|ESCO Choker Bell
The occupations of Choker Setter, gandy dancer, pulling on the green chain, and digging ditches all have a common thread. They represent the hard entry level positions of the logging, railroading, sawmilling, and construction industries. Most likely many people think that a 'choker' is some sort of a women's necklace, but the truth is far from it. To a logger a choker is a short length of cable intended to reach around the log and connect it to what ever it is you are trying to hook the log to.
In a cable logging operation, the chokers will be attached to the carriage, butt rigging, or drop line depending on the way the side is rigged. In a ground logging operation, the chokers will be attached to the winch line. The old fashion way is to have a big hook on the end of the winch line called a "C hook" because of its shape. Each choker would have an 'eye' (loop) in its end and would simply be hooked over the 'C hook'. A newer way of doing things that became popular with the advent of the Log skidder was the use of sliding hooks. In this manner, each choker was connected to a steel ring like device that could slide freely on the winch line. Instead of putting a hook on the end of the line, you simply tied a knot in the end of the line so the sliding rings couldn't slide off the end of the line. This is of particular advantage if the machine operation is setting his own chokers. You can drag the winch line out to the most distant log, and then slide the chokers along the line from there back to the machine. This implies you can hook several logs in different places at the same time, and then wind up the winch line, and they will all slide to the end of the line, and finally even up and all drag together.
ESCO has the credit for being the premier maker of the hardware needed to make a choker. Shown in the photos here is a classic ESCO choker bell. The knob on the end of the choker is pushed through the side of the bell, and then turned to the end of the bell as shown in the photo on the right. The result is a slip knot type 'choker' around a log. It is easy to connect, hard to break, and rarely shakes freed even if the slack the line. This contrasts to the alternative style which was just a hook on the end of cable which you hooked back over the cable. Hooks, you see, often fall free when the line is slacked. Once one of these is pulled tight so it bites into the bark a bit, it will not come unhooked on its own (99% of the time). This is important because often in logging you have to slack the line for one reason or another, and if the hitches fell apart each time as they do with 'hooks' your blood pressure would be up very high.
|Skidder with fairlead
The choker, itself, is always made of a piece of cable that is smaller in size than the main winch line. This serves as sort of a 'fuse' or weak spot, so if the log hangs up and the rigging is going to break--the choker is the expendable item. The hung up log simply breaks free and the winch line is or main lines are spared. The absolute sizes of the chokers and lengths may vary on application. In High lead logging, a 20 foot choker is often used, because the length of the choker is all you have to reach off to the side to get a log that is not directly under the carriage. If the logger is being done with a log skidder often an 8-10 foot choker is used. It needs in every instance to be long enough to reach around the log, but not so long that the other end of it gets to the winch before the logs are lifted free of the ground by the arch. The 'fairlead' is the collection of rollers which the cable passes through on the top of the arch. It has rollers on all for sides so the cable will be on a roller no matter what direction it is pulling from. This aligns the cable with the winch while avoiding damage to cable by 'burning' it against stationary steel objects. The large hole in the fairlead means that rigging can pass through such as a 'C hook' or sliding hooks or what ever device used to interconnect several chokers to the winch line.
The chokers in a logging operation, though not cheap are more or less expendable. the choker bell itself can be recycled, so when a choker is broken, you save the bell and send it back to the rigging shop and have it put on a new pieces of cable. In times past, the 'knob' on the end of the choker was fastened on with babbitt. Nowadays, they are either wedged on or pressed on. As you might guess, the pressed on knobs are just that (and what you see in the photo)--a piece of steel squeezed on the end of the cable with a big press. Wedged knobs by contrast can be field installed. You slide the shell of the knob over the end of the cable, and then the strands of the cable are spread by the insertion of wedges between them. The knob shell is then slipped forward up over the tapered wedges and jammed. The classic solution is similar. You slide the knob shell over the end of the cable and spread the cable strands inside it, but instead of driving in steel wedges, you pour the end of the cable full of babbitt.
It some ways it may seem strange that loggers used babbitt for this, but in another sense it is not surprising. babbitt, you see, is a alloy of tin, copper and antimony notable for its low friction when turned against steel. It's most common use is for bearings. In the early part of the century, babbitt bearings were common on heavy machinery so the repair shops always had it around. Like solder it has a fairly low melting point, so when you needed to install a choker knob, you just heated up a crucible of it and poured the knob full. In a few minutes it cooled out and was ready to use, but alas, the days when every repair shop has a forge going all the time are long gone, and babbitt connected knobs haven't been seen in the woods for 40 years.