Tehachapi, BC

[ednadolski]

If Danneman was doing this in analog then I can see how maybe it makes sense.

Yes AFAIK he's using DC.   It's just one way to keep the helpers from pushing too hard in case the head end stalls (happens with DCC too).  You want the helpers just to sit and spin without forcing cars off the rails. Seems to me that grade transitions would be the trickiest part.   YMMV, esp. considering all the variables (grades, curvature, train weight, body/truck mounted couplers, ...).

there's a better solution for DCC: control the head end and helpers separately.   If the helpers are pushing too much, notch the throttle down.  If they're pushing too little, notch it up.

Aside from waiting for something to go to the ground, how do you know when (and how much) to adjust the throttle -- just by watching the slack?   What about when the train is in a tunnel or hidden staging?   Also, observing slack in N scale seems hard enough even with MT couplers, but how would that work with the LEZ or TSC couplers that are significantly smaller and have a lot less visible slack?


Ed

[mark dance]

Aside from waiting for something to go to the ground, how do you know when (and how much) to adjust the throttle -- just by watching the slack?   What about when the train is in a tunnel or hidden staging?   Also, observing slack in N scale seems hard enough even with MT couplers, but how would that work with the LEZ or TSC couplers that are significantly smaller and have a lot less visible slack?


Ed

Visual and audible observation and close communication with the head end crew.  These are core issues and they have significant layout design implications...the pusher crew knows their is risk and wants to do well...they know they are responsible for a train going on the ground or not.  On someone else's layout with their equipment, the pusher job first brings stress but then satisfaction when things go well...especially the first few times you do it. 

What I believe you don't want to do is compound this stress to an unsatisfactory level by making trains difficult to observe: too much noise form other crew, inability to follow your train, inability to see your train.  This is one reason why I don't believe hidden cameras are a solution for TBC Bakersfield's hidden staging if independent pushers are used out of hidden staging.   They won't provide the comfort of adequate (complete) observation of the train.  This is behind the suggestion to limit independently controlled pushers to Caliente - Summit even though there is still the single hidden helix turn on this run which needs addressing...perhaps by "daylighting it as much as possible. 

Pushing through a hidden helix is stressful and I believe should be avoided...this being said, Grant Eastman's perfectly speed matched SAR locos pulling/pushing long trains of *very* heavily weighted cars with body mount couplers on tuned, broad curve track had no issue.  (But note that Grant has just had to replace all his worms and worm gear sets due to wear! no such thing as free lunch I guess!)

md

[SAH]

Watching where the slack is taken up and communication with the head end are the keys.  Good running equipment does not hurt either.   For the successful helpers ops I've been involved with the helper goes onto the train at a visible location, the train is visible the entire run, save for short stretches of tunnel (12-18" max) and the helper comes off at a visible location.  The process of cutting in the helpers (important in the caboose era but not so much for modern ops) adds more fun value to the session as the dispatcher must coordinate the helper moves with following / opposing traffic.

[mark dance]

Watching where the slack is taken up and communication with the head end are the keys.  Good running equipment does not hurt either.   For the successful helpers ops I've been involved with the helper goes onto the train at a visible location, the train is visible the entire run, save for short stretches of tunnel (12-18" max) and the helper comes off at a visible location.  The process of cutting in the helpers (important in the caboose era but not so much for modern ops) adds more fun value to the session as the dispatcher must coordinate the helper moves with following / opposing traffic.

ditto on all counts!  I would never have a layout without them now.

md

[jagged ben]

Aside from waiting for something to go to the ground, how do you know when (and how much) to adjust the throttle -- just by watching the slack?   

Yes.  Mostly.  And you learn from running a layout, much like I would suppose the 1:1 guys do.    I tend to know what the train is likely to do when it enters certain spots, and can anticipate what needs to happen.  When I'm on a roll I don't need to check the slack super constantly.   It's more important to constantly check that both ends are moving, and check the slack every 15 or 20 seconds (which is longer than it sounds).   When I start up grade I check the slack a bit more continuously until I'm comfortable I'm in tune with the train's behavior.

The basic method is this: Once you get the train going up a grade and the pushers are pushing the right number of cars, you leave the head end at constant throttle setting and you throttle the rear end up a notch if they are entering a steeper section and down a notch if they are entering a flatter section.  Just pray the dispatcher has cleared you to the top of the grade!   

Going down hill is another post, I think...   

What about when the train is in a tunnel or hidden staging? 

You get used to it, I guess, is what I would say.  See above.  The layout I run on only has three spots where this is an issue and two of them can be viewed fairly easily if necessary, and so I almost always do view the train there when running helpers.  I also only run those spots downhill, for grade reasons.  (The layout can be run as a loop.)  The third one is relatively flat, which helps a bit.  Also, entering a long tunnel can be a leap of faith even without helpers.   

Also, observing slack in N scale seems hard enough even with MT couplers, but how would that work with the LEZ or TSC couplers that are significantly smaller and have a lot less visible slack?

What I would say is: That could perhaps be an issue with those couplers but I haven't done it so I couldn't say.  I suspect that those couplers will still have enough slack to tell what's going on, although any issues of viewing would probably be somewhat exacerbated.  Good speed matching is probably more important. 

Some other general comments:
- Per Mark's comments,  that I'm fairly happy if I'm batting better than .500.      The first run around the layout with a train is likely to have a hiccup or two, hopefully nothing that puts anything on the ground. 
- I've only done this with manifests.  (Not that a unit grain or coal train wouldn't be the same).  I've not done it with trains of 5-unit intermodal sets or 89' flat cars.   I'm not sure I would dare.  You have less slack to work with and also those cars tend to have more tracking issues.
- Our layout has 21" radii in most places.  2.5% grades though.  I don't go up the other way which has +3% grades, I only go down that side.
- Ditto to good running equipment, and clean track.  You can't push the limits on other fronts without those things.
- Doing this is much more like playing a real sport or an intense video game than anything else is in this hobby. 

[GaryHinshaw]

RMMBC 2017

It's been a busy few weeks!  Tehachapi BC was proud to be part of the 2017 Railway Modellers Meet of BC, which is just winding up today.   Friday night featured a 3-layout self-guided tour of pikes on the west side of Vancouver: Mike Culham's Cascadia Railway, Mark Dance's Columbia & Western, and TBC.  I had roughly 40 visitors on Friday night with a peak of about a dozen at one time.  The top construction priority leading up to the event was to make the lift gate at Caliente operable so I didn't have to ask guests to crawl in to see the layout...  Some construction details will follow in a subsequent post.  The highlight of the tour for me was a visit by TRW's Max Magliaro and his lovely wife.  I'm very glad we had some time to chat during his visit, because I was unable to attend most of his clinic on steam locomotive modelling.  (I'm really sorry I had to leave his clinic early, because the first half hour was great.)

Saturday night featured an ops session with 5 guests from BC and Alberta in attendance.  For the most part things went smoothly, though many lessons were learned that will be valuable going forward.  I'll post some details in a subsequent post -- for now here is a quick snapshot from the session showing the crew putting the pike through its paces: just what it is intended for.   

-gfh

[GaryHinshaw]

The last ops session on Apr 22 left me with a set of 3 construction priorities to prepare for this weekend's RMMBC events.  In order, they were:

1. Make the gate at Caliente operable, so that dozens of open house guests wouldn't have to crawl in to see the layout.
2. Power-up Allard siding.
3. Power-up the Tortoises in Bakersfield so the turnouts wouldn't have to be hand-thrown by the host.

Here is the report:

1. I spent last Sunday puzzling over the lift gate, shown here:



The near side already had a piano hinge installed, so that was functional. However, the roadbed on the far side had not yet been cut to allow the gate to swing.  The design problem was how to make sure the track joint (which is on a curve, with a grade, with superelevation...) remains properly aligned as the layout expands and contracts with the seasons.  After much internal kibitzing, I decided to make a channel out of wood that would force both the horizontal and vertical alignment:




The track through Caliente is now permenently glued down.  I'm happy to report that we sent roughly a dozen trains across the gate last night (many with pushers) and had zero incidents with it.  We'll see how it holds up over time...  Meanwhile, guests (and hosts) can once again use the door without crawling:



[Some wiring clean-up still remains.]

2. Allard siding is now powered up, so all segments of the mainline are now in service, save for a few crossovers.

3. 10 of the 16 turnouts in the Bakersfield yard throat are now powered up and operable through Panel Pro.   The remaining 6 will be done soon, but they are not too hard to reach in the interim.

Bakersfield from above:



Bakersfield from below: 



I also spent some time setting up routes on the main jmri panel so that any given track could be lined with a single click:



Unfortunately, Kern Junction (to the left of the yard) is still all hand-thrown.  All good things in all good time...

Thanks for looking.

[Scottl]

That is an impressive set of updates!  I'm glad to hear all went well with the rail meet and open house- I was wishing I was there this weekend (a thought reinforced by snow falling briefly this morning  )

It is quite exciting that the heavy infrastructure lifting is behind you.  The scenery is going to transform the layout.

[GaryHinshaw]

It is quite exciting that the heavy infrastructure lifting is behind you.  The scenery is going to transform the layout.

Well, maybe the heavy infrastructure, but there is plenty of light infrastructure ahead of me still: many turnouts to fabricate and power, many blocks to detect, and a CATS panel to build....  but point well taken.

Here are a few session notes:

* The main "oops" of the night had me puzzled for a while.  A UP stack train was coming out of the Mojave helix to start its run when it stalled and 3 sets of loaded Maxi-IVs string-lined and hit the floor.  Remarkably, the damage was minimal, but the cause was puzzling and the cleanup took a while.  (Trying to do anything with well cars is hard enough -- in a helix it's that much harder.)  The well cars also caused a few cars on a parallel train to slightly derail, which caused them to pick the next set of points and derail further.   The whole Vortex was down for 15 min or so.

The cause was a subtly failing glue joint on an N Scale Kits well set that was causing a well to sag to the point that it hung up on a turnout and stalled.   Kind of a tough thing to catch in advance unless you inspect all cars on a rigorous schedule.

* The highlight of the night was the need for a 3-person crew to help a train up the hill.  We dispatched a manifest train with 2 units up front and one mid-train helper.  Surprisingly, that was not enough, so we added a head-end helper running long hood forward, and the crew capably managed the task from there. 

* Things are now to the point where I really need a full-time dispatcher to manage traffic flow.  The next session is May 30, and I'm going to try and build a CATS CTC panel before that and give it a try.  (At least I now know how to start CATS on my system.)

* There are times when much of the action is on or under the Loop shelf and crowds tend to gather.  As soon as I finish wiring Bakersfield, I can reclaim a fair bit of under-layout storage space and clear out the area around the Loop shelf a bit more.

* For the most part, pusher ops went very well and was a real crowd pleaser.   There is a  bit of a trade-off between how many pushers we run and how many total trains we run, and thus how many (fun) meets we need to plan.  Not sure what is optimal there, but I suspect it will sort itself out in time.  The capped quantity here is humans: we had 6 in the room last night without much difficulty, but one more is probably about the limit.

* I was hoping to have 15 trains staged for the start of the session, but I ran out of tested cars!  I ended up with 11 trains with an average of ~30 cars per train.  We recycled some trains later in the session, and no one seemed to mind.  (It is a frustrating reality in N scale today that few cars can be considered truly "ready to run".  There are so many that come with loose or tight wheels, wonky couplers, etc.... and I didn't have time to test my unopened cars.)

It's all fun though!

[ChrisKLAS]

Your layout is coming along fantastically, Gary! My wiring is fairly neat, too, but yours makes mine look like the proverbial rat's nest!

Re: Pushers (and their power), I've taken a similar, yet different, approach to Mike Danneman. Since about 10% of the Intermountain SD40/45T-2s I've purchased over the years run like absolute crap (or not at all!) right out of the box, I've repurposed those units into dummies and all of my helper sets run with two powered units and one of the dummies sandwiched in between. I only use pushers on trains that won't actually make it up the grade with their assigned head end power. With only two units shoving on the rear of a 45-55 car train up a 2.1% with reverse curves everywhere, even if I stop the head end and run the pushers wide open, the slack only runs in about 15-20 cars, at the most. Certainly not enough force to start pushing the train out of the way and off the rails.

I've actually been very surprised at just how well these little, light N scale models cope with in-train forces. We run a 54 car OGMJC loaded coal drag up the mountain with 4 on the head and one of the 2/1 pusher sets cut in 40 cars back. All 54 cars have truck mounted-couplers (this is the only train that gets pushers which isn't 100% body-mount equipped) and it still performs flawlessly. Of course, you and I are modeling different eras and my helpers still cut out at Summit Sw before everything starts downhill. I'm not sure the truck-mounted couplers would handle things as happily with the whole train headed down into Mojave and the pushers shoving hard on the rear!

BTW, be careful with CATS. It's horribly addictive!

[basementcalling]

The last ops session on Apr 22 left me with a set of 3 construction priorities to prepare for this weekend's RMMBC events.  In order, they were:

1. Make the gate at Caliente operable, so that dozens of open house guests wouldn't have to crawl in to see the layout.
2. Power-up Allard siding.
3. Power-up the Tortoises in Bakersfield so the turnouts wouldn't have to be hand-thrown by the host.




Bakersfield from below: 




Thanks for looking.

That underneath shot gives me the wiring heebee jeebees. 

[3DTrains]

That underneath shot gives me the wiring beebee jeebees. 

Not to mention the heebie-jeebies.

Cheers!
Marc - Riverside

[basementcalling]

Not to mention the heebie-jeebies.

Cheers!
Marc - Riverside

Damn auto-incorrect on my phone strikes again.

[GaryHinshaw]

Your layout is coming along fantastically, Gary! My wiring is fairly neat, too, but yours makes mine look like the proverbial rat's nest!
...
BTW, be careful with CATS. It's horribly addictive!

Thanks for the kind words Chris!  I can't wait to gets CATS fired up. 

Your pusher experience is reassuring.  Additionally, until I have a larger fraction of my car fleet converted to body mounts, I'm finding that I need rear units to help manage slack on the down grades as well.  Otherwise, with all the compression, I find head-end cars with truck mounts can derail on curves or turnouts.

That underneath shot gives me the wiring heebee jeebees. 

The key is to break the job down into simple steps.   

[Philip H]

The key is to break the job down into simple steps.   

Step 1 - get a brain transplant from @GaryHinshaw . . . . .