Case

Locus Pocus Clock Design Showing Casing - Front and Back Panels Joined by Clockwork Frame

Once the Locus Pocus clockwork mechanism was finalized, I considered how to design the Locus Pocus embodiment and casing. Several primary design elements were needed:

Support of clockwork mechanism
Provide for a clock face to go with the mechanism
Allowance for spindle mechanism to protrude beyond the face - to allow for clock hand motion
Provide an interesting design for a clock look and feel
Provide flexibility for refinement & customization

Research

In considering potential clock case designs, I reviewed the casings used in some of the previous related projects.

Project	Casing
Modern Weasley Clock	Laser Cut Clock Face
Weasley Clock	Pre-existing Full Grandmother Clock
Where'sLy Clock Project	MDF frame for hardboard clock face
Magic-Clock	Pre-existing wall-clock body with custom laser cut clock face

I also spent quite a while looking at examples of grandfather clocks - more specifically moving to image section of the search.

Case Design for Locus Pocus

I chose to create a new case design, rather than search for an existing clock body for retrofit. I decided on an open-case approach to combine flexibility for customization with an interesting look and feel, while meeting the mechanism constraints.

It occurred to me that an simple and elegant design could use the clockwork frame directly as part of an open casing. The clockwork frame would serve as the central part of the body. This would be used to couple front-facing and back-facing wood supports. The front-facing support would have a simplified grandfather clock shape (with etched pendulum), and the back-facing support would have a rounded top - to help highlight the front-facing accents. The overall design was a sort of mid-century modern variation on clock casing.

Front and Back Panel Case Design

I used Autodesk Fusion to create the front and back panels for the case. I used the existing Fusion design for the clockwork frame to project the dimensions of the frame supports.

Front Panel Design

I designed the front panel to incorporate:

Hole for the clockwork spindle - offset from projected clockwork frame design
Holes for the clockwork frame supports - from projected clockwork frame design
Clock face of 10 inches - construction dimension (not directly cut for case) - surrounding the spindle hole
Just enough width to frame the clock face on both sides
Enough height to provide a sense of a mini-grandfather clock
Top embellishments inspired by online images many different grandfather clock designs
Drawn body design representative of grandfather clock interiors, with a pit-and-pendulum style pendulum

Locus Pocus Clock Case Design - Front Panel

Back Panel Design

The back panel needed to mirror the front panel for structural support, but did not need to incorporate aesthetic design elements, since it would generally not be in view. I considered using the same outline with top embellishments as the front panel. In order to highlight the front embellishments, however, I used a basic curve at a lower point than the front embellishments.

Locus Pocus Clock Case Design - Back Panel

Laser Cutting Case Design

To create the front and back panels, I laser cut them using 1/8 inch Baltic Birch Plywood. I exported the Autoodesk fusion sketches in DXF format and used Adobe Illustrator to send the designs to the Epilog Helix laser cutter in the lab.

Prototypes in Cardboard

Before cutting the full panels for the clock design, I created prototypes in cardboard. I first created a prototype of the clockwork frame connection, in order to ensure a fit. For this, I removed the outer lines of the panel design and substituted a straightfoward square.

Locus Pocus Clock Case Design - Test Fit for Clockwork Frame Connection

The fit for the frame was exact, which was not surprising, since this was based directly on the clockwork frame design elements. It also helped with a design revision - the clearance around the spindle hole was present, but seemed like it should be larger. I adjusted the diameter to give additional clearance.

I went on to do a cardboard prototype of the full front panel. The fit for this was also exact.

Locus Pocus Clock Case Design - Cardboard Prototype for Front Panel

Laser Cutting Front and Back Panels in Wood

With successful prototypes in cardboard, I proceeded to laser cut the actual case panels in 1/8 inch Baltic Birch Plywood. I ran into an issue with the wood cut version. The cardboard sheets for prototyping were larger than the available wood stock, and the wood sheets were not quite wide enough - just by a whisker. I made a straightforward width dimension adjustment in the Fusion design. Since this did not impact the clockwork frame connection, I proceeded with cutting the adjusted panel designs in wood. I used the lab settings for the material, but it seemed like some places had not cut completely through, so I ran a second pass on the cuts.

Locus Pocus Case Design - Laser Cutting Front Panel

Locus Pocus Case Design - Laser Cutting Back Panel

The final cut panels fit perfectly and made things really start looking like a clock.