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Speed Matching Question.

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  • From: 4610 Metre's North of the Fortyninth on the left coast of Canada
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Speed Matching Question.
Posted by BATMAN on Wednesday, March 24, 2010 6:49 PM

 I have been speed matching two Atlas Trainmasters today.Tongue  Depending on what speed I run them the spread changes 1 to 3 inches over forty feet of travel. Is this acceptable? I hope so as I don't think I can do any better.Cowboy Thanks up front.

 

                                                           Brent

Brent

"All of the world's problems are the result of the difference between how we think and how the world works."

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Posted by Hamltnblue on Wednesday, March 24, 2010 7:47 PM

 I would consider that an excellent match. Place the faster of the 2 in front as your first choice but once they're dragging some freight it will even out anyway.

Springfield PA

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Posted by wholeman on Wednesday, March 24, 2010 9:38 PM

 I would say that your units are matched pretty well.  I have always wondered if they couplers should have slack between the locos or not when in motion.

Will

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Posted by Motley on Thursday, March 25, 2010 12:29 PM
What's the difference between speed matching, and joining the two in a Consist? I thought that the consist would automatically match the two loco speeds? No?

Michael


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Posted by wholeman on Thursday, March 25, 2010 12:50 PM

 

Motley
What's the difference between speed matching, and joining the two in a Consist? I thought that the consist would automatically match the two loco speeds? No?

Consisting the locos basically tells the DCC system to allow the units to run together.  Speed matching is setting the units to run together smoothly.  It's not a "push a button and it's fixed situation".  There are some settings that need to be done to the decoders in order for the units to behave properly.  For example if you run an Atlas unit and an Athearn unit, they will have different speeds and have different start, mid, and max settings.  It also depends on the decoder.  The easiest is to play with the CV values in CVs 2, 5, and 6.  You can program speed tables, but they can be complicating.  You also need to turn of BEMF on the decoders for them to consist smoothly.

Will

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Posted by Hamltnblue on Thursday, March 25, 2010 6:47 PM

 Correct. Speed matching is basically making sure the loco's are very close at each speed step.  One loco at speed step 10 for instance may be moving at 20 scale mph, where another can be at a totally different speed.  This is due to gear ratios, decoders etc.  there are cv settings that allow you to customize them.  When I matched an MTH SD70 to an MTH SD60i I had to use the individual speed steps because the basic setting didn't work.  You test them by running one loco behind the other and increasing a couple of speed steps at a time.  They should stay pretty close together without being coupled.

Springfield PA

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  • From: 4610 Metre's North of the Fortyninth on the left coast of Canada
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Posted by BATMAN on Friday, March 26, 2010 2:57 PM

wholeman

  I have always wondered if they couplers should have slack between the locos or not when in motion.

 

 

Before I spent the time getting them as close as possible I was getting this "slack/no slack" action from the two locos. Every time there's slack that means only one unit is doing the pulling. Before I did the match I was getting a spread of about 18" over the forty feet. Now like I said it is 1" to 3" over forty feet.Thumbs Up

Since I did the matching the difference is really noticeable in how the train performs. It is much smoother now, especially on the flat and level.Smile

As an aside, I was really feeling a bit intimidated at the thought of programing these locos when I got my first DCC unit. But as with everything I do, it's in with both feet. It all gets easy quite quickly. If someone is new and feeling a little uneasy about getting into basic and more advance programing, Just do it and you will open a whole new chapter of enjoyment in this wonderful hobby.Tongue

To the Train Room!

 

                                                              BrentCowboy

Brent

"All of the world's problems are the result of the difference between how we think and how the world works."

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