The Grand ‘Grandchildren’s’ clock

Design Concept: -

Starting out with no idea of the design, this clock mechanism is built on purely trial and error and wild imagination. (I am no engineer – this is a piece of art more than a mechanical clock and work of design.) I decided to take part in the Timepiece contest and this being my first ever contest having no idea what I was doing, or what to expect.

In all of 5 minutes, I decided to build a clock from scratch with no remixes or borrowed ideas – using gears and a novel way to drive it. The clock would go by name “The Grand – Grandchildren Clock”. This set me off with a blank screen and basic shapes and parts which are available on Tinkercad. The result this unique self-designed model with zero AI content. Printed and deigned in evenings and over weekends (Thank you Tinkercad – and the Autodesk team 100% designed using opensource online cad program.)

This model ideally needs the Creality K2 - bed size and multi-colour printing, painting, additionally consideration to working tolerances. (I only learnt about Support Painting in the Creality print at the end of the build.)

Wanted it to be educational for my Grandchildren, turned out it was quite educational for Granpa!

Ideally leter needs to include a toy or some interesting addition for them as motivation (Im thinking a Marble Rollercoaster and lift which is in design now.) This should help teach them how to read old analogue time displays and how gears work.

The work on the Stepper drive, Marble Roller Coaster and Marble pump / lift will be added and also be free to down load.

At the time of preparing this for submission – the actual Clock Meachanism is designed, printed and assembled including functional tests completed as successful.

Please note the design needs lots of hardware. I used items I already had available in my 3D work area and garage.

Clock ratios where to be 60:1and again 60:1. If the Stepper motor works the Clock must keep time and be potentially functional. The design as a concept teaching tool and for the sheer love I have for my Grandchildren. I needed to be enjoyable. Yet, challenging me to the next level of 3D printing.

(The drive to be added and shared later on should allow for stepper motor set at 60 RPM – to activate the radial Arm and marble lift.

If fully working this design can open a whole host of newer designs and themes for the basic design.

This clock is housed in a Safety Glass display which is supported by 3D printed frame Top and bottom. (This will be shared free as soon as I can sort out the file issue I am currently having.)

Size – The completed cock assembly with base is close to 700mm high by 230mm x 300mm. The glass case takes it to just over 770mm tall. (Large and striking with light effect from the power supply box below.)

How many printed files?

Total prints at time of loading for contest – approximately 52 – Some items are to be added before the contest dead Line so this figure is indicative only. Note some items are printed in 2 and multiples.

Printing settings

Filament - Creality CR-PETG Transparent (I guess I used 10kg) and Generic Glow in the Dark Blue only for the clock-face numbers.

Print time – Print time and my rudimentary experiments was in excess of 130 hours minimum.

(You can reduce time and save on filament by reducing infill in some cases wall loops – It is over engineered rather than not have noting to show for the contest.)

Printers used - Creality K2 x 2

Files uploaded are actual printed parts (I eventually loaded Generic files as I cannot seem to get the Plate files loaded no matter what I try to do.

Please note in some cases the support structures and orientation are critical – I learnt the hard way. Especially on Bevel gears.

(There may be errors on file loading – so if you need help – please feel free to contact me for support.

It is possible smaller printers yet, originally made on the Creality K2 – Willing to help anyone wanting to build one of these for themselves – even on a smaller printer. Would need a few extra files for joined parts.)

In some cases, there is quite a bit of finishing work required – (An Example is the Radial arm Ladder – it needs to be press fit – otherwise it is wobbly and does not work – (Needed to print three of them to eventually fix the problem.)

You may need to utilise Expert mode and specifically check the Z-Axis offset for larger flat placed parts. Bed must be clean – and prepared for adhesion. (ABS Slush or Glue stick)

I will be developing an PDF instruction step by step for assembly - this way I will also be able to check that the moodel is 100% complete.

Temperatures used for CR-PETG was between 240 and 247 degrees.

Nozzle - 0.4 mm nozzle Layer height 0.2mm – Standard

Note the second picture is with the correct drive train you can see the 4 Gears that feed the hours to the hour hand - which is the last gear.

Added files for plain Clock hands – as mine were customised to have my Grand children’s names on each of them.

Most crucial part of the clock is the bevel gears and specifically the Bevel gears that feed and take power between the two levels. (It is important to slice these at very least with teeth in up position and not have support and interference on them while printing. – here I had to reprint them to ensure a better product result.)

The only items I need to really improve is the Hour drivetrain.

K2 printers are capable and much fun. (Will be ordering 0.2mm nozzles soon want to do more intricate work.)

Assembly: -

Various hardware, screws, nuts, bolts, washers, belts, etc., are required for this model. (Take note – I have a selection of bolts and nuts and used items and fitted as required. – (A BOM - Bill of Materials may be added later to help others build the same. – I will not have enough time to do this now and met the contest deadline – so I commit to further updates and sharing of information in future.)

Two Aluminum 4mm rods about 330 mm long trimmed to length when assembly is completed.

Super Glue

As for screws, nuts, and self-tapping screws I used what was on hand – (M2 to M8 in various Lengths.)

Some holes need to be reamed and or polished with fine grit paper.

Future developments.

For the Stepper Drive and Toy - ongoing and to be released added after the contest.

Tools

If available a Dremel (Mico-grinder) or similar devise would be advantageous. Drill 2mm.

Allen keys, Pliers, Screw drivers - basics.

Parts Should be prepared for Painting and Painted before assembly. Or printed in colours.

Drills 1.8 - 4mm would be advantageous. I used a 2mm only and then the Dremel.

Additionally required as follows: -

Bearings 608 (OD 22mm x ID 8mm x Thickness 7mm) (I bought 30 off and had some spare at the end)

Bearings Inner dia x 12 Outer dia 32 by 10mm thick I used 4 of them one on each hour hub and the radial ladder.

2 x 4mm Aluminium rod – Re-cycled an old, discarded TV Antenna for the two shafts. This will need to be drilled with 3 places x 2mm holes at input side of radial Clock radial ladder and seconds arm if required as well as bottom shaft at end of the gear train and on the Hour output Pully.)

1 x Stepper motor NEMA-17

1 x Pulse drive Stepper motor MKS – PWM Signal generator (DC 12V 24V MKS OSC Stepper Motor Pulse Signal Generator Module)

1 x Power supply

1x Main Stepper driver. (The MKS is to send signals and to prtect it from overload an nroamla Stepper driver recieved the pullse and does the hard current work.

My current milestone reached for this contest is to have a fully a functional Clock mechanism designed from scratch - printed and tested.

Made, designed and built by ‘Cephas not of Rome’

The Grand 'Grandchildren's clock'

0.2mm layer, 2 walls, 15% infill