The Transcontinental PRR

[peteski]

Wouldn't removing coupe of plies on the bottom of that plywood ledge give you plenty of clearance.  I think even at half the thickness, the ledge would have plenty of strength to support whatever you are planning on being there.

[GaryHinshaw]

However you achieve it, you definitely want more clearance than that.  As soon as one set of cans is not properly seated in the well - bam!  Nice start on the helix though.  There is one of those in my very near future too.

[DKS]

The cars flow through with no problem, although the visual is a little jarring.

More than just a little visual jarring... one out-of-round wheel, a container not seated all of the way, a derailed car, some settling, swelling or warpage of the wood, or any one of a host of other irregularities could create some serious issues.

[eric220]

Believe me, this is not the final vertical alignment. That's just a constant 2% grade from the starting point that I already have. Given that there isn't quite a full turn to that close clearance, I was thrilled that getting it to this point was just a minor tweak. Finding a little more room that can just fall into the category of "as much as practical" should be a fairly simple matter.

[eric220]

A little plywood diet later,



I also pushed the start of the helix back about a foot. Got a nice comfortable clearance now.



The clearance point is right above the EMP logos in the center well.

[CodyO]

Looks a little thick on the ply

But good start!

[eric220]

The cap is 3/4", since the helix will be hanging from it. The rest of the turns are 1/2".

[eric220]

Had the Gandy Dancers over again last night. We cut another helix loop.



And began installation of the helix. All six support rods are now in place, including the two that go through the table. The first turn is also now secured to the supports.



On the other side of the room, the tortoises are multiplying under the passenger terminal.

[eric220]

I have been derelict with my updates. A couple of weeks ago, MC Fujuwara stopped by and we went to work on the helix. I didn't intend to enlist him into spinning nuts several feet up threaded rod, but there you have it. We did get several turns of helix installed.



My parents are in town at the moment, and my dad and I put in some time on the helix today. We've got a total of 14.5 vertical inches.



That just leaves one turn. That turn will need to be engineered a bit differently with the transition to the lower level. I can't believe how close the ROW is to the lower level at this point!

[eric220]

I thought everyone might be interested in how the helix levels were constructed, so I photographed the process for the last level.  Here are the cuts laid out on a piece of 1/2" veneered plywood.  (I also lay out the track centers at this point, since the curves share the same center as the cuts.)



First, I use a trammel made out of a piece of masonite,



With a router at the other end,



To make a LOT of sawdust, and incidentally cut all of the curves.



Next, I use a circular saw to cut all of the straight sections.



That leaves the finished part ready to be extracted.



Each level then gets cut in half for installation.  This level only required one cut at the right.

As you might have guessed by now, installation of the helix benchwork is complete.  The last glue is drying, all but two points have been measured and leveled to a nice, constant 2% grade.  The ROW has officially crossed the plains and reached Ohio!



There are still a few wiring issues to resolve, but soon I'll be ready to install track.  This is a major mental roadblock off my mind!

[Scottl]

Nice to see how you do it, and congratulations on passing a major milestone.

[GaryHinshaw]

Looks good Eric.  I am not too far behind you, except I am building upward and laying track as I go, so progress is slower.

Are you concerned about laying smooth track in there, especially along the back side?  It seems a little hard to access.  Did you end up choosing sectional track?

[eric220]

Gary, I did end up deciding on sectional track, as the trial photos a couple of pages back show. My plan is to solder the sectional track together into half-loop sub-assemblies before installation. That way, I only have to make two connections per loop in the helix itself. As the trial photos show, I'm going to use rerailers across the back. They should provide a nice, big surface to apply caulk to as they are installed. That takes care of the furthest back sections, and I should be able to reach most of the rest of each loop. Time will tell.

[Bsklarski]

I used sectional C55 on my HCD. Its so much more smoother than what I can do with flex on smaller radius. Its worth it to me.

[eric220]

On my dad's last day for this vist, we got in a little more work. All of the electrical has been secured or rerouted, and the last of the cork is in, leaving the helix clear for track installation. With that done, we turned our attention down to lower staging. This area has not seen work for a long time, but I felt that it was high time to lay the last track. The spur to "Five Fingers Maintainance" is in.



This section of track is gapped on both tracks, so that I can later install a toggle to switch from track power to programming with center off. It's recessed in a groove so that the railhead is just barely above the tabletop. The plate at the end of the track swivels up and down so that it's not sticking up when the track is not in use. It also provides for the possibility of connecting more track on a temporary cassette. The idea there would be to give guests somewhere to set up their trains that's nice and open and off the mainline.