Antique and Vintage Mechanical Clocks

My collection of wall clocks includes several schoolhouse models and I am continually impressed by their resilience despite their age.

While many of these clocks spent their lives in school rooms, some ended up in commercial establishments and offices, often neglected until they stopped working. I’ve seen clocks with bushing holes so enlarged it’s a miracle they still ran at all.

This particular clock, manufactured by New Haven, boasts a classic design with a twelve-inch Roman Numeral dial and a distinctive short drop style.

The softwood case is veneered in Rosewood veneer accents. The clock’s case must have been quite elegant at one time, but now it is showing much wear and tear.

Given the condition of the case, I anticipated that the movement would be just as well-worn.

Let me point out that the servicing is being done under less-than-ideal conditions. I am at our summer cottage with only the basic tools for clock repair, so I must either improvise or skip certain procedures.

Removing the movement

After removing the hour and minute hands, you will find that three screws hold the dial in place. Once these screws are removed, the next step is to take out two movement blocks that secure the movement. This is done by unscrewing the blocks (each held by two wood screws) and then pulling out the movement. Once out the blocks can be removed.

Disassembly and inspection

The first step is to contain the power of the mainspring. Since I did not have access to my standard equipment, I had to improvise. I would normally use a C-clamp to restrain the mainspring, but with none available, I used a stiff piece of copper wire and wrapped it around the mainspring. Not ideal but it works.

The movement is in surprisingly good condition.

Once the wheels are out it is time to visually inspect the components including the gear teeth, pivots, escape wheel pallets, the condition of the manispring, and lantern pinions.

Before placing the parts into the ultrasonic cleaner, I clean the pivot holes with toothpicks and wipe off any excess dirt and oil. Since I plan to reuse the ultrasonic cleaner several times, putting excessively dirty parts into the cleaning solution can shorten its lifespan.

Opinions vary on whether mainsprings should be cleaned in an ultrasonic cleaner. I believe it’s a matter of judgment. If I am not planning to reuse the cleaning solution (mainspring oil can render the solution unusable) and can thoroughly dry the springs, I have had good results by placing them in the ultrasonic cleaner.

In this situation, I have opted not to clean the mainspring in a solution.

Next is the reassembly of the movement leaving out the main wheel and mainspring. Without tension on the wheels, this is a simple way of determining wear.

Wheels that move laterally suggest enlarged pivot holes. Lateral movement affects the meshing of the gears and with enough wear the gears do not mesh properly and the clock will stop.

In this movement, the third-wheel front plate shows the most wear. However, it is not worn enough to require a new bushing at this time. If I were in the clock repair business and this was a customer’s clock, I would definitely address the need for a new bushing. This is compounded by the fact that I do not have bushing tools with me.

The pivots exhibit no significant wear, as confirmed by the fingernail test, which revealed no ridges. If you feel any ridges, grooves, or irregularities, it indicates wear on the pivot. A smooth pivot suggests minimal or no wear. Although I had to use a portable power drill for cleaning/polishing, the cleaning process was satisfactory despite it not being the ideal method.

My main challenge is the mainspring. I’m currently working with minimal tools and would like to service the mainspring, but I don’t have a spring winder.

I am determined to service the mainspring and will find a solution within the next day or so, reporting on the procedures as I go. In the meantime, this is as far as I can proceed with this movement.