I asked my daughter if she would like me to build her a clock and she said she would rather have a calendar. The calendar that she wanted was a Mayan calendar that showed the day of the cycle and the glyph that went with that day.
The Mayan calendar has 13 days in the cycle and 20 glyphs that correspond to those day cycles. since they interrelate it means that there are 260 days in the complete cycle.
This clocks provides a “dial” that keeps track of what day and what glyph go with the day. The time train is a 24 hour one and moves the calendar one space forward each day.
The running train is directly from Clayton Boyer’s Swoopy - a “grasshopper escapement available from
The Myan Calendar can be represented by two concentric rings of characters.
The inside ring has the 13 days in the Myan cycle and the outer circle are glyphs of the dieties and there are 20 of those. By turning the inner gear one tooth per day - a full 260 day cycle will be achieved.
I use a scrap piece of 1/8” steel rod to align the pinion space and gear.
I apply glue while it is still on the scrap 1/8” rod and by turning on the drill I can easily get the components together, glue spread and aligned.
Now just clamp and wait. On this set I have used a piece of cherry wood for the spacer because on previous clocks I have had the spacer separate on the plys if I use plywood where there is high torque.
Gluing the frame. I drill the arbor holes before this gluing stage so that they are all properly aligned. The central spacer block in the glue up is to ensure that the arbor alignment stays and the frame stays square.
For the curved pendulum I laminated 3 - 1/8” pieces of mahogany into a curve. I didn’t carefully lay out the curve but simply clamped in what looked OK.
After the clamps were removed and fed a couple of times through the thicknesser - the “blank” is ready for fitting
The basic running gear runs really smoothly and purrs quietly under 8 oz. of weight
The escape mechanism is assembled on the bench
Since the unit is “Mayan” the pendulum has been made to keep with the theme.
The running gear is working fine - next is to work the calendar train.
The “Time Train” is the calendar train and is made to move the calendar one “space” each day and to make the change between 12PM and 2 AM
In order to work the calendar the “pinion” on the left replaces the minute wheel and has one leaf or pin and activates the center gear which has 24 teeth and so rotates once per day.
The last gear in the train has 13 teeth to match the Mayan calender and attaches directly to inside wheel of the calendar.
The time train centers were left exactly as Clayton Boyer had designed it and the calendar gears were designed around the arbor centers.
The Calendar Train is fully mounted and ready to go.
The day count in the center has brass markers. This has made it too heavy for my liking and will be changed for a lighter design using nylon perhaps.
The “Glyph” wheel will also be removed as my daughter wished to hand paint the glyphs - that can wait and be done at her leisure.
One last piece was to instal a reversing set of gears - yes - I had it going backwards!
Embarrassing or what!!