Too Momentum or Not Too Momentum

Model Railroader General Discussion (Model Railroader)
1

Momentum? Is it a dirty word?

When I first got into the hobby a few years ago, I spent a day at friend’s house who had a very nice set up. He showed me a lot about model railroading and running it realistically. It was on that day, I learned there is more to it, than just running in circles. . All of it an eye opener. Bruce, my good friend now, worked for 32 years for BN then BNSF . And while he hated the real thing, loved the model. But, due to years working the “big Ones” , he uses “real” practices when running his models… How to use the picker to couple and uncouple cars, manual hand throws, operation ideas, good switching practices. But the one thing that got me, and I loved, was his ability to run his engines with realism. Slow in the yard, dont cru***he couplers, spotting at the door, no boomin’ the cut. But the big one? The one that I thought was so cool? He has engines programmed with momentum.

When go my layout up and running, first thing I did with my DCC was program momentum into all the engines. The only engines I have with a lot, are my AC4400 and my SD70. If you have at 50% throttle and cut the power, it will take it 6-8 feet to stop. But then again, it usually carries 20+ cars, figured that would be realistic. The others, on average, at yard speed will take about 4" to 8 inches of distance to stop. I have started that way, and I am used to it. I always get a smile when I hit the power change just right, and the couplers kiss, and start pulling the other way.

But the kicker, some of my friends who come over, have fits! I got engines flying around like torpedo’s, cars getting pushed into bumpers, couplers getting smashed, they are just not used to it… Personally, I dont think a SD7 does start and stop like a hot rod. And neither does a SW7 with 8 cars in line.

I enjoy running them like this, but most people dont, so I was curious… Anyone else run their’s with momentum or am I an odd ball out?

2

I use momentum on my small temporary switching layout, it’s just me that runs trains and I only have 10 programmed in for the CV. I still have to watch them tho, no end stops on the rails!!

Ken.

3

I’ll run with momentum occasionally.

I like using it, but my daughter likes trains close to or at full throttle so trying to stop a train she’s running is important to do so quickly.

Most of the time, I prefer to use the throttle on the power packs. Gradually increase or decrease speed when I have to & using the brakes when stopping.

Gordon

4

For mainline travel I may use momentum (I have DC by the way) occasionally but for the yard im not sure i have the patience, nor do my tracks have the cleanliness necessary for something to run at a slow speed.

5

It is very difficult to hand fly an airplane at 40,000 feet, that’s why there is an auto pilot. For realistic operation, momentum is by far the best method, kind of like an auto pilot, because it is very difficult to do the same thing by hand.

Until everyone can use it properly it will continue to be the issue you discribe, but pratice makes perfect. [:D]

6

I use it all the time.

7

John,

I agree. On the mainline it’s pretty cool However, in the yard - and with my yard switchers in “yard mode” and moving slow - it’s not worth the bother. In those kind of situations, it’s just more practical to perform the momentum myself.

John, when your friends come over to run the layout, make sure you “lay down the law”. It’s YOUR railroad and they are YOUR guests. Every speeding locomotive will be fined $1 and every bumped coupler, 50 cents. Keep the “fine” jar in a convenient spot so that everyone can see it. Repeated offenders will be out of $$$ and a welcome back. That might curtail the delinquents and expedite the “learning curve” to proper layout operation etiquette. Just a suggestion…

Tom

8

John,

Some real railroads have engines setup with a YARD/ROAD switch. This changes how fast the engine ‘loads up’ when you notch out the throttle. When working a yard, you want fast acceleration to ‘kick’ cars down the lead. When on the mainline with a heavy train, you want the engine to ‘load up’ slower so you do not pull a drawbar.
With model railroading, the ‘momentum’ is sort of a double edged sword. Look/feels great when slowing down that heavy train on the mainline, but is not too usefull when switching. Watch a prototype yard job. Lot’s of fast acceleration, and lots of braking action when stopping!

Jim

9

In HO, I hated momentum, the train would seem to react too slowly on my small layouts, even o the mainline. Since I switched to O scale, I have become more of a fan (I use DC) of the pre-set momentum in the DC power supplies that I use (MRC, and an old Troller)
Keeping speeds down is an important issue on my layout, as it is operated by several other people for public displays, and the factory converted 3 to 2 rail locomotives can (and do) move at warp speed! (MTH FP45 and Atlas O SD35) I should re-wire them for parallel (I think, it may be series) to slow them down to the speed range of my old Atlas F9s and Weaver RS-3s/FA-FB-2s.
In all honesty, it depends on the locomotive consist that I am running.

10

Momentum adds the prototype starting and stopping to the hobby. You do have to be careful and give up the typical slot car operation that some use, since the train will not stop unless you hit the panel button.

I requires the operator to think ahead and start the typical stop about forty feet or so before you want to stop.

The Soundtraxx Tsunami requires momemtum to be enabled for some of the features and sounds to work.

11

I do, but my switchers have less than my road engines. A nice feature of Digitrax Series 3 decoders is they have a ‘yard mode’ which cuts top speed and any programmed momentum by half. It’s nice for road switchers, while running on the main you can have the full momentum effects, and then cut it back to switch an industry - a real locomotive pshing only 1 car doesn’t take very long to stop either.

–Randy

12

I’ve been using momentum since the '60s when MR started publishing articles about transistor throttles. Wouldn’t have it any other way.

The last transistor throttle I built had a switch to remove the effect. When I build my next one, that switch will be gone.

My grandkids have learned that trains are not rocket ships and operate accordingly.

Tom

13

I use momentum sometimes. My power-pack has a cool momentum feature built in, so the trains take a little longer to stop than to speed up.[:D] I usually set it to 3, 4 or 5, because that’s where the trains look most realistic speeding up and slowing down.[:D]

14

I don’t use it - my DCC locos are left with the factory momentum which tends to give a delay while speeding up but not while slowing down. I just turn the throttle control slowly reasoning that in the event of a crisis it’s better to stop unprototypically than break something!

15

I too experimented with momentum and at first got a little too carried away on one of my GP38s. The first time I ran it and was getting close to a dead end it was surely heading for the floor had I not hit the panic button. Since then I have only set the minimum amount of momentum on my locomotives.

16

Another tidbit - with QSI-equipped diesels, setting a decent amount of momentum gives you a nice “rev up” effect when starting up - you crank the throttle to where you want it, and the engine cranks up and laods down, gradually settiling down as the loco hits the target speed. Sounds great on the Atlas Trainmaster pulling away with a long cut of cars.

–Randy

17

I love it for road work. My (DC) throttles have a momentum knob with a scale of 0 to 10; I generally have a minimum momentum setting of 3, and notch it up by .5 for each car in the train. I also have braking; once the running speed has been reach, I control the train using the “brake” and “resume” features. My son loves it too, and did even when much younger. The throttles also have an “emergency” brake setting that cuts all power instantaneously.

For switching, I have to admit that I found using the momentum features to be tedious; I simply apply them manually with gradual stops and starts.

18

Interesting topic, question if a person uses momentum on a dc power pack, I assume you are operating with a preset factory settting you can’;t change?

19

They still do that with the Lenz decoders I have fitted to drive the motor nicely, and I discovered they have yard mode as well hit F3 which makes coupling sounds as well as halving the speed at the same time.

Ken.

20

I have no idea about DCC, but I do know that momentum makes a nice, sluggish relistic look as it might look if the engine is under a heavy load. Good luck on getting it sorted out!