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Matching Speeds: The HARD WAY

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  • Member since
    July 2006
  • From: North Dakota
  • 9,592 posts
Matching Speeds: The HARD WAY
Posted by BroadwayLion on Sunday, November 25, 2012 3:07 PM

Ok, by now everybody knows the LION will be doing things differently. Him has an automated (analog) layout with many train sets all operating at once. Some of those train sets have two power cars, but there is no problem here since they were purchased at the same time.

BUT many different train sets were purchased at different times and apparently the motors are different from one batch to the other. LION has discovered by trial and error (mostly error) that the slowest units perform best at 11 volts. That means the master control for the whole layout is set at 11 volts. This in turn means that some train sets are running way too fast. LION needs to put a resistor in series with the motor that will give it the exact right speed at 11 volts. It cannot be a wimpy 1 W resistor as that will over heat, fortunately I can buy power resistors for about $4.00 each that will carry 5 W. Nice ... BUT, what value to buy. LION uses 5.1 Ω resistors on his tracks to slow the trains down as they approach the station but this one coasts right on through without stopping.

It will be a matter of trial and error on a test track to discover what Ω value I will need for this train set, and then I will have to test other train sets as I modify them.

Of course the LION being SMART, removed and tossed the circuit boards that came with these cars, maybe one of those had the right resistor on it already. I will paw through that box to see what I can find. The funny thing is it seemed to have a resistor across the motor rather than in series with the motor. What do you suppose that is all about? (Maybe the LION is just misinterpreting the circuit.

This one train (the green one) seems also prone to derailments, so before I search for resistors, I am going to hang some mega weights on the undersides of these cars to see if that helps the tracking and maybe will increase the loads on the motors enough to slow the beast down a bit.

Your Thoughts, Please will be appreciated.

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

  • Member since
    September 2012
  • From: Fraser Valley, BC
  • 538 posts
Posted by Rastafarr on Sunday, November 25, 2012 3:32 PM

Maybe this is a dumb question, but could you add unpowered cars to the train that's running too fast? A little drag should slow things down. 

Stu

Streamlined steam, oh, what a dream!!

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Sunday, November 25, 2012 4:28 PM

 You won;t find 5 watt resistors ont he circuit boards you've taken out.

But you will find diodes. A pair of diodes back to back will drop about .6V to the motor. Unless you never run in reverse, then a single diode would work.

           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    July 2006
  • From: North Dakota
  • 9,592 posts
Posted by BroadwayLion on Sunday, November 25, 2012 4:42 PM

Rastafarr

Maybe this is a dumb question, but could you add unpowered cars to the train that's running too fast? A little drag should slow things down. 

Stu

Well, I added weights (printers slugs, actually, glued to the bottom of the cars), this is helping the tracking but not the speed a whit. These are subway trains, 300' long (6 cars) with 300' platforms (4' long). You could not turn a longer train at the end of the line, the tail tracks are only a little more that 300'. (Scale Numbers, of course!) LION will try the rectifiers, him has lots of those 0.6 v each, eh? The old circuit boards had such diodes, maybe that is what they were for. I am going to bring a wire down under the power cars so that I can try different things without having to take the cars apart every time.

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

  • Member since
    July 2006
  • From: North Dakota
  • 9,592 posts
Posted by BroadwayLion on Sunday, November 25, 2012 4:44 PM

No, there were no power resistors on those circuit boards, and I checked the values of them and they are far too high for my application.

Lion thinks these show promise.

ROAR

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

  • Member since
    February 2002
  • From: Reading, PA
  • 30,002 posts
Posted by rrinker on Sunday, November 25, 2012 5:20 PM

 Give a diode a try. Can;t hurt, plus you should have dozens of free ones left over on all those boards you ripped out. Free is always good.

 In fact, if the faster unit is a newer one that the circuit board was removed from, that's almost exactly it - the gearing may have been changed to account for the fact that it had constant lighting, hence a couple of diode drops reducing the voltage to the motor. No more restriction due to bypassing the board = it runs a lot faster now.

           --Randy

 


Modeling the Reading Railroad in the 1950's

 

Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.

  • Member since
    July 2006
  • From: North Dakota
  • 9,592 posts
Posted by BroadwayLion on Sunday, November 25, 2012 5:49 PM

rrinker

 Give a diode a try. Can;t hurt, plus you should have dozens of free ones left over on all those boards you ripped out. Free is always good.

 In fact, if the faster unit is a newer one that the circuit board was removed from, that's almost exactly it - the gearing may have been changed to account for the fact that it had constant lighting, hence a couple of diode drops reducing the voltage to the motor. No more restriction due to bypassing the board = it runs a lot faster now.

           --Randy

 

Thanks, I will do that, and let you know what happens the next time I go up there.

(You do realize that my layout is three floors up and two buildings over) Laugh

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

  • Member since
    July 2006
  • From: North Dakota
  • 9,592 posts
Posted by BroadwayLion on Monday, November 26, 2012 4:39 PM

Well now, that worked just purrfetcly.

I used four diodes, two in series in each direction which gave me a 1.2 volt reduction which tamed that green train.

Thanks for your help

The Route of the Broadway Lion The Largest Subway Layout in North Dakota.

Here there be cats.                                LIONS with CAMERAS

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