Hello All,

Question #1: I am building a TMCC layout for the holidays using a couple of Ross #8 switches to make sidings off the main line. What is the formula for calculating the amount of "curve" one needs to get back to a parallel siding? Straights are too straight, and curves curve too much! I've heard flex track mentioned but know nothing about it. I'd like the siding to be around 4 to 5" CTC from the main line.

Question #2: If I use DZ2500 switch machines, is the function of the DZ1000 just to transfer data from the Legacy 990 to the switch machines?  I'm assuming, one switch machine for each switch, and one "DZ1000" for the layout. Is that how it works?

Any help would be greatly appreciated. Thanks,

Lion L

Born in the land of coal...

Original Post

#8s for sidings? thats my kinda layout... but sadly i have no room for that. 

A #8 frog is just a tad over 7 degrees, so you'll need to match that if you want to get back to parallel. You can either cut a huge curve down or flex track it. Steve at Ross makes transition tracks for the Ross Regular 100 and 101 switches at different track centers, I dont think he makes them for any other switches but its worth a call to see what he can do. 

The data driver is a DZ2001, not a 1000 and you need one of them for the layout. Make sure you have the latest revision if you plan to use it with Legacy (I think its 'C'). The DZ2500s (at each switch) connect to it via a bus wire and then can be programmed and actuated via the remote or LCS wifi. You still need to provide 12V and ground to each machine. 


"Of course we know its O-gauge or no gauge." -- Sheldon Cooper

Thanks Boilermaker, 

That's a lot of the answers I was looking for. I was just trying to "eye-ball" the angle to get back to parallel, but there wasn't a single piece of curved track that I could use. I was beginning to consider sawing off part of a curved piece to get close, but I'm glad I asked! I am planning to check with Steve anyway before buying the switches anyway, but I wasn't quite that far yet. Thanks for all the info!


Lion L

Born in the land of coal...

A No 8 switch is pretty long.  Below is a diagram of the switch and track sections to get 4.5" parallel tracks.  Total length to parallel is almost 4 feet.

I used a O-72 curve to get to parallel so you can use the largest engines.  The curve is 7.5 degrees of arc to match the No 8 switch.  You can cut a sectional O-72 curve by measuring 4.71" (straight line) on the center rail.  Unless you have a lot of space, you can use a Ross regular switch (close to O-100)  and get good operation in less space, saving a full foot.  A No 4 switch (close to O-72) would save even more space.

Ross No 8





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Thanks Ron. I knew it must be pretty long, and I didn't have an O-72 curve to try. I'll have to get a couple to have on hand. I was able to get an O-54 switch to work in it's place for now. The diagram really helps to visualize the length. 

Born in the land of coal...

If you're using numbered turnouts (#5/11-degree, #6, #8) you probably don't want to use cut-down sectional curves to return-to-parallel. You'll get a better look just using flex track. Be prepared, though, to use the length of the straight segment of the turnout to make the curve. See the illustration below:


From top to bottom: #4, #5 (11-degree), #6, #8, and #10 Ross turnouts. The straight section following the turnout is equivalent to the length of the straight leg of the turnout. Spacing is 4 inches.

According to  Ross, the point radius on the #4 is 36" (O-72) to handle larger equipment. NMRA specs say it should be 33" radius (O-66) Tests with my scale-wheeled Big Boy indicate it won't work with large-wheelbase scale-wheel steam. The #5's handle my Big Boy and my scale-wheeled Hudson fine.

As you go to the #6 and beyond, the frog gap gets larger and will not support scale wheels without modification of the frog. We put a moving point in the frog on the #8 curved turnout on the club layout.


Matt Jackson
"The best service you can provide for the hobby is to pass on what you have learned."

 Angels Gate Hi-Railers San Pedro, California

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