Turnout Turmoil

So having a background as an architect, combined with a lot of years as an architectural model builder, has left me with a rather critical eye for detail and accuracy.  As the layout started coming together, I couldn't help but keep looking at the Model Power turnout motors and thinking there had to be a better way.  As you can see, here's a 40' box car in comparison to the turnout motor:

Where would you ever see a 40' long x 5' wide mass along side a railroad track? No where!

I started doing a lot of research and found there were numerous ways to control the turnouts.  Most of them were expensive.  Multiple expensive (about $30 per) times 14 turnouts = too much $$$.  Relying on the ever useful N Scale Net site, I cam across the process of using model airplane mini servos to control the turnouts. I looked at Tam Valley Depot and saw they looked to have perfected the process.  They had a great article in the July 2009 Model Railroad Hobbyist Magazine that really showed the entire process.  I was also really impressed that Duncan (Tam Valley owner) pointed out, on his site, that you could get servos off Ebay in bulk for lower costs.  He even described what to get off Ebay.  Amazing!

Fortunately, I have a few extra turnouts and can do a little research without sacrificing the layout.  I started by pulling one of them apart to see how they were built.

Underside of the actuator mechanism

The first thing I noticed was that the Model Power turnouts were built a little different than the Atlas version.  Even though there was a slide activator for the tracks, it was a really short piece.  I found some great info on the servo method from Jeff over on N Scale Net who shared some pics as well as his diagram:

Server under layout and brass guide tube

Notice the longer actuator bar on the Atlas turnout

Jeff's actuator mechanism

Looking at all this, it looked like a fairly easy solution to controlling the turnouts.  I went ahead an ordered an Octopus Controller (can handle 8 servos), one servo and a fascia mounted actuator button with dual LED lights.  I wanted to be sure that the system will actually work, although Duncan from Tam Valley swapped a couple emails with me and gave me some pointers that let me feel like everything would be good.

Since the slide activator bar was so short, I considered having the wire run under the turnout and come up to the bottom of the slide activator:

Slot and hole added to the bottom of the actuator bar

Slot test with wire test

Although the slot system worked, adding the wire quickly revealed that this wouldn't work.  There's no way the wire would twist on axis and still move the turnout.  That led to what will, in all likelihood, be the final solution - a .040 (same thickness as activator bar) x .25 styrene extension:

The only critical issue with this solution is getting a really good bond between the styrene extension and the activator bar.  There's only a little less than 1/16" of activator bar exposed when the turnout is thrown, so no real way to lap joint.  I use SC-125 acrylic adhesive which is sort of like super glue on steroids.  It's the same consistency as water and dries in about 5 seconds.  So far, 50 - 50 on confident bond.  There won't be a lot of torque on the extension but it needs to be stable enough so as not to have a continual problem one the turnouts are in place on the layout.

Next phase of this will be the actual op test with the Tam Valley products, which are due in this week!