so I am setting up a new loco and trying to speed match it to another loco that is already matched to several other locos. I am adjusting each step of the 28 speed steps. I want them to run as close together as possible so I am not doing the CV 2,5,6 I am getting to a point though where I am half a number off. if I am working on speed step 1 for example at 6 the new loco runs slower than the older loco and if I bump it up to 7 it runs faster than the old loco. I need to set it to like 6.5 (obviously not possible) so if I run these consisted which would be a better have the faster one push the slower one or have the faster one pull the slower one? basically which loco should I have in front?
I have never done any speed matching so I could be totally out to lunch, but wouldn't it work better if you were using 128 speed steps? That is, assuming speed matching can be done using 128 steps.
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
Check out this thread that I started 7 years ago on this same question.
http://cs.trains.com/mrr/f/11/t/221953.aspx
Rich
Alton Junction
When I run two dissimilar locos together, I always put the faster one in the front. Couplers are meant for pulling trains, not pushing, and they work best that way.
It takes an iron man to play with a toy iron horse.
This would be where a knowledgeable member who knows what part BEMF might play in this matter would jump in. Randy? Anybody?
I think Randy has advocated turning off BEMF for consists, but maybe he or someone else has rethunk it a bit.
wolf10851I am adjusting each step of the 28 speed steps. I want them to run as close together as possible so I am not doing the CV 2,5,6
That could be part of the problem. If you set CV2 and CV 6 to zero and just adjust CV5, and set the decoder to a 'straight line' curve, the decoder will fill in each of the speed steps, probably resulting in a more accurate speed matching than you can get doing each of the 28 steps individually.
wjstix wolf10851 I am adjusting each step of the 28 speed steps. I want them to run as close together as possible so I am not doing the CV 2,5,6 That could be part of the problem. If you set CV2 and CV 6 to zero and just adjust CV5, and set the decoder to a 'straight line' curve, the decoder will fill in each of the speed steps, probably resulting in a more accurate speed matching than you can get doing each of the 28 steps individually.
wolf10851 I am adjusting each step of the 28 speed steps. I want them to run as close together as possible so I am not doing the CV 2,5,6
wolf10851 wjstix wolf10851 I am adjusting each step of the 28 speed steps. I want them to run as close together as possible so I am not doing the CV 2,5,6 That could be part of the problem. If you set CV2 and CV 6 to zero and just adjust CV5, and set the decoder to a 'straight line' curve, the decoder will fill in each of the speed steps, probably resulting in a more accurate speed matching than you can get doing each of the 28 steps individually. If I make 2 and 6 zero which is min and mid then adjust just the high wouldn't that give me where I would have no power at all till half throttle?
If I make 2 and 6 zero which is min and mid then adjust just the high wouldn't that give me where I would have no power at all till half throttle?
Correct. For a straight line, set CV2 to 0, then set CV6 to a value that is half of what you have in CV5.
Mark.
¡ uʍop ǝpısdn sı ǝɹnʇɐuƃıs ʎɯ 'dlǝɥ
hon30critter I have never done any speed matching so I could be totally out to lunch, but wouldn't it work better if you were using 128 speed steps? That is, assuming speed matching can be done using 128 steps. Dave
wolf10851...I am setting up a new loco and trying to speed match it to another loco that is already matched to several other locos. I am adjusting each step of the 28 speed steps. I want them to run as close together as possible...
When DCC came with the speed matching feature, it was supposed to make that easy, but us troglodytes still using DC have learned that if your train requires more than one locomotive to move it successfully, the locomotives will cooperate quite well, regardless of any speed differences, even if their voltage requirements for starting are quite different.There are ways for us to tinker with that starting requirement, but for DCC, it might be useful to adjust that setting rather than the speed. I'd guess that your newer locomotive will then run just fine with the ones already speed-matched. On the other hand, that might not even be required...tie a heavy train onto the two, and see how they do.
Wayne
MisterBeasley When I run two dissimilar locos together, I always put the faster one in the front. Couplers are meant for pulling trains, not pushing, and they work best that way.
I don't think that the order matters. These two locomotives (the lead loco, #34, a brass model with its open-fame motor replaced with a good quality can motor) and the trailing 37, a plastic model from IHC, already with a can motor...
...always ran very well together, but the 37 had a considerable lag in its throttle response. Regardless of the order in which they were coupled, the 34 would respond almost immediately, and would drag or push the 37 for several inches until the throttle setting was providing enough current to get the 37's motor turning. I finally corrected this anomaly by putting a better motor in the 37, and the two now start and stop as one.
OP wrote: "if I run these consisted which would be a better have the faster one push the slower one or have the faster one pull the slower one? basically which loco should I have in front?"
I can't speak for the small ones (I just run single units on my small RR), but on the big engines, you'd want the "best puller" out in front.