Positional timing is adjusting a watch to keep a near-zero rate in more than one position, so what are those positions? Quality pocket watches, like the great American railroad pocket watches, were typically adjusted to 5 positions. We’ll learn those positions here, using Jendritzki’s abbreviations from Watch Adjustment.
The Horizontal Positions: DU, DD
The first 2 positions are horizontal: dial up (DU) and dial down (DD). The horizontal positions are also known as the lying positions. The process of adjusting starts with getting the rate to be as close to zero as possible between DU and DD. If the watch has different DU/DD rates—like +5 DU but -20 DD—then one of a great many things is amiss.
The Vertical Positions: PU, PR, PL
The next 3 positions are the vertical positions, also known as the hanging positions from back when watch timing involved hanging a pocket watch in a timing rack.
A watch adjusted to 5 positions will adjust 3 vertical positions.
The first vertical position is pendant up (PU), sometimes called crown up. When a pocket watch is adjusted to 3 positions, it is adjusted to DU, DD, and PU because PU is the most common vertical position. A railway worker keeping his Illinois Bunn Special in his front overalls pocket will mostly have the watch in the PU position.
Our second vertical position is pendant right (PR), defined from the perspective of someone looking at the dial.
And our third vertical position is pendant left (PL).
So, dial up (DU) and dial down (DD), along with pendant up (PU), right (PR), and left (PL), give us 5 positions.
The Infamous Sixth Position
For pocket watches, position 6 is pendant down (PD), an odd position for any pocket watch. My Waltham 1883 looks decidedly uncomfortable.
Many high-grade pocket watches were adjusted to all 6 positions. As we’ll learn later, achieving close time in all 4 vertical positions is much harder than the typical 3 (PU, PL, PR). Watchmakers in fact would design many mechanisms to “throw the error” into the sixth position, so even a well-adjusted watch can show poor time in the position six. The watchmakers adjusting those Bunn Specials to 6 positions were among the best of the best.
As an aside, notice that pendant left (PL) and right (PR) are relative. Throughout this blog, we’ll follow Jendritzki and define them relative to the dial side. When working on the watch, you’ll face the mechanism side, so you’ll need to flip the watch in your mind. PL on the dial side is PR on the mechanism side, and vice-versa.
The 5 positions for pocket watches aren’t the same as the 5 positions for wrist watches—we’ll learn those next.