Saturday, May 21, 2005

Care of the chiming mechanism in our steeple clock

NCI is proud to announce the newest member of it's AMERICAN COLLECTION. We have had several requests for a large mantel clock at a good price and have commissioned STERNREITER to build us the NEW HAVEN STEEPLE CLOCK.

Due to the vast majority of new clocks sold with Westminster chime verses time-and-strike we knew we had to go with a Westminster chiming movement. As you know most manufacturers don’t even bother with time-and-strike anymore unless cabinet space doesn’t allow for Westminster.

So, in order to have a chiming movement we had to use the smallest mechanism possible. In the interest of space we used short chime rods instead of the large, deep-sounding rods used in our Bauhaus model.

In order to get the biggest sound possible out of these little rods I had to use my knowledge of acoustics.

There is no access door in the back of the clock for this very reason. A small door with wing-nut latches is handy for adjustments to the movement, but it seriously deadens the sound. Whenever you have a backboard on a clock which isn’t one solid piece it will not resonate like a drum. Instead we used one thick piece of solid wood which is able to vibrate the entire length of the clock.

I did consider using the wing-nut latches for the entire one-piece backboard. We tried making a few to test this approach. The trouble was that when the backboard wasn’t firmly attached to the body of the clock vibrations were loose and not as resonant. When the backboard is firmly attached to the body with several screws it allows the entire clock to act as a resonating chamber. Just as the body of any string instrument is firmly attached to the fretboard to allow the vibrations of the string to resonate fully.

To adjust the hammers it is possible to remove the dial after taking off the hands. Another option would be to VERY SLIGHTLY move the rods themselves. To do this you can just reach in without any disassembly to the clock. I’ve noticed that sometimes the chimes get slightly out of adjustment just by taking the packing material out of the rods. That can be fixed simply by moving the rods one way or the other with just your index finger (no bending required).

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