"Raising the bar" on modules, how to improve

The basic concept of modules is interchangability and ease to set up and tear down a layout.

A lot has changed since the first Zbend modules.

The ZoCal group has set up modules that have a mainline length of 10 scale miles.

I've got some observations on where I think we can improve. In the sections below I describe how "we" (ZoCal) does it, and some personal suggestions on how we could improve.

Note: the simple stuff is first, and the more complicated stuff follows. My goal is to do the easy/simple stuff first and then get into the more complex/controversial issues.

I'm trying to use 4 parts to each "topic"

Zocal implementation - overview of what we do that is different or "beyond" the Zbend standard

Issues - what issues we have, things to improve

How to improve - suggestions and ideas on how to improve

Details - more in-depth information.


Module legs

Zocal implementation

One large improvement has been the standardization of the legs for modules. Threaded knobs are used to affix the leg to the module and a threaded insert is in the module side. Simple, quick, effective. All legs are also equipped with leveling feet.


My only issue where I think we can improve comes from experience at shows: Missing knobs. The knobs are sometimes left in the legs, sometimes in the modules, and sometimes in a bag or box somewhere. A good solution will make it so we don't waste time looking around for the knobs.

How to improve

I was thinking of putting a circlip on the threaded shaft of the knob to make the knob captive. That solves the loss issue for sure, but  has other issues, hard to stack the legs, and harder to attach the legs to the modules. (The leg fits in so closely, you just need the threads "peeking out" of the leg to get into the threaded insert.

Jeff Thompson came up with a simple, elegant suggestion, drill a lengthwise hole in the top of the leg to store the knob. Now they can be bundled up in groups, stacked neatly (since the knob is about the same diameter as the leg) and when stacked up, it's clear if a knob is missing from the "forest" of legs.

Details on the implementation:

Need to fill in:

  • leg size:
  • xx" hole drilled xx" from the top
  • hole drilled in top to store knob
  • leveling foot is xx" long
  • knob specs

Module joining / alignment

Zocal implementation

We use threaded knobs. We found bolts too much work, need a wrench. Wing nuts could not get enough pressure by hand. We have found that holes closer to the top of the module result in better module alignment.


Biggest issue is that nothing lines up! Seriously there's a number of factors here. The Zbend standard has a good "core" idea of measuring from the center of the module, but from a practical aspect, when modules are built this way, then you have 2 measurements from the center to align tracks, where the real issue is that all 4 tracks need to be aligned to each other, not a center.

Another issue is that the holes to join modules are not in the right place to allow the tracks to be aligned.

A final issue is that since there are inaccuracies everywhere, the holes need to be large enough to have some "give" when aligning, and some are too small for the newer, larger diameter threaded knobs we are using.

How to improve

The first thing that makes sense is get the holes and the tracks all in the proper relationship. We need a template that can easily and accurately point out any problems.

Details on the Implementation:


Module electrical debugging: main lines

Zocal implementation

describe the current mounting, specs, using knobs


How to improve

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