WM Western Lines Engineering Report

[wm3798]

Last night I finished the last little bits of wiring that will allow me to proceed with construction of the yard.  I'll be starting with the east end, toward the engine terminal.

I've also discovered I need to add some stiffeners and maybe a couple more legs under this side of the layout.  I've spent more time than I like clearing cars from staging that have been jostled off the rails.

Lee

[wm3798]

Houston, we have a problem.

After months of successfully running trains through the west staging yard, the last couple of days have presented amazing challenges that are causing me to re-think this whole side of the layout.

Well, at least the bits that are under ground and virtually impossible to reach.

I'm not sure if a heat kink has developed (the layout is in the attic, and it got hot as hell last week), or there's debris that's fallen on the track, or if my haste in laying the recycled c80 flex I used down there is rearing its ugly head...  But it's turning out to definitely NOT be ready for prime time.

It's been exacerbated by the installation of the yard office desk, which makes the distance between the aisle and the exit throat unmanageable without extraordinary effort.


This is the "as built" drawing, and you can see how far back the turnouts are from human contact, and this is made doubly challenging because the vertical clearance is only about 6".


That view pretty much illustrates the problem.

In retrospect, I should have brought the helix around another 1/4 turn, and placed the turnouts closer to the front edge, as I did on the east end in the original construction.



Why I didn't take this into account is beyond me.  And I'm afraid that in the present condition, an easy solution is too.

I'm thinking of dismantling the yard and engine terminal as close to a single chunk as possible, and completely rebuilding the staging loop to a higher standard.  I think I can simply flop the plywood over, and build the "s" needed to get from the helix to the throat.  The throat should end up directly under the front edge of the yard frame seen in the shot above.  Any thoughts?

Lee

[DKS]

OK, take a deep breath. Let's take this in steps.

Are the problems more or less confined to one area, or is it a widespread issue?

If the debris theory is valid, then I'd think a thorough cleaning would be in order, followed by some methodical testing to zero in on the trouble spot(s).

I think a crawler (or something that lets you comfortably lie on your back under the layout) and a mirror might help you inspect things visually that can't be seen from above.

The desk went in last; can it be extricated without causing grave harm to anything else?

Is the yard that's built on top of it structurally integrated with the staging yard's plywood track support? This might offer some insight into options other than just tearing everything apart.

In retrospect, I should have brought the helix around another 1/4 turn, and placed the turnouts closer to the front edge, as I did on the east end in the original construction.

Hindsight is always perfect. I think I'd have reversed the direction of the helix, so it enters and exits at the front.

[davefoxx]

Yeah, I'm with DKS.  Let's slow down and diagnose the problem.  Sure, it would have been better to bring the turnouts up front, but that might turn out to be a non-issue.  Get back in there and clean out the funk.  Could be as simple as a piece of sawdust from construction is between the rails or shoving the desk in there killed clearance for the trains.  I don't think that you should consider tearing that section out until it turns out there is no other solution.  Hopefully, worst case scenario is just replacing a piece of track that's gone bad.  I say leave the yard alone and just correct the problem that is causing derailments.

[wm3798]

Yes, the desk can be structurally removed without major incident.  The only issue there is the cabling to the little control box, which was already cut and reinstalled once, so I can manage doing it again.  If it ends up getting moved again, I'm thinking it will be wise to install a multi pin plug, like a video monitor cable, so it can be more easily unplugged in the future.

No, I have not done a thorough inspection or run multiple tests with an engine or two, but I have tried to run a couple of trains through, and the problems became apparent that way.  I will be doing that at some point in the near future.

Regarding working below the yard area, I think I can manage that with minimal disruption to what's there.  One trick I can pull would be to temporarily suspend the front edge of the yard from the new light valance:


I can use some temporary legs to prop up the back while I work my way down to pull out the staging loop.  Now that I'm thinking of it, when the staging loop is out for revision, that would be an ideal time to build the yard and get it wired from below, since it will be unobstructed.  I can then reconstruct the staging loop to a higher degree of quality and reliability, then slide it back underneath, connect the tracks at the base of the helix, and it's off to the races...

As for timing, I will try to get at least two of the tracks functional in their current location for the purpose of our planned session at the end of June, then when my wife goes to Florida in July with her girl scout troop, I'll make use of the time by doing the major structural work that will be needed.

It can be done.  The east staging yard works very well because when I originally built it, I took my time to make sure everything was solid.  When I rebuilt that, I was able to reconstruct the inbound throat with long switches, because it was accessible from the aisle.  The west end was not as well thought out, nor as methodically constructed, and the simple fact is that I am now paying the price for those oversights.

Lee

[wm3798]

That's what I should have done in the first place...  Now to plot out how to make it happen.

Lee

[DKS]

Could you do a twist and turn, instead of a overhaul and flip? Just hack out the throat, pivot the whole shebang forward, and craft a new throat?

[davefoxx]

Could you do a twist and turn, instead of a overhaul and flip? Just hack out the throat, pivot the whole shebang forward, and craft a new throat?

This actually an ingenious idea, if it comes to redesigning the west end.  The problem will be getting to all of the screws holding that yard down to the benchwork.  A right-angle drill with screw bit would be indispensable.  If I remember correctly, though, the track was put down before the yard was installed, so the screws should all be exposed and not buried under track and cork.

DFF

[wm3798]

Here's the rub.  When I laid the track down under, I used hot glue, which has turned out to be inadequate on many levels.  Over time, it lets go of the plastic ties, And during installation, it dries so quickly the it created a few lumps that may be contributing to the problems I'm having now.

I also used a lot of well -worn salvaged track, and since then, I've gotten some much better quality new track that can replace the worst of the worst.

If I'm going to extend the efforts to fix the accessibility, I might as well go the distance and reinstall the track properly.
Lee

[DKS]

Yikes. Three steps forward, two point nine back.

Hope you didn't assemble the helix that way...

...and if you did, is that at risk of possible failure, too?

May I suggest, if it is, then go the whole nine yards and reverse it. That would make life much easier on many levels (pun intended).

[DKS]

Here is some accurate geometry for your consideration. Hope you have lots of left-hand switches...
 


Larger: http://whiteriverandnorthern.net/images/west_staging_1.gif

[wm3798]

No the helix is the standard c-55 over cork installed with yellow carpenter's glue, just like most of the rest of the layout.  The staging loop was the only hot glue experiment, probably because I didn't have $3 to get a bottle of yellow glue

The max width of the return loop will be the same 36".  You've got 48" there.  Also, I eliminated the crossover after the helix because it made the reverse circuit too short for the typical lashup.  Left hand switches shouldn't be a problem.

I shall head up to the lab shortly to see if the stopgap repairs I made last night have held.
Lee

[DKS]

The max width of the return loop will be the same 36".  You've got 48" there.

Sorry, I was trying to follow your rough draft, and was having a bit of trouble. Will revise.

Update: Refresh the page, image has been replaced.

[wm3798]

While you're up... note that the lowest level of the helix extends beyond the 32" radius loop.


Not by much, maybe 3".  Hopefully this fact will help make the modification go a little more smoothly.

For ease of construction, the transition would begin at the end of the plywood there on the bottom rung.

Lee

[DKS]

While you're up... note that the lowest level of the helix extends beyond the 32" radius loop.

Always a surprise lurking somewhere.

For ease of construction, the transition would begin at the end of the plywood there on the bottom rung.

May ease construction, but sure won't ease that S-turn...

Hey, ho...