I have written about this clock several times in the past 10 months but I am making good progress which I will detail in this article.
This is how it arrived at my house last spring, dull and lifeless but with good bones and most everything original.
First, some background information about the clock.
This federal-style banjo clock was made in the 1840s perhaps as early as 1840. I am reasonably certain it was made by John Sawin of Boston, by either himself or one of his apprentices or associates.
The movement and case construction bears a strong resemblance to a Willard timepiece and there is a good reason for this as John Sawin apprenticed under Simon Willard and was a journeyman under Aaron Willard, famous clockmakers of the day and makers of the original patent timepiece.
Unfortunately, there are no identifying markings on the movement or the case but key indicators such as the placement of the movement mounting “ears” and the design of the door and bezel catches tell me that there is a very strong connection to John Sawin, enough to say that he is the clockmaker.
I have completed repairs on the case aside from the wood bezel mentioned later in this post. The repairs include new veneer pieces, harvested from an old mahogany ogee clock, a new post for the acorn finial, and two applications of traditionally prepared shellac.
The movement has been cleaned, serviced and wear issues addressed.
The glass dial was broken and new flat glass was ordered and installed. The old weight cable was replaced.
The dial, with some stains and discoloring, will be left as-is.
Three issues that have slowed me down
The three issues are a weight cable that is too short, a twisted suspension spring, and a cracked wood bezel.
Weight cable that is too short: The clock stops when the weight is three inches from the bottom of the case and runs six days instead of the usual eight. I have run the clock several times and the clock consistently stops on the 6th day. I believe that the brass cable was frayed from wear and a previous owner shortened the cable rather than buy a new one. I have various sizes of cable and have chosen a slightly thicker brass cable with a nylon core. The nylon core prevents the cable from snarling and coiling plus the more robust cable is more than enough to carry the heavy iron weight.
However, a thicker cable results in a double layer. The cord will wind down from the top layer and the diameter of the drum has been increased due to the first layer. This means that with each turn more length of the cord will be removed from the top layer. Thus, the weight will reach the bottom of the case sooner than intended, reducing the runtime. A thicker cord makes it even worse. I believe I have struck the correct balance between thickness and length as the clock now runs its full 8-day cycle. Had the cable been any thicker the runtime would increase.
Since it had to be taken apart to install the new cable I cleaned the pivots, pegged out the pivot holes, and re-oiled the movement. Problem solved.
Twisted suspension spring: The keystone is the piece between the suspension spring and the pendulum leader. It very nearly hits the large wheel of the motion works on the left side as a result of a twist in the suspension spring. A bent spring is a consequence of leaving the pendulum assembly on the movement during transport.
A weight driven banjo clock must be partially disassembled when transporting and damage could result if the steps are ignored.
Unfortunately, I cannot source the suspension spring as a separate item and must purchase either the keystone and suspension spring together from an American supplier or the entire spring, leader, and stake for about $55.00 from a Canadian supplier. It does not make much sense but in the meantime, I have managed to straighten the suspension spring and it is functioning better than it was. Problem partially solved.
Cracked wood bezel: The crack is just above the number eleven on the dial. It was cracked initially and I used hide glue to close the gap. I now realize that hot hide glue I am using has a low bonding strength because it separated after a few weeks (a dry house in the winter does not help).
I have ordered a band clamp designed for furniture repair and will use stronger glue. However, I run the risk of the bezel splitting again and perhaps not in the same place. Another option is to fill it and simply live with a slightly larger bezel that may not fit the dial catch exactly. Problem not solved, yet.
There are three iron pin hooks that hold the dial in place. The hooks are twisted inward to secure the dial.
In the meantime, it is keeping perfect time.
I am in no hurry for this clock. It is worth moving slowly with the repairs and ensuring that everything is completed correctly.