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Speed matching locomotives of different brands

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Speed matching locomotives of different brands
Posted by Ringo58 on Monday, January 25, 2021 4:56 PM

I am trying to get my proto 2000 GP38 to play nice with my Genesis GP38. 

The P2K is waaaay slower than the Genesis. Any ideas to fix this?

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Posted by tstage on Monday, January 25, 2021 5:27 PM

Ringo,

It most likely is different gearing between the two locomotives.

You are operating them both using your Power Cab?  Have you tried adjusting CVs 2, 5, and 6 - i.e. Start voltage, Max voltage, and Mid voltage?  Try speedmatching your slower Proto 2000 to the faster Genesis using those three CVs.

Tom

https://tstage9.wixsite.com/nyc-modeling

Time...It marches on...without ever turning around to see if anyone is even keeping in step.

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Posted by rrinker on Tuesday, January 26, 2021 8:03 AM

 I don;t really worry if the model's top speed is lower than the prototype. They didn;t usually rtun flat out, and very few layouts are big enough to runt hem flat out as well. Models always look like they are going too fast anyway.If it can get to 80-90, even if the prototype was geared for 110, that's good enough.

As for the actual question - there are really just 2 things to remember. First is the initial startup speed. You cna only speed up the slower one to match the faster one. With CV2 start speed set to 0 (or 1, some decoders default to 1), that's as slow as that loco is goign to start. If the other loco starts moving much faster, you can increase the value of CV2 on the slower one and speed it up.

Second, for top speed, you can only slow down the faster one. With CV5 top speed unconfigured, however fast the slower loco runs at full throttle is as fast as it will get. You can adjust CV5 of the faster loco to bring it down to the speed of the slower one. There's no way to make the slower one any faster.

Depending on the decoder, you might have CV6 for mid speed, so you cna adjust one or both locos for speed at half throttle.

That's all I've ever had to do, never fooled around with speed tables, if start and max match, then they generally match across the range. Or close enough. Perfect is not required. People coupled multiple diesels together long before DCC came around that allowed us this level of adjustment.

                                       --Randy

 


Modeling the Reading Railroad in the 1950's

 

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

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Posted by wjstix on Tuesday, January 26, 2021 9:02 AM

Once upon a time, out-of-the-box model engines often went very fast. I still have my first MR from 1971 with a review of a new N-scale diesel who's top speed worked out to a scale 220 MPH! Over time, model builders worked to make engines run slower, as generally modellers prefered engines that ran closer to prototype. However some folks who liked to model high-speed passenger trains came to feel the builder went to far, and made their models too slow.  

Stix
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Posted by doctorwayne on Tuesday, January 26, 2021 11:14 AM

Lastspikemike
.... Prototypes were capable of well over the 72 mph scale speed produced by the NWSL gearset. Wikipedia says 85 mph top speed for the RDC...

I can personally attest to the fact that at least some RDCs were easily capable of 90mph, although my timing using a wristwatch vs a conductor's more accurate timepiece may have been a little "off" one way or the other.

Wayne

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Posted by rrinker on Tuesday, January 26, 2021 11:53 AM

200 SMPH was slow for most older N scale locos Laugh

I don;t doubt those RDCs could top out close to 90, you can run those Detoits on the governor all day. They maintanined schedule when they repalces locomotive hauiled trains for the Reading's named trains, Crusader and Wall Street, between Philly and NYC (CNJ terminal and then a ferry across the river). Certainly not those kind of speeds in the city and through the suburban areas to the northeast, but once they cleared there, it's a pretty much straight shot and few if any stops. 

But on a layout - yeah. Even if you have say a 30 foot long section that is just scenery for the train to roll through, if you run flat out close to 90 SMPH, it will most definitely make that 30 feet look like the scale (in HO) 1/2 mile it is. Slw it down a bit and it helpos stretch the space while not looking like it's moving at hand car speed. Half the speed still looks fast, but takes twice as long to cover the distance.

 But to the original subject, if one brand tops out at 50 SMPH, and the other one goes 80, you can't adjust the decoder to make the 50mph one suddenly run 80. You have to slow the 80mph one down to 50. Replace the motors and gears - yeah, then you can make the slow one faster. 

                                                  --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
    April 2020
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Posted by Ringo58 on Tuesday, January 26, 2021 3:32 PM

Thanks for all the tips guys. I will try to get them set up and running together after i get the Switch for DC/DCC wired in. The tips were much appreciated

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