Sessions Mission style clock – an interesting challenge to what should have been a routine servicing

This is the only mission-style clock in my collection. Made by the Sessions Clock Co. of America in or about the 1920s it reflects classic Mission design and is rather attractive. I was not searching for this clock but a $10 find in a Pembroke, Ontario thrift shop is hard to pass up.

Though this clock is a non-running Sessions movement they are simple enough to work on. The time side was easy to get running with a simple crutch adjustment but there was a good reason the strike side had not been working in many years. After servicing the movement I now understand why it ended up in a thrift shop.

Mission-style clock by Sessions

The case is in reasonably good condition requiring a light cleaning and there is nothing missing overall save the winding key which can be easily sourced. The minute hand fell apart while I was setting the time, probably as a result of being bent so many times but it can be easily repaired.

The movement is a conventional Sessions design with a between-the-plates escapement setup as opposed to earlier Sessions movements that had outboard escapements. The movement is complete and everything is there including a few extra parts thrown in for “good” measure.

Movement issues

I observed a number of “X” marks around bushings but absent are punch marks or replacement bushings. Was there a plan to install new bushings?

An X mark beside a bushing hole and why the mysterious drilled hole adjacent to the escape wheel bushing hole

An “X” mark usually indicates a bushing hole that requires remediation, and why is the mysterious hole perilously close to the escape wheel bushing hole?

The cam wheel pegs for the strike lever have both been soldered and although it is not the neatest work the repair seems solid.

Soldered cam wheel pegs

The actuator arm for the hour strike had been bent so many times that it snapped off when I tried to test the clock before disassembly. This can also be repaired.

The real fun begins

I make it a point to label the mainsprings so that the time and the strike mainspring return to the same location. At times it makes little difference but, at other times, as in the case of this movement, the difference is significant.

In this movement, there is a slight difference in the strike mainspring arbour design so that the arbours cannot be reversed. Because of the slight variation in the strike side mainspring arbour the gears do not mesh correctly if the arbour is reversed. A past repairer switched the two mainspring arbours, time to strike side and strike to time side, and bent wheels to make them fit.

The count wheel is shaped into a bowl to force it to engage the second wheel arbour

Because the mainspring arbours were switched, a previous repairer had screwed a small brass piece into the plate to push the arbour to the right and enable the second wheel to engage the count wheel.

Brass “fix”
A brass piece (left) was screwed into the plate to push the second wheel toward the count wheel

A piece soldered onto the arbour to prevent lateral movement was unnecessary because the abours had been switched.

Brass piece soldered onto the time side mainspring (below hammer) to prevent the arbour from moving too much

It took a couple of assembling and disassembling tries to discover the problem, which is valuable time wasted on the bench.

In short, a past repairer did not understand what they were doing and made unnecessary changes complicating what would otherwise be a routine service. Home-cooked repairs are at times functional but often they are an absolute disaster and sometimes the most challenging part of clock repair is fixing other people’s shoddy repairs.

The remainder of servicing went as expected. There was some movement of the pivots in the pivot holes but not enough to justify bushing work at this time. As expected there is less wear on the strike side.

Minute hand fixed, hands, bob, and numerals polished and now on display

So, another clock was brought back to life and a satisfactory repair despite the challenges.


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