Has anyone here ever tried pusher or helper locos?

[FJ and G]

There's a post on lashing up 2 locos, but sometimes, railroads would put a loco at the trailing end or even in the middle of the train. Of course it was manned during the steam era but in the diesel era, it was more often (but not always), powered remotely from the lead locomotive.

In the post on coupler strength failing, btw, I would suggest using a pusher or helper loco to distribute the pull/push factor more evenly throughout the train.

I'm not sure that this topic of pusher/helpers has ever been brought up, but I believe it to be a viable option

[Anonymous]

Almost all of the modern can motored locomotives can pull 80-100 cars, assuming you could find 80-100 cars with couplers that will stay coupled under this type of strain. Placing another power unit in the middle or at the end of a consist is more likely to cause a derailment especially if the track involves any grades or tight curves. Truck mounted couplers don't have much "slack action" and as soon as they start to bunch up they are going to start twisting the trucks they are attached to. At least on HO and scale O the coupler pockets are on the cars axis and do have some slack capability.

[FJ and G]

Chuck,

SOmeone really serious about doing these sorts of things might consider switching over to Kadees, which also would allow realistic slack

(all sorts of ways to enjoy toy trains)

[KentJJ]

Funny you should bring this up -- just last weekend I experimented with "displaced power" on my TMCC layout.
Since I'm modeling CP Rail routes through British Columbia, I've acquired a few TMCC Dash 9 (AC4400) locos and a fleet of 18 (not 100, but looks like a long train) MTH Coalporter gons with loads. Like the real deal, my replica is also a heavy train. While a single TMCC unit could pull the entire train, a little help from a TMCC second unit couldn't hurt.
Although I configure the two TMCC units as a typical TMCC lash-up, I physically placed the units on opposite ends of the train to replicate prototypical push-pull service. To my surprise, no issues with stretched couplers or accordian effects when the train started, stopped, or rounded my O-72 curves!
My guess is the physics don't weigh as heavily on O guage trains (beefy, oversized couplers; deep wheel flanges; etc.) as they do on the smaller scales. That and the fact the locos I used were identical -- similar models and mechanical performance -- seemed to help matters. TMCC Odyssey sometimes gets a bad wrap, but in this case I think it really helps-- one unit/motor starts to slip, the other compensates appropriately without jamming up the train.
At some point, I may also let two engineers control their locos independently. Most likely, that'll require a whole lot more work than it's worth -- plus I can't think that human operators are able to check the performance of the loco with the same accuracy as TMCC/Odyssey system does.
All in all, the look is very contemporary and it seems to work -- however, I'm not sure my results will be the same using steam locos or trains with non-uniform cars.

[Anonymous]

A matched set of PS-2 units is also likely to have few problems as the speed control plus uniform gear ratio's mean the loco's will just move along together at a constant distance whether there are any cars between at all.

[FJ and G]

Welcome to the forum, Kent [:D]

Your testing certainly sounds encouraging for toy train enthusiasts!

Since I'm using remote control, I'd have to wire up a separate loco or battery car (unless there was a way to carry current thru the couplers and under the chasis (diskised like air hoses) (wheels turning in my head)

[dwiemer]

Kent,
Most of my engines are post war, and I have no TMCC, but reading these posts makes me think of some possible reasons to dive into it. Thanks. PS: Kent, liked the idea in MR about using buildings to hide trackage. Looked cool with the engines being visible in windows.
Dennis

[wrmcclellan]

We have tried independent engineers for helpers on our club layout. This is fun and leads to some interesting wrecks. If the helper is going too slow - the lead engine pulls the cars off to the inside of a long curve since the helper is kind of an anchor.

When a pusher lurches and or pushes too hard, it tends to dump the train - again typically when a curve is involved.

It takes a while to get any good at this.

BTW - most of the RRs call the remote control locos "distributed power" or DP for short. I learned this while doing some radio work a few years back for BNSF and UP. BNSF and UP use DP exclusively for unit coal trains between the Powder River coal fields and power plants in CO and into TX. They were breaking so many couplers that it was the only way to increase train reliability. We passed dozens of these trains while driving back and forth to CO last week. Since we make this drive a couple of times each year - it is interesting to see how long these trains have grown in the last 5 years.

BTW - nice to see Kent posting here - welcome!

[tgovebaker]

Kent, thanks for the interesting post. Quick question: did you set the stalls on the two engines so they were set at equivalent levels?

[ChiefEagles]

KentJJ, tried this on mine with TMCC and Odyssey and I have 72 inch curves [and straights in some of them], still picking up the coal that dumped. I put one of my dummies [that I have put lights and smoke in] on the rear to look right.

[KentJJ]

Quick update -- another thing I tried with my DP (you are correct, Roy - it's "distributed power") consist was to place the second unit mid-train. Nothing wrong with the setup, but just wanted to add on my 19th hopper that includes a working ETD.

Also have to confess that I tried the DP arrangement using two unlike locos (SD90 and a Dash 9). The result of that experiment is the reason I don't have a 20th car in the train [:(] I feel your pain ChiefEagles!

I really think the reason for my recent success with DP is the close operational match I have with my two identical locos -- doesn't always work out that way, but got lucky this time. One other note--I didn't change the stall from the factory setting, but did change the CAB-1 from "M" to "H" to avoid any lightning quick speed transitions.

While manning two powered locos is probably the most realistic, I'd say adding "smart" (TMCC) dummies is the most reliable and affordable approach. I for one can't wait to get my hands on a new Lionel "breakdown" dummy B unit --hopefully they'll be made for modern locos too (SD40-2)!

[winrose46]

In Ogage I have used MTH with the slower engine behind the faster. If you use a mid train engine have the faster engine pulling more weight then the slower one which will ease the speed discrepancy. (All my mth engines are within 1 smph - diesel or steamer) I do have one lashup with the slower engine on the front (Erie Triplex and WM SD40-2) without any issues. On my TMCC lashups I have only been successful with the same engine type (3 RS3 from Kline) I have had no issues whether they are at the front, front and middle, or front middle and end with 18 DC Kline hoppers.

[ChiefEagles]

Kent, I run all of my TMCC engines on H. Wonder if I set the back one up as rear lashup engine???? I had 15 hopper cars full of coal [not plastic] and a caboose. Might tray it again.

[zeames1]

I have done push/pull operation with two Lionel GP-9's w/ Pullmor motors and TMCC around 42" curves on 2.5% grades with no problem what so ever besides an occasional operator error. It makes for an interesting operating step if you run the train with one unit and add the helper unit in at a point before the train takes on the grade.

Jim Z

[Anonymous]

Lionel GP-9' s work well in this configuration because they are light and the wheels will slip. You have to experiment to see if the two or three engines will lash up and run correctly. I have a lionel Sd 70 and a dash 9 that work well together. They move at the same speed and can be used at the ends of a train. the worst problem which can occur with a end lash up is one of the engines hitting a dead spot. When this happens the other live engines will pull cars off the track This is due to the anchor effectof the dead locomotive. In general non tire equipped locomotives give better results because they allow more slippage so matching the two engines is not so important. I have run 3 GP 9#8217; s lashed up together in this configuration one in the front the other in the middle and the last at the end. The only problem is they do not have as much pulling power as a locomotive with traction tires.

[Anonymous]

I only recently worked up the courage to try powered pushers at the end of my consists. I tried it with a pair of Odyssey locomotives (a U30C and a RS11) and failed miserably. I had better success with PS2 locomotives (a Shark AB set and a GP38-2), but I still had occassion derailments on tight curves.

I then purchased a pair of Atlas C424s with factory "EOB" installed. I have never had a derailment with these engines. Amazingly, these engines will even push/pull a consist of 15 Weaver hoppers (with coal loads and original plastic trucks) around a loop with 0-31 curves.

I suspect that a big part of my success with these Atlas engines is the fact that they are mechanically identical. Nonetheless, according to TAS, the "EOB" electronics are designed to compensate for mild to moderate speed variances between locomotives while in a lashup. If this is true, then maybe a lashup of an "EOB" equiped pusher with an Odyssey engine at the point will work (I'll try this tonight).

[FJ and G]

I'm suspecting that in addition to differences in motor speed between units, the other factor that causes derailments are the typical tight curves that slow down the loco traversing them.

Of all of the photos I've ever seen on CTT for the past 5 or 6 years, it is interesting that I've never once seen a pusher or distributed power unit in a freight train.

[Anonymous]

I run all of my trains over 50 cars with a helper of pusher at the end.

[phillyreading]

Have tried it once with post-war locomotives, one engine in the front the other in the rear, mainly I had to retreive a stalled 249E with no access to where it got stuck. The pusher locomotive was set for reverse as post-war and pre-war normally don't have front couplers.
The real railroads use helpers on going up or coming down hills. FEC here in Florida uses up to four SD-40's together at the front of a train, never seen a locomotive in the middle on an FEC run, other railroads yes.
Lee F.