In the past few months I've completed 99% of the trackwork on the railroad and have been holding off posting photos until more of the scenery is in (blame N&W Chris Smith for setting a standard I'll never attain). But last week I did resolve a construction issue with my lift section that you may find interesting.
To gain access to my walk around design railroad (around the walls and 3 folded peninsulas down the middle) I build a lift section that includes 3 Middle Division main line tracks and a fourth off a turnout to the Tyrone and Clearfield coal branch. The benchwork at the hinged end of the bridge is fastened to a wall, while the opening is at the end of a 43’ long stretch of benchwork. Despite the basement being well insulated and climate controlled there is enough change in humidity between summer and winter to translate into approximately 1/8” movement in the overall length of the long run of benchwork. Since the track turns 90 degrees approaching the left section, a 1/8” shift in benchwork length gives rise to complete railhead misalignment. For a couple of years I coped with this by shifting the flex track approaches on the open end with change of season. A minor pain but not workable once the track is ballasted.
As an overview, below is a shot looking into the room accross the PRR Middle Division 3 track main.
One leg of the Tyrone and Clearfield branch line "Y" junction at Tyrone has a turnout on the lift section. The other leg is past the station area and has a pair of interchange tracks. Looking down the aisle you can see the T&C branch climbing to the end of the aisle where it crosses at 76" elevation and then back down past the mining town of Roberts, PA seen across the aisle from the lift section. As a side note the mining community was named in memory of past NMRA president and close O scale friend/neighbor John Roberts who passed away last month.
This view looks across the lift section toward the open end. The T&C branch and the work in progress town of Tyrone PA is to the right.
The photo below is looking railroad east toward the hinged end of the lift section.
I needed a solution that could address the seasonal movement of the benchwork, assure track alignment, and provide an easy to use locking mechanism.
Here’s what I settled on: I first machined one of the two hinge pins so that the lift section had a limited range of lateral motion. (Vertical motion at the open end was restricted by two robust horizontal tabs extending off the bridge). With a 30” lift section it didn’t take too much reduction in pin diameter to provide approximately 5/8” range of lateral motion. With the added “slop” the bridge could be pushed so that all 8 rails align vertically and horizontally – what I needed was a mechanism that could draw and lock the lift section into alignment. My solution was to purchase a pair of low cost ½” self aligning bearing pillow blocks on eBay. With a gunsmith friend’s help we used emery paper to polish a ½” drill rod shaft so that it could slide latterly in the pillow blocks. The rod was cross drilled for a 1/4” throw handle and tapered at one end. The range of motion is constrained by locking collars and cushioned by rubber grommets found at Ace Hardware.
This view is of the underside of the lift section showing the slide bolt mechanism. Also shown is the stall action turnout motor and frog powering micro switch. I probably should cover it some day.
At the open end of the benchwork I mounted an 3/16” aluminum plate with a ½” hole to serve as a the receiver for the tapered shaft.
Micro switches kill power to the tracks approaching the lift section when the bridge is in the up position. While the mechanism is a little on the heavy side it works beautifully. A secondary advantage is seeing the look on the faces of visiting HO and N scale model railroaders. Now back to ballasting the main.
Ed Rappe
Below I’ve added a few more shots of construction in the Tyrone area. My next project is to widen the Atlas HO single track truss bridge to serve as a highway bridge across the Juniata River just behind the station. I hope no one from the Tyrone area critiques the station and town layout. I took a lot of modeler’s license to fit it into available space. On the prototype the PRR’s Bald Eagle the Tyrone and Clearfield branches shared trackage in joining the Middle Division 4 track main line at Tyrone. Also not modeled was the very large (and aromatic) West Virginia Pulp and Paper mill. I’m ok with the compromises as the T&C coal branch operation and interchange with the main can keep several people busy for quite awhile.
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