Expert: Martin Meyer - 6/8/2007

Question
QUESTION: I have a Tempus Fugit mantle clock that a friend asked me to look at....I'm a bit of a "fixit" guy. Anyway, the clock had been wound so tight that it would no longer run.  I took the mechanism out of the clock and backed off the springs and it now runs very well, however, it's running really fast.  I can't see where it is possible to regulate it, so I was wondering if there were a secret?  It's a nice clock....says it was made in Germany... fairly old... it had been wound that tight for about 20 years????maybe...not sure on that.  Will it perhaps level out after it's run a while?

ANSWER: Hi Cecil,
I would need a little more information to answer your question properly, but I'll give it a try. Does this clock have a pendulum? If not, what does the movement look like from the back? Does it have a flat wheel suspended on a VERTICAL COIL about 1" long that rotates back and forth? Does it have a flat wheel with a FLAT coil spring on top of it? Most important, how many minutes does it gain in 24 hours? If your clock is gaining more than 1/2 to 1 hours per day, your problem is not a regulation matter, and I will need the additional information to help you.
  If the clock has a pendulum, the regulating mechanism MUST be on the pendulum, either an adjusting nut on the bottom, or a method of raising and lowering the pendulum suspension spring at the top. If it doesn't have a pendulum, it may be a "floating balance" (has the vertical-coil-suspended wheel) or "balance wheel" (has the flat coil spring above the wheel) movement. The balance wheel mechanism usually has + and - symbols and a screw or pointer somewhere; you just move the screw or pointer a small amount in the proper direction. It may be at the very top of the movement and hard to see, so look closely. The floating balance movement has a very delicate regulating mechanism, consisting of three prongs on top of the wheel, extending out radially from the center of the wheel and pressing on the wheel at their tips. You move this prong affair to the left or right on the wheel to regulate the timekeeping. Be careful! You do not want to twist or push on the wheel itself or you will break the clock. I hope this information is helpful. Remember that if your clock is gaining hours a day, this is NOT a regulating problem, and get back to me with the additional information, and I will try to help. Thanks for your question.  Martin

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QUESTION: Thank you for your quick reply.  The clock does not have a pendulum, however from the back there is a flat wheel suspended on a vertical coil that rotates back and forth as the clock runs.  As accurately as I can figure it gains about 3 hours in 24 hours.  I see where you mean about the regulating of the clock as well... it has 3 "fingers" as you said.  Anyway... thank you and I hope this information will help you help me!  Thanks so much!

Answer
Hi again Cecil.
Three hours per day is a huge gain, and is way beyond the limit of regulation, so adjusting the regulating unit will not help. Your clock has a "floating balance" mechanism. The wheel should be revolving about 270 degrees, that is about 3/4 of the way around, then back the other way. 180 degrees, a half-turn, is marginally acceptable on an older clock. Most likely, the wheel is turning much less than that and the escape wheel is skipping over the verge. The escape wheel is a small brass gear with slanted, square-topped teeth, which you will see below the floating balance assembly. The verge is the anchor or fork shaped part with small pins on each end; the verge goes back and forth and releases one tooth of the escape wheel at a time. If the balance wheel's movement is insufficient, the verge will allow the escape wheel teeth to slip past it several teeth at a time, rather than crisply releasing one tooth at a time. Even if the balance wheel's movement seems adequate, the same sort of slipping can occur if the escape wheel and/or the verge are improperly adjusted. Readjusting these parts is not an option, as it would take me diagrams and several pages to describe this rather difficult process.
    Replacement "platforms" (balance wheel assembly) are available from clock materials houses for many of these clocks. They will be of the "balance wheel" type, but will be compatible with your floating balance clock. But, before you go out and order one: the root cause of all these problems is usually not in the balance assembly, but is due to excessive friction throughout the entire gear train, due to wear, dirt, dried up oil, or tired mainsprings. A clockmaker can overhaul your movement, or replace it with a new one. As a last resort, you could try lubricating all the pivot holes (where the gear shafts go into holes in the brass main plates), winding the clock FULLY (don't worry about "overwinding"), and seeing if there is improvement. This will not do anything for bearing wear, but it may help with dirt and dried oil.
   I hope this is helpful to you. Your clock movement is old, and you should keep in mind that it is probably on its last legs to begin with.  Thanks, Martin.