To paraphrase Vane Jones, "Knowledge is of little value until shared with others."

Tuesday, March 11, 2014

Trolley Pole Primer - Part 2 The Pole and the Fittings at the Top of the Pole

Before staring the material of this post allow me to make editor's comments. In mentioning any manufacturer I am not endorsing or attempting to push the manufacturer's products. I have at all times tried to remain neutral regarding the hobby manufacturers and their products. However, in writing about my experiences in all fairness to the readers of this blog, I do have to point out the positives and negatives of an item, process, method, etc.

Depending upon the topic of the post manufacturers, suppliers, painters, and various other individuals who have been involved in the trolley end of the model railway business in the United States will be mentioned. This is done to fill in any voids which may appear. My sole purpose is to provide information. It is up to the reader of this blog to use his or her discretion in obtaining goods and services just as in buying an computer, furniture, personal goods and services, etc.

Trolley poles themselves are hollow tubes. If they were not hallow, but solid, they would weigh too much to be supported on the roof of the car.

Some of the poles were a tube like a pipe while others were tapered at one or both ends. For most O scale poles a piece of phosphor bronze wire is used. As far as I know only the Precision Scale trolley pole is a brass casting and is tapered.

Trolley poles come in various lengths. Cars carrying only a single pole mounted in the center (length) of the car are longer than normal. Normal, if there is one, is 12 to 14 scale feet.

The concern is, is the center of the mounting point of the trolley base in the correct position for the car. This should be determined from either plans or photos of the prototype car. In the past articles about what is the correct location of the center point of a trolley pole base have been written.

PE had the 800-929 series of double truck cars which as originally built had only 1 trolley pole. When the subway was built, in order to reverse the direction of travel of the cars, because there was not sufficient room to walk the single pole around to the other end, the cars were double poled. This is mentioned as there has to be some allowances in the exact, required center point location of a trolley base.

Even if you obtain the model built-up and finished by a reputable manufacturer check the centers of the trolley bases for correctness. For example, the CA&E Cincinnati passenger cars made by St. Petersburg Tram Collection did not have the trolley bases mounted in the correct position. The mounting points have to be changed by the modeler.

Furthermore, sometimes the length of a trolley pole has to be adjusted to the car on which it is used. More on this later in this post.

Next comes the strange thing at the end of the trolley pole - the most common are either a trolley wheel or a shoe (slider). Sometimes a "V" shaped object is fitted called a sleet scraper. Another object used is a "greaser" or an "applicator".

Originally a 10", 12" or larger diameter wheel was used. Initially the wheel would rotate but over time it would be worn into a hexagon shape with the wheel sliding along on one of the planes of the hexagon. Over time the trolley companies discovered smaller size wheels could be used.

The slider was an invention based on the wheel worn into a hexagon shape. As you will see there are many sliders which were invented by the manufacturers. The advantage of the slider is it can provide better, continuous contact with the trolley wire thereby providing for more electrical current to be transferred from the trolley wire to the trolley pole.

The disadvantage of the slider is the trolley wire has to be lubricated to prevent premature wear of the wire. This is the reason for the "greaser" or "applicator" at the end of a trolley pole.

Another disadvantage of the slider is the potential of the slider catching the trolley wire during back-up (reverse) moves of the trolley car. Care has to be taken during back-up moves. Normally the opposite trolley pole is raised during back-up moves. The trolley wheel is better for switching where the car moves back and forth with a trolley guide, a human holding onto the trolley rope.

How does all of the above apply to the modeler. Before you order poles from a manufacturer find out if you can get the length of the pole made to order. Since PSC has a pole kit, you can cut the pole to any length you want.

Already mention has been made about the pole fitting the model. Single truck cars often had longer than normal trolley poles mainly for ease of hooking down the pole. When I was working on a model of a North Shore Line coach, I was surprised to find photos and scale drawings which showed the trolley poles did not extend over the ends of the car.

This photo shows the trolley pole of the NSL coach (model on the left) sticking out over the end of the car and above the roof of the model on the right. The poles on this car had to be shortened.

I replaced the trolley poles on a Sunset model of the Electroliner for a friend. I was surprised to find out how short the trolley poles were. The trolley poles on a North Shore standard passenger car or Electroliner could not extend out too far or else they would foul one another on the sharp curves on the Chicago "L". This photo is a comparison of 2 trolley poles. The pole at the top of the photo is from an NSL coach (not the one shown above). The pole at the bottom of the photo is from a Sunset Electroliner. The Sunset slider has been replaced.

When it comes to the end of the pole, a sleet scraper should never be applied to the end of a pole unless the pole is a dummy model of the prototype. The sleet scraper is in a "V" shape and intended to scrape the sleet off the wire. On a layout it could snag the overhead wire and ruin the trolley operation.

While  know there were other sleet scrapers used, the "V" shape is the only one I've seen in person.

The "greaser" or "applicator" applied, depending upon the trolley line, a mixture of beeswax or paraffin, mineral oil, and graphite onto the trolley wire once a week or so. It lubricated the trolley wire for the use of a slider or shoe current collector.

About 1954-55, Rich Wagner experimented with a current collector on the end of a trolley pole to lubricate his trolley wire. See Trolley Talk #2. He sold the device with the idea, the modelers who purchased it would report back on how well it worked.

Today, some modelers use liquid lock lubricant which is graphite in an alcohol mixture. Neolube is a similar product. Either can be applied once a month or so depending upon how many trolleys are operated off the trolley wire. Graphite being pure carbon is an excellent conductor. Also, depending upon the metal, the graphite adheres to the crystals of the metal for a period of time providing long lasting effects.

The wheels provided by the scale manufacturers mimic how a trolley wheel looks. Except for the PSC trolley wheel they are non-rotating. The other manufacturers provide the standard NMRA 6" diameter x 3" wide wheel. Q-Car also provides a scale size 5.5" diameter x 1.5" wheel.

The photo shows the NMRA wheel, scale size wheel, and the working wheel.

The PSC working wheel comes as 2 brass castings. Time is required to clean up the castings, increase the depth of the dimples to hold the wheel's axel, squeeze the ends of the harp to hold the wheel, and finally install the wheel on the trolley pole.

This PSC scan below may be out of order however, it offers a few different visual explanations of some of the unique features of their trolley poles.
1.Starting on the left notice the "exploded" view of the trolley base. The "stud" sticking straight down means the pole has to be installed using the insert mount type of installation. 2. Next notice the trolley wheel and yoke. If you obtain older castings, after Kemtron sold out to PSC but before a few years ago, the castings were not as good as the Kemtron or the newer PSC castings.
3. The trolley shoe is next. After cleaning up the casting check the depth of the hole for the trolley pole. You may have to drill the hole to a uniform depth. I do not have any particular depth in mind other than the slider should be square on the trolley pole.
4. Next look at the roof bushing. You can use this bushing or one you make for the roof of your model.
5. Not shown are replacement springs. They are shown on the same page as the trolley pole. Do not be thrown off by the erroneous numbers shown in the listings.
6. The trolley base is lost wax castings. I have found them to be too fragile for operating trolley poles. I've installed them on non-operating models used for presentations or the shelf. That said, some modelers have not had problems with the PSC poles in operation.

All the work  which goes into making the PSC wheel work is well rewarded as the trolley wheel rotates as the model goes by. I have PSC operating trolley wheels on a few cars. They work equally well going forward or in reverse. For individuals who do not believe the wheel rotates, the model can be slowed down to show them.

From the 4 manufacturers, 3 different sliders are available. All the sliders are brass castings. Some modelers prefer the Wagner sliders because it tends to give the most amount of contact area with the trolley wire and least amount of de-wirements. The photo has the brass casting and the casting after chemically darkened. 
 
This photo is a Wagner slider on the trolley wire. It shows the amount of shoe contact with the wire.
 
 
The Wagner slider is a non-working in that all the sliders were made so the shoe would rock back and forth in the slider body. This would allow the angle of the shoe to conform to the trolley wire. Actually, the Wagner slider is patterned after a slider where the shoe could rotate counter clockwise (per the photo above) when the pole was used in a back-up move to prevent the shoe from snagging on the trolley wire.
 
If one is careful, cars can be backed-up using a pole with a Wagner slider. The back move must be very slow. At the 1st sign the slider is going to snag the wire - the wire tends to go up as the slider is caught - stop the model!

The slider available from Q-Car Company looks to me like the style of slider the Chicago Aurora & Elgin used on its equipment. Two photos are of CA&E cars. Take a look at the sliders on the end of the trolley poles. If the sliders are looked at close enough, space can be seen through the part of the slider holding the shoe.

The Q-Car Company slider as a brass casting and as chemically blackened. The casting comes with a sculptured out portion resembling the area in the CA&E shoes where light can be seen coming through. 
 
This is a Q-Car slider on the trolley wire. The amount of wire contact is seen.

The slider available from PSC looks like the style of slider used by the North Shore Line on its equipment. Compare the sliders in the photos below with the PSC graphic above and photos below.

The PSC slider as a brass casing and after chemically blackened.  Normally the casting is flat in the area under the shoe. As the hot casting cools the metal contracts leaving the cheeks slightly pulled in.
 
This is a PSC slider on the trolley wire. The amount of contact with the wire can be seen.
 
Finally; springs, trolley wheels, and trolley sliders are available individually from the manufacturers. Springs can be obtained with different "pull" on the trolley pole. This translates into different pressure on the wire.

The availability of springs and trolley wheels and sliders means you are able to repair trolley poles. More on this and other info on trolley poles in the next post.


Cheers,
Ed

No comments:

Post a Comment