OK, I know how to speed match 2 engines into a consist.
But, I want to add a 3rd engine. So do I just pick one of the consist engine and speed match the new engine to it. Or do I need to use the pair all ready in the consist and speed match the new engine to the pair?
Pretty sure either way will be fine, just wonder how other folks do it.
Cuda Ken
I run 3 AC4400’s at once… I speed matched the third loco to the first one, (the golden loco) that the second one was already matched too. I run two 4400’s forward at the front and one 4400 at the back in reverse… I learned quickly that the matching has to be precise… My rear loco was a little slower than the front two… Not a big issue until they hit the first corner of my spiral tunnels when the front two were pulling hard and the back one slowed creating a elastic band effect and most of the 30 cars in between derailed and fell onto their sides or on the floor thru the access hole. I only let it happen once and then put up safety railings an nets.
Ken, if you have any two that work well as a unit, MU them, set them running, and then match the third one to the MU’d pair running as a unit.
Crandell
I have had pretty good luck when speed matching. I wonder though, is there a standard as to what is acceptable as far as how close they should be. Like say 1’ difference after a 100’ of travel?
How close do they have to be matched, especially if the engines are going to be in different parts of the train?
Thank you for all the answers folks.
Ken
Some folks use a “golden engine” method. They take an engine that runs really well, and is set up just the way they like it. Then the speed match all their other engines to match that one, and when they buy a new engine, they speed match it to the “golden” engine. That way, all the engines are set to run at the same speed and can all be used together.
You can also do that with different types or “fleets” of engines. For example, I have a nice BLI NW-2 whose top speed (without using any speed CVs) is about 38 scale MPH. I use that as a “golden” engine for my switchers, so I can run any two or more switchers together.
As far as how close they need to be…Before DCC, when speed matching meant adding resistors to slow down one engine to match another’s speed, the rule of thumb was that if they were within about 10% of each other’s speed, that would work. With DCC, I tend to shoot for “as close as possible”, especially if I know two engines are going to work together a lot.
Keep in mind when speed matching a new engine, that as the engine gets some running time, it might run better as it gets broken in, so you may need to go back and tweak the CVs later.
I speed match to the slowest loco of a group of locos that MIGHT run together. For examples, not my Amtrak with my UP GP40-2. I use the stop watch method with about 40’ of track and try to keep them within a couple seconds, maybe as much as 5 seconds.
Richard
Only trouble w/ doing this is that many times you can have a small percentage of “slow” units. I don’t want to slow down almost an entire roster just for a few. This may be acceptable if there are a handful of units that you will usually run together and “slowing” down a couple is fine. Close to 90% of my diesel roster is Kato/ Stewart, Atlas (China not Rocco) and newer 14:1 P2Ks. All these units are quite comparable in speed out of the box. I won’t speed match (slow) 50+ units just to run w/ a handful.
If I do run slower units combined (18:1) P2K SDs I will place them up front and allow the faster one(s) behind. The weight of pulling 20-30 cars slows them and they are close in speed to the slower units. This can be seen as the couplers will “dance” loosely on level track. Only on decending a grade will the faster units want to push the slow engines. Climbing a grade has no effect as the “fast” ones work to pull the train as well, if they slow or underpowered to do the job themselves then the “up front” ones will help out. Not something to do as a regular consist but works.