Half a Test Turnout

You’d be excused to think that it’s a little late to go testing my planned turnout construction. But well, I’m changing it up yet again on this layout, and the Proto:87 posse was in danger of passing me. So, we raced ahead with everything else before finalizing construction techniques. If it doesn’t work out, I can always retreat to PC board ties!

Turnout half done

On my previous P:87 turnouts, I buried PC board under the ties, and soldered the rail to tiny studs between the ties. I then applied details, such as rail braces and bolts etc. This enabled me to avoid PC board ties, making the colouring of the ties a cinch. It was laborious, but even worse, if a solder joint failed under the ballast, it was very difficult to fix. Nowadays, painting wood or plastic to match adjacent wooden ties doesn’t worry me as much as it once did.

As might be apparent from some of my other writing (see, for example, http://proto87.org), I have been thinking about 3D printing for our hobby for some time. While it’s still somewhat pricy, turnouts are a perfect application for this technology. Looking at the hobby store shelves, you’d think turnouts only come in even frog angles; in reality, they come in every angle except #13. The reason you can’t buy a #7 is that it’s not that different from a #8 or a #6, and a manufacturer who created them would simply cannibalize their #6’s and #8’s. With 3D printing, you could create every possible configuration. You could even create custom lap switches, three-ways with mixed frog angles, you name it!

Then there’s the details. When there is no train in the scene, the track is the only thing that tells the viewer they are looking at a model of a railroad. Track is a model too. Unfortunately, every railroad had their own ideas about track, and those ideas changed over time! A CPR turnout from 1900, which may have lasted into the 80s, would have very different hardware from one built or renewed in the 1940s, and also different from a GTR turnout from 1900. With 3D printing, we could have all three!

I did a couple of experimental prints through Shapeways. The frog area turned out prohibitively expensive for me, and I can’t see how to fit the closure rails to printed wing rails without going crazy. So, despite very cool detailed guard rails and wing rails, I abandoned the idea for now. The switch is a different matter; I like the idea of printing slide plates and rail braces in place, and I think it shows promise.

The first switch we (the Posse) did was for Julian Watson’s Victorian Railways 5’3″ gauge layout. The VR rail braces are lower than those on the Canada Atlantic, and don’t contact the web of the rail. The test run worked great.

Victorian Rys Points PoC

The Canada Atlantic rail braces are the more complex variety that do contact the web of the rail. The Shapeways Frosted Detail material does a passable job of recreating these little cubic 1 mm blobs without being too expensive. Indeed, the design needs to be refined so there are no square edges.

Test turnout with Shapeways switch ties.

On Monday, Andrew came over to work on a test turnout. I chose a scrap of 1/2 inch plywood, and drew the center lines upon it, just as we did on the layout itself. Then, because we wanted to make progress right away, we sprayed the board with adhesive and laid the ties. I do not recommend spray adhesive for laying ties: you only get to position them once, except the printed ones, which don’t glue at all!

Test turnout with Shapeways switch ties.

Andrew scraped away the adhesive under the switch, and we used CA to fix it down. I then sanded the wooden ties lightly until they matched the PC board ties in the area of the frog and the heel of the switch. This turned out to be an error as I knocked a couple of rail braces off the switch through over-zealous sanding; sanding should come before the detailed parts. The PC board ties are from Fast Tracks, but I created wooden shims to make them nearly the same height as the wooden ties.

Finally, emboldened by the success with the VR switch, we laid in the straight stock rail. We marked the base of the rail for tinning over the PC board ties, and put down Pliobond for the wooden ties. The normal soldering iron is missing in action, packed away for the renovation, and so we used the resistance soldering unit. This worked better than I expected.

Only then did I think to check the actual gauge through the switch, and found it was tight. Shucks! Time to quit for then night and think.


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