirm that they move freely.

11. Hang the clock using the integrated rear keyhole slot and a suitable wall screw.

Do not force the clock movement or hands. Compatibility and hand-installation order may vary slightly between movement manufacturers.

Remixes

Remixes are welcome under the CC BY-NC-SA 4.0 license.
Please keep the original Maxπ logo visible whenever reasonably possible. If your modification requires changing or removing it, please retain clear attribution to MaxPi and link to the original model.

Support/thanks

If this helped you, you can buy me a coffee:
https://ko-fi.com/maxpi

Or use my referral @MaxPi when purchasing a Prusa printer — you will get Prusameters and a free spool of filament, and so will I 🙂