It is with great sadness that we report Harvey Robinson, owner and operator of Essex and Lakeside, has passed away on Sunday, November 15th 2020.

The original title of this write-up was “Turntable”. I thought that hit the spot precisely. An engineering title for an engineering article describing an engineering problem and solution. What else is there to say? Christa edited this article, corrected my mistakes and finally said that my title is (bleep)-ing boring and changed it to what you see now. Thank you. The rest is mine.

The crudeness of early twentieth century engineering, the raw metal and exposed mechanics have always fascinated me. Steam engines, with their open driver mechanisms, pipes, and valves, are a thing of beauty. Nothing hidden behind streamlined sheets of metal. I always knew if I ever got around to building a layout, I wanted to model that time period. Originally, I had the early 1920s in mind, but the commercial availability of models that I wanted, pushed it forward to 1935. The Pennsylvania Railroad had what I wanted in locomotives, and it fit my industrial theme of coal, coke and steel making. When looking for a turntable, I first looked at the largest steam engine the Pennsylvania Railroad had, even though that locomotive came years after my chosen time period. This would allow me to change the time setting of my layout later if I wanted to. The PRR also had long-haul tenders, adding to the overall length of the locomotive. Those engines plus tender can be 124 feet long.

Walthers offers a 130’ turntable and Custom Model Railroads has a 135 foot turntable kit. Both can handle the largest PRR steam engines with a long tender. I opted for the CMR kit mainly because I like to build things. I didn’t want to just build the kit; I also wanted to build my own turntable bridge drive mechanism and the electronics to control it. I figured that would be easier to do with a kit than the ready-to-run model from Walthers, which may be locked into using their own motor and control unit.
I dragged my feet getting started with the kit. Mainly because I thought it would be complex to build and is such a central, high visibility element of a yard. But it got to the point where the upper level of the layout is getting closer to being operational and now needs the turntable to turn steam engines and make the yard functional. Turns out, the CMR kit is very simple to build. The picture below shows the wall units glued on the base. The wall pieces are quarter circles that are staggered and aligned with small tubes that are sticking out around the edge. The pit flange is not glued on yet.

Photo 1: Turntable Pit

The next photo looks down the yard. I plan to have two approach tracks and the stubs are visible in the lower right corner. When the turntable is in, I can lay those two tracks and complete the yard. Well, almost….the roundhouse tracks also need to be installed. The paper cutouts have some sketches of roundhouse doors on them to give me an idea of the track spacing. They also include the rough positions of the coaling and water towers. Due to the backdrop being so close to the turntable, only the tracks to the right and left of the turntable will be usable for engine storage. Electric engines (P5a, GG1, MP54) will be stored on the three tracks visible on the right.

Photo 2: The Yard

Photo 3: This picture shows the flange glued onto the pit walls. The turntable will be raised so that the flange is level with the surrounding ground.

What you see under the turnouts is paper. The turnouts are scratch built using the FastTracks jigs, but I didn’t want to use their turnout tie assemblies with main line tie spacing in my yard. Instead, I glued the ties on my own paper templates with proper yard tie spacing. That paper is now shining thru until it will be covered up some day.

The CMR kit instructions say to power the pit ring rail. The trucks that the bridge rides on pick up the power from there and feed the track. I had some serious reservations about that idea. Primarily, because I figured this may become unreliable over time and cause audible interruptions in sound equipped engines. It ruins the illusion when an engine goes through the sound startup sequence multiple times. I wanted something bulletproof. I also wanted to have an LED in the bridge control cab. I didn’t tap into track power to power accessories or lights anywhere on the layout, and I didn’t want to do it here. Therefore, I needed four wires going to the bridge, and they somehow needed to go thru the shaft.

I searched the Internet and found an idea that I liked. The rest of this article describes the solution to my problem.

Photo 4: I held four copper washers together with a clothes pin and let the solder melt in between. I needed four of those, one for each wire. I coated one side of the copper washer with solder flux, then stuck another washer on top. I coated that one with solder flux as well and stuck a third washer on. One more time and I had 4 washers together.

Photo 5: To route the wires thru the washers, a series of holes must be drilled through them. I drilled the first one with my Dremel tool. But the copper washers got so hot that the solder liquified and the washers separated as shown in the photo above. But at least it proved that the solder flows nicely between the washers. Then I tried drilling the holes first and then soldering them together, but I had a hard time lining up the holes. I ended up drilling the holes by hand after I soldered them together. The first ring needed four holes, the next one three, the one after that two and the last one needed one hole. That wasn’t too bad to drill by hand. I should have used wider washers, though. Drilling a 1/16 hole through them was very tight.

Photo 6: Here I am test-fitting the assembly to see if the rings sit tightly on the plastic tube and the tube on the brass shaft. The stepper motor on the right is coupled to a brass shaft. Over the brass shaft goes a clear plastic tube and the washers are slipped over it. The copper washers are electrically insulated from each other by nylon washers. The bridge will sit on top of the shaft with another coupler in between.

Photo 7: After I drilled the holes and test-fitted them, I sanded the copper rings smooth to minimize friction and maximize electric conductivity. I cut the head off of a screw, so I could clamp the copper rings between two nuts and use a hand drill to run them over sandpaper.

Photo 8: Four wires are routed through the drilled holes. The yellow wire goes to the first, right-most copper ring. The blue wire goes through the first copper ring and is soldered to the second copper ring. The red wire is soldered to the third ring and the white wire goes through all of the rings all the way to the left-most copper ring.

Photo 9: Here the rings are pushed together. The four wires will be routed through the center of the shaft up to the bridge. I will probably glue the rings to the clear plastic tube, so they won’t move over time.

Photo 10: I also bought the motor mounting kit from CMR. The white plastic frames in the picture are part of that add on. Once assembled, it will secure the motor to the bottom of the turntable and make sure that the shaft will remain centered. The white plastic material is very ridgid and light-weight but also quite brittle. I handdrilled the holes through it, careful not to crack the material. Two PCBs are screwed to the frame. They will hold the connectors for the four wires. I am not sure if screw connectors or pins are better. I’ll probably do both to keep both options open. These are the connections to the DCC track power and accessory power bus for the LED. I will use my own electronics to toggle track polarity as the bridge turns.

I had some 0.51mm brass rods left over and they seem sturdy yet flexible enough to serve as wipers. They will be soldered to the two PCBs, forming an arch that pushes against the rings and establishes electric contact.

This drawing looks straight down on the assembly. There will be four brass rods, one for each copper ring. They are stacked on top of each other in this drawing, so only one is visible. They will need to be installed having some tension to push against the copper rings and make reliable electric contact. The motor has a 1:51 reduction gear and should have no problems overcoming the friction caused by this.

I am still working on putting this together. The software and electronics to control the turntable need more testing. And the two approach tracks need to be laid and wired. I may write a part II to this, once I get it all working.

Thorsten

I have been traveling for work to Alexandria in Central Louisiana for most of 2018 and 2019, typically Monday thru Thursday every other week. During one of our Tuesday Op Sessions Carl mentioned that he knows someone in Baton Rouge with a layout and that he would be happy to introduce me to the host. Long term members of the group may remember that Jim Lofland joined the group years ago when he was on a project assignment in the Boston area. Carl made the introduction and Jim and I exchanged email addresses.

It is a two-hour drive from Alexandria to Baton Rouge and I was hesitant to make the round trip during a regular Monday thru Thursday week. Being back at 1 AM in my hotel in Alexandria and getting up only 5 hours later didn’t sound very appealing to me. I was beginning to believe that the layout visit is not going to happen when my client requested that I stay over the weekend to support the production rollout of the solution we have been building for them. Jim and I agreed that I could come down on that Saturday evening. He invited his local operating crew and I was looking forward to an operating session in Baton Rouge.

The rollout for my client went (sort of) well and leaving the office early wasn’t a problem. As expected, there was no traffic on the highway until I reached Baton Rouge. Jim’s layout is in a large room behind his house, I’m estimating may be 20 x 20 feet. It is a beautifully finished layout with hand-laid track and many craftsman kits. I just love the way these wood kits look! Great attention to detail over 20+ years has resulted in a museum quality model railroad. If it hasn’t been featured in a model railroad magazine already, it certainly should be.

We were a crew of five people that evening and I had a great time operating on Jim’s layout. It was very smooth-running and a lot of fun!

Here are some of the pictures I took.

The layout is point-to-loop but operated as point-to-point. This is the yard at the point end. I apologize for having some of the images sideways. I tried to turn them but it wouldn’t stick.

We ran mostly diesel during the operating session, but Jim also has some beautiful steam. Here only partially visible.

Jim wanted a turntable large enough to turn a Big Boy. There was nothing available commercially at the time so he scratch built this one. It’s motorized, too.

The coal train was my first assignment. It runs around the entire layout with lots of set-outs and pick-ups.

The coal train has to switch empties for loaded cars at the power plant.

More work to do for the coal train at various industries along the way.

Many great switching opportunities.

This is the yard at the other end with the loop visible at the bottom. Now on the right because the image is sideways again.

A closer look at the yard.

The engine house.

My favorite – large steam. This one is a brass model.

Looking into the layout room from the entrance.

A closeup of two of Jim’s beautiful wood kits.

Jim’s layout is DC with block control. All of his turnouts are motorized. This is one of the many control panels located around the layout. Childress is a very interesting switching puzzle that I got to switch after running the coal train. The photo of the loop yard earlier also shows this switching area in its entirety from above.

Some close-ups of the area.

I don’t know yet where my next project is going to be, but I’ll sure ask Carl if he knows someone with a layout in that area.