Jerome & Co. mantel clock – many issues, it wants to run but not today

Jerome and Seth Thomas round top clocks side by side
Jerome (left) and Seth Thomas (right) round top clocks side by side

How you ever wondered what keeps mechanical clocks going? It’s a miracle they work at all when they are so worn as this one.

Most old clocks I come across have common issues, dirty, oily movements such as worn pivot holes here and there. Generally all they need is a good cleaning to put right.

Vendors mart at the NAWCC convention, June 2019

I bought this  Jerome & Co. time and strike mantel clock in Springfield Mass. during the annual convention of the National Association of Watch and Clock Collectors in June 2019 and I have only just got around to having a good look at it. It was purchased as part of a small package deal with other mantel clocks. All the clocks had very good cases but movement maintenance was largely ignored by the previous owner.

While the Jerome & Co mantel clock case was in exceptional condition, the movement was in pretty bad shape. No amount of encouraging would make it run.

In terms of style it is referred to as a round top, from the mid to late 1870s

Chauncey Jerome along with his brother Noble introduced the first mass-produced brass movement in 1839 two years after the depression of 1837 knocked out 90% of factories in the Northeast (New England States). The 30-hour brass movement was rugged, cheap to repair and not subject to swelling found in wood movement clocks. Despite business ups and downs Chauncey able was able to maintain a viable clock business until 1868 but later died penniless. This 8-day clock was made well after Chauncey’s death under the New Haven banner.

The Case

In terms of style it is referred to as a round top, from the mid to late 1870s. The case has been well cared for and while there are a few nicks and scratches consistent with age there are no missing Rosewood veneer pieces. However, there is a small age crack at the 11 o’clock position.

The door, which includes the mirrored tablet opens to reveal the dial mounted on a dial board. To access the movement the dial board must be removed; 3 screws secure it in place. I have seen Jerome clocks with dial boards that are in very poor condition and am not surprised that the dial mounting board is a replacement. The dial is paper over zinc with an inner brass ring and an outer brass bezel, and appears to be an early replacement.

There are two labels. One behind the mirrored tablet and the other on the backboard. The inner paper label occupies most of the bottom half of the backboard but there is an over-pasted label in poor condition. I can only make out “J.J.”, “Clockmaker” , “86 Court St” and “formerly Haymarket Sq”. It appears to be J.J. Beals who was at Haymarket Sq. between 1849-61 and then moved to Court St. I do not know how long he operated his business at the Court St. location.

Time and strike movement, dial removed

The Movement

From the general condition of the movement this clock has been on the bench several times during its hard life. Helper springs are usually made of brass, these are made of steel wire and not original to the movement.

I put the clock in beat and while it sounded healthy for a minute or so, it abruptly stops. The strike side, on the other hand, runs reasonably well.

I took the movement out of its case, inspected it carefully. It was very dirty, over-oiled and there is bad pivot wear in several locations. Several bushings are required. The worst pivot wear is T3 back plate, escape wheel front and back and S3 front plate. All the pivots look good and the lantern pinions seem to have minimal wear.

One of the worst pivot holes, S3, strike side

Now to disassembly. On the strike side aside from the pivot wear the stop pin on the warning wheel is quite worn. I must consider whether to replace or repair it. The pin may last for many years and if it did fail the strike train would simply run down.

Worn stop pin on the warning wheel

On the time side, aside from the enlarged pivot holes I discovered a bent second wheel which is enough to stop the clock. This accounts for the newer time-side mainspring. This would not have been discovered had the movement not been taken apart.

Bent second wheel, time side

I put the wheel in the 3-jaw chuck of my Taig mini lathe, gave it a few spins to determine how much I had to straighten it, selected a punch from my stake set and  inserted the pivot in the hole end of the punch and gently straightened the arbour. The steel is relatively soft and bends easily. When the mainspring broke the second wheel evidently took the brunt of the force. Why the bent second wheel was not noticed during the last repair is a puzzle.

So, lots of problems, none of which are insurmountable.

The parts were placed in the ultrasonic, cleaned, rinsed, dried and laid out for further inspection. There are no other bent arbours and the gear teeth look good. The pivots were polished prior to the bushing phase.

A bushing about to be pushed into place (Bergeon bushing machine)

I installed nine bushings; S2 & S3 front plate, minute wheel front plate, T2, T3 and T4 front plate, T4 and escape wheel, front and back plate. A final pegging of the pivot holes and now it is on to reassembly and testing.

I put the movement together with relative ease but I have two issues. One, the strike side mainspring refuses to hook correctly on its arbour and two I am getting an erratic beat. It drifts in and out of beat, and stops after about 5 minutes. I am close but there is more work to be done.

As I continue to make more adjustments, experiment with bob weight size, adjust the verge angle and so on I will report my findings in the next post.

It will run reliably, I guarantee it!


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