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

Saturday, February 4, 2012

Sunset NSL Silverliners #6A – Couplers, Underbody, & Steps

Due to the length of this topic the post for the Couplers, Underbody & Steps will be broken into 2 posts. Two different methods to upgrade the couplers on the models are presented.

Before getting into the topic of couplers, some words on switching models of interurban passenger cars and making up trains. Initially when building my layout the idea of being able to make and break-up trains was an interesting concept. When the layout got to the point where cars and trains could be run, I found myself more interested in running individual cars or 2 to 3 cars in a train. The idea of switching was soon put by the wayside. This is the reason for using solid non-working couplers instead of working couplers. Many modelers may find this happening to them.

The switching of the replacement Liner cars becomes even more improbably when the fact the 415, a trailer, has to be electrically tethered to one of the powered cars for lights, unless you’re running the train on 2-rail. Chances are you will keep the 3 cars coupled together only to take them out of the yard to run as the replacement Liner 3-car train.

The most common complain I have heard regarding the Sunset Replacement Electroliner sets has been the couplers. Although Kadee couplers are nice, having them attached in a fixed location to an interurban car like a freight car is nonsense. As on many interurbans, the couplers on the NSL were radial. They swung freely from side to side. Changing the couplers on the Sunset models will not only make the models more prototypical looking but will decrease the operating radius of the models. My desire is to make the models operate on a radius of at least 18". The prototype operated on an O scale radius of 22.5" (90 feet prototype) on the Chicago "L". For street running you may desire to operate them on 12” to 15” curves. Tighter curves may cause problems.

The process of replacing the couplers is one to do on all 3 of the cars at one time. Before doing anything remove the pilot at each end of the car(s). They are held in place with 2 small metric screws. Place both the pilots and screws in a safe, secure location. The pilots will be one of the last items reattached to the models.

One of the hallmarks of the NSL was the unique smaller size couplers used on their passenger cars. Also, NSL passenger cars could not couple onto other railroad equipment equipped with knuckle couplers due to a difference in coupler height. If you desire to know more about this, most books on the NSL explain the reason for this "coupler uniqueness".

To make an informed decision on what to do you need to know what O scale interurban couplers products are available. The Current Line Models, the old Wagner Car Company, couplers available are #M-400 Kadee coupler pocket on a thin brass radius bar. You supply the Kadee coupler. (Reuse the Kadee supplied with the Sunset Models.) Kadee couplers are not in any way, shape, or form NSL looking couplers. Furthermore, if Kadee couplers are used with the M-400, the cars will probably be coupled further apart than the prototype NSL cars were.
Current Line Models Photo

The other coupler from Current Line Models is #M-404 Radius Bar with a soft metal knuckle coupler mounted on a stamped brass radius bar. The coupler is a representation of the standard knuckle coupler. This coupler is larger than the NSL passenger couplers.
Current Line Models Photo

The other supplier of radial couplers is Q-Car Company. Q-Car's products include #CB010 which is a soft metal North Shore coupler mounted on a soft metal radius bar. The coupler is close to the size of the NSL passenger coupler.
Q-Car Company Drawing

Above is a drawing taken from the Q-Car web site. The coupler did at one time come mounted on a thin brass radius bar. Now the coupler comes mounted on a soft metal radius bar (below) #CB010A which is also available separately.
Q-Car Company Drawing

So, this is how the Q-Car #CB010 coupler now comes.

Since the coupler did at one time come mounted on a thin brass radius bar, you still may be able to fine them. Concentrate your search in a traction modeler's parts bin or older hobby store inventories.

The other NSL coupler available is Q-Car’s #B135 Coupler North Shore w/Spring Hanger & Carrier as a set of lost wax castings. The coupler is very close to the size of the NSL passenger car coupler.
                                                                         Q-Car Company Drawing

O scale interurban couplers are also available from Precision Scale Models (PSC). Since these were designed for the Illinois Terminal; the couplers, hangers, and carriers are all oversize for use on NSL cars. They were not considered for this application.

Like with many things about these models, the choice of couplers and how to install them provides many choices. A friend Charlie Pitts decided to use the Current Line Models M-404 coupler. Charlie told me he has standardized on using Current Line Models M-404 couplers for all his traction equipment. You will see his installation but if you have any questions you'll have to contact him at

The Kadee couplers on the Sunset models are mounted with metric screws to a thick brass tab soldered to the back of the anticlimber. The original holes for the screws holding the Kadee are evident in the photo. Charlie has already drilled and tapped 2 holes (brass colored holes) to hold his new couplers to the brass tab. I think Charlie said he tapped the holes for 2 mm screws.
Charlie Pitts Photo

Here is another photo showing the end of the car after the holes have been taped.
Charlie Pitts Photo

If the stamped brass coupler radius holder is attached to the brass tab, a small spacer has to be used between the brass tab and the coupler’s brass radius holder. Without the spacer the coupler will not be able to swing past the brass tab. Note the curve in the spacer for the coupler to pass by.
Charlie Pitts Photo

Finally here's the coupler attached to be brass tab. Note the 2 places on either side of the coupler carrier to hold brake hose. When looking at the finished work look at how much room there is between the end of the anticlimber and the coupler's knuckle. While it may not look like a lot of space, it is more than on the prototype NSL cars.
Charlie Pitts Photo

Charlie's method is a fast solution to an almost overwhelming problem with the Sunset models. It’s a great idea and the couplers work. I do not have any close-up photos of Charlie's NSL models from the side, coupled together, to get an idea of coupler height or distance between cars.

Initially I was planning on installing lost wax brass couplers with air brake hoses on the front and end of the 3-car train with soft metal couplers between the cars. I wanted to basically do the same thing Charlie Pitts did but with NSL style couplers. My logic of what I was thinking and doing may appear a little disjointed as you read what was done. I was doing and learning as this part of the up-grading of the models was progressing. The decision to use the all brass coupler was reached after different things happened. Here's the start. This is the Q-Car coupler I was hoping to be able to use. Then I discovered Q-Car no longer mounts the soft metal NSL couplers on a thin brass radius bar.

Below is what Q-Car now offers in the way of NSL couplers. The coupler on the left is made from soft metal while the coupler on the right is a brass casting. The couplers are available as complete couplers or the parts alone. I guess Current Line couplers could be obtained, taken apart, and Q-Car NSL couplers mounted on the Current Line stamped brass radius bar.

A major difference between brass and soft metal castings is the strength of the 2 metals. Brass is stronger than the soft metal plus soft metal bends easier than brass. During filing and handling, the radius bar can easily be bent out of shape. Bending it back into shape may not always produce the flat radius bar you started with. This is why I wanted the stamped brass radius bar.

A factor regarding couplers to take into consideration as you read this section is the profile of the layouts over which your models will operate. My layout is a flat as a board! It has no vertical curves. This means the knuckles of the couplers do not have to slide up and down very much if at all. If you have a layout with a roly-poly profile, a layout with vertical curves, the knuckles need to be able to slide freely up and down past one another. If not, your train with experience problems.

How does this fit into a discussion of soft metal vs. brass? From experience I’ve found brass couplers do not have a lot of clearance in their design to allow the knuckles to easily slide up and down when coupled. On the other hand, soft metal couplers do have more clearance to allow the knuckles to slide up and down when coupled.

Which ever metal coupler you chose, the areas both outside and inside the knuckle should be filed to allow the couplers to slide over each other. More judicious filing inside the knuckle will allow for more clearance and the ability of the knuckles to slide pass each other even better.

I tried to mount the soft metal Q-Car radius bar the same as Charlie had done. (Photo note - On my models I have already cut off the brass tabs on the ends of the cars. Therefore, I'm unable to provide photos. You'll have to imagine what happened as you read this part.) There was little to no metal to hold the Q-Car soft metal radius bar to the brass tab with screws. Also, when the Q-Car radius bar was held in place on the brass tab, there was a "giant" void in the area from bottom of the vestibule to the radius bar. After looking at both photos and drawings of the prototype I realized this was an unacceptable situation.

An examination of the Q-Car brass casting radius bar shows the "bolts" in the casting which are the prototype bolts holding the radius bar down from the body of the car. At this point I decided to use Q-Car brass couplers between the cars as well as the front and end of the train regardless of the cost!

Stay tuned! The balance of the info will be posted soon.



  1. Ed - Great explanation of the choices. Thanks. Charlie Pitts

  2. Definitely learnt something new here. Good series of articles.