Mission Clock by Clayton Boyer
The appeal of this design is to construct a clock all of hardwood as was the technique of 150 years ago. Clocks made in this way have run successfully for at least 150 years. The design is a Clayton Boyer one.
I’m afraid as the construction progressed I have strayed from the real simplicity and austere design.
The raw wood is maple 3/4 inch by 2 and 1/2.
The boards were ripped in half to get a little thicker than 5/16”.
These boards were then thicknessed to 5/16.
All the wheels are octagonal dividing a circle into 16 angles of 22.5 º each.
I checked my miter for square and adjusted the zero before setting to 22 1/2º
With all the wheels made from octagons the only measurement needed was the longest side and a constant angle on the miter.
Clayton suggest laying up the wheel on aluminum foil so that things won’t stick - great suggestion and works well.
The pieces are not clamped but rather the joints are glued and then they are taped. The plans suggest masking tape but I used clear packing tape so I could examine the joints.
I found that if I dry taped the wood on one side then flipped it to open the joints I could get tighter joints.
A little weight was added to try and ensure that they were “flat”.
As I glued these together I turned to model airplane builders crazy glue with an accelerator which works well - hope its strong enough.
The 7 octagons and one hexagon have been assembled. I glued all except the last trapezoid in place and then custom fit the last one to give tight joints throughout.
1/8” half lap joints are made for the spokes. Seven of these are required.
Clayton suggested laying the “spokes” over the glued wheel and cutting both to make an inlay. It didn’t work well for me and I was unhappy with the fit.
I wanted to make a “fancy” spoke to wheel connection, so I took a fleur de lis design and made a spoke set the same overall dimensions as Clayton’s plan
Since the spokes are really inlays - in my case I cut trial pieces for both the male spokes and the female wheel to test my design. With the spokes 0.010” under size I got a nice fit.
The female cut has to be lined up with respect to the octagon but not all that accurately since all “edges” get cut to final design.
The blank is temporarily glued to a sacrificial piece allowing alignment and full through cuts.
I stained and pre-finished the spokes so that the contrast would show off the inlay.
A test fit shows that the spokes fit into the wheel easily with 0.010” . The blank remains on the CNC table so that the teeth will be centred with the spokes and the center accutately found.
The inner curves of the wheel are made by “eye” and I didn’t leave quite enough wood where the spokes intersect the wheel and an adjustment has been made.
This is a 48 tooth design and I have opted for Cycloidal tooth form since this is a very traditional clock. The center of the spokes is the alignment spot.
This test piece is made of plywood and it gives a good Idea of what I’m trying to do.
The full set of wheels was done on this same design and scaled to match the wheel size.
For those who hate removing the contact cement from the back of the wood I completely covered the wood with clear packing tape and then sprayed contact cement to that - cleans easy! Remove the tape and the contact cement is gone as well!
The 19 tooth face gear is a little over 2 “ in diameter and is the foremost gear and so is most visible.
In keeping with the theme I carved four dime sized fleur de lis on the face of the gear.
The detail achievable with the 24” CNC by Widgetmaster is really impressive.
Arbour buttons were cut leaving little tabs - there are 5 - 3/4” buttons and 3 - 3/8” buttons. All have a Fleur on the face.
The Arbour buttons up close
The “wings” at the front and rear of the clock are being dressed with 2” by 4” by .35” Fleur de Lis.
This is the “rough cut” with a 1/8” end mill and 60% passes
The rough cut leaves obvious ridges between cuts but causes no problems for the 0.062 ball mill.
The finished product has really good definition. A finger nail can still detect ridges but they are not visible to the eye.
Clayton left the center of the supporting shelf as a place to put something. This is my choice.
The “wings” for the front and back plates are very visible and provided an opportunity for more “fleurs”. Overkill? Probably!
These are the plates with the wings and plates shown - the top and bottom bracing and spaces are yet to be cut.
The pendulum hanger that is positioned on the back of the clock - sports a small fleur design.
The wings have been sealed and the “fleurs” glazed with a dark brown finish so they show better.
The pendulum bob has a 5” fleur carved on the face of the pendulum bob.
This “fleur” is about 5 in across and will be used to face the pendulum bob.
The bob will be round and weighted on the backside.
The shelf bracket supports have a partial outline of a fleur
The top of the shelf back will mount to the wall and shows the same carved feature
The top back of the shelf
The center plaque shows the name of the clock the designer’s name Clayton Boyer and finally my name as builder
As shown earlier - The side supports have half profiles of fleurs
The plates are ready for glue up with the 1/4” plates, 3/4” wings and 3/4” spreaders all in place.
The pendulum rod is made from “scrap” pieces of maple 1/4” by 3/4” joined with a “puzzle” piece connector and glued permanently.
The comleted42” pendulum will be plenty to make a one second pendulum.
5” Fleurs were used as cheek plates on the turning sheave.
With all the wheels and arbors installed I discovered an anomaly in the plans and needed Claytons input to sort it out - he did.
The finished unit sporting all her Fleurs.
“Mission” now on her shelf on the wall only wants attention every 3 days or so for a rewind.