I’ve been remiss. In the introduction to this blog on my home page, I promised I would share my triumphs as well as my failures. I think I’ve done a pretty decent job sharing the failures, but no so much in reporting victories. Let’s fix that!
About eight years ago, Sally bought a funky clock that displays a set of moving gears and has no hands. What it does have is a black arrow that is fixed in its position pointing up towards the ceiling and a wheel with the hours marked on it (with 3 marks between each hour to denote 15-minute intervals) that makes a full rotation every 12 hours.
(If you are reading this in an email, I strongly encourage you to go to the website here to see a picture of the clock, as my descriptive powers and your imagination will only carry us so far!)
Instead of two hands that move across the face of the clock in a clockwise direction, then, it has a clock face wheel (separate from the rest of the assembly) that is placed on one of the gears which moves it in a counterclockwise direction. To set the clock, you place the wheel on the gear so that the fixed arrow is pointing at the correct time. For example, if it’s 3:15, you would place the wheel above the arrow at the first hash mark between the 3 and the 4.
We hung the clock on the wall in the office but, to our dismay, it ran fast. So fast, in fact, that we would have had to re-set it every day if we wanted it to be of any use in telling time. Instead, we just left it in place and let time stop when the batteries died.
Fast forward to last month when Sally took the clock off the wall, packed it and brought it to our new apartment. There was a perfect spot for it and we were eager to hang it. To be honest, I had forgotten that it didn’t work, but it is such a cool design that I decided to spend a little time trying to figure it out before putting it up.
Looking at the control mechanism for the first time, I realized that all of the visible moving gears were for show. They had nothing whatsoever to do with rotating the clock face and, of course, there were no hands that needed moving.
There were 2 hidden gears engaged in moving the time-keeping wheel, one larger than the other, and that was it. Fascinating!
On my next trip to the supermarket, I bought 2 D batteries. In a world dominated by AAA and dime-sized lithium batteries, I got a kick out of dropping these two big old clunkers into place. As soon as I did, all the gears went into motion.
I hung the base with all its moving parts on the wall and then settled the cogs of the clock face wheel onto the larger of the 2 drive gears…and waited.
The next morning, I awoke to find the clock was already half an hour fast. Bummer. After thinking about it for a while, it occurred to me that maybe it would slow down if I placed the wheel on the smaller of the 2 eligible gears. In fact, that was my only other option.
I tried to think through why that might work, but to no avail. I hadn’t ever tinkered with clocks and so I had no prior knowledge about gears to draw from. I never owned a 3-speed bike, either, and so I didn’t have the opportunity to learn about gears that way. I just couldn’t see why the smaller gear would turn the clock face wheel more slowly, but, hey, it couldn’t hurt to try, so I moved the wheel to the smaller gear…and waited.
The next day there was substantial improvement: the clock was only about 4 minutes fast, which was better, but not quite good enough. What now? I was out of gears to try.
I spent about half an hour at the kitchen table just looking up at the clock. It finally occurred to me that maybe if I added some weight to the bottom of the wheel it would slow it down because the battery would have to work harder to move the gear. Intuitively, it made sense.
A few minutes later, though, I realized I might be in trouble if I added weight to the bottom of the wheel because it would be out of balance as the wheel rotated and the weight was no longer directly under the gear. Hmmmm…
…but if I put weights at the 3, 6, 9 and 12-hour marks, then the wheel would be balanced throughout its rotation. Problem solved.
At that point, I don’t think it took me more than a minute to come up with the idea of using quarters as my weights. So I got out the duct tape and affixed two quarters to the back of the clock face wheel at each of the four locations, set the wheel back onto the smaller gear…and waited.
The next morning, I awoke to discover that the clock had kept perfect time! It’s now a week later and the funky mechanical analog clock is keeping the same time as my computer’s digital readout.
This was truly a high-five moment for me because I have next to no mechanical abilities at all. I just don’t have that gene. So to think something like this through and come up with a solution that worked was quite the cognitive victory.
But what about the thought process that led me to the answer? Was it just luck? Was I the proverbial broken clock that was right twice that day?
Reflecting back, I realized that most of what happened was intuitive. Or, at least, it seemed intuitive. At the time, I could not verbalize why the smaller gear would slow down the clock (although I did figure it out several days later). It seemed logical that weight would slow the turning of the gears. Did I have some long-forgotten experience that taught me that this was true? And the decision to use 2 quarters instead of 1 or 3? It wasn’t based on any kind of formula or algorithm; it just felt right.
All of which raises another question: Why ask why? What matters is that I fixed the clock and it was a nice victory. I’ll take it!
BTW: It’s now 8:30pm. 😀