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Hi,

I am wanting to set up speed tables for a number of locos and am wondering whether anyone has (or knows of) a list of settings they have used succesfully for different classes of locomotive

eg - Rebuilt West Country, Rebuilt Merchant Navy, King Arthur, M7
Black 5,

Alternatively has anyone any suggestions as to the equivalent "speed in m.p.h." for given settings/power output.

i.e. 255 is maximum power available, but what settings are equivalent to
speeds of 100 m.p.h, 90 m.p.h, 75 m.p.h. etc.

Or do I assume that for an express passenger locomotive a setting of 210 is equivalent to 125 m.p.h. and work backwards.

Regards

Ian 47

Ps - I will probably post this enquiry on some other DCC forums
 

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QUOTE (Ian 47 @ 20 Oct 2008, 20:42) <{POST_SNAPBACK}>Hi,

I am wanting to set up speed tables for a number of locos and am wondering whether anyone has (or knows of) a list of settings they have used succesfully for different classes of locomotive

eg - Rebuilt West Country, Rebuilt Merchant Navy, King Arthur, M7
Black 5,

Alternatively has anyone any suggestions as to the equivalent "speed in m.p.h." for given settings/power output.

i.e. 255 is maximum power available, but what settings are equivalent to
speeds of 100 m.p.h, 90 m.p.h, 75 m.p.h. etc.

Or do I assume that for an express passenger locomotive a setting of 210 is equivalent to 125 m.p.h. and work backwards.

Regards

Ian 47

Ps - I will probably post this enquiry on some other DCC forums

After 30+ yrs in this hobby I have yet to find two , or more, locos that run exactly the same.
The speed table for one loco will not necessarily match another loco.
To get the speed settings equivalent to 100mph,90mph, 75mph etc., is trial and error.
To set top speed I use an electronic speed trap but if not available, use a stop watch ( most wrist watches have them) and time loco over a set distance. There is a speed calculator on the net, google speed calculator ho/oo scale. EG 60mph in HO/00 is one foot per second.
I set CV94 to desired speed, CV67 so loco is just moving then average the difference between CVs94 & 67 and setCVs 68-93 accordingly. Set one loco then match other locos to it.
Before starting set CV3&4 to zero and speed steps to 28. These CV's are set once speed table is done.

Hope this helps a bit.

Ian
 

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I avoid working on the speed table itself if I have access to max (CV 5) and mid (CV 6). The easiest way to set the speed table is by using a programmer or computer interface. The Flying Scotsman (see review) was set as follows:



But this all depends on how you determine top speed and the shape of the speed curve.

If you see some of my earlier reviews in the Reviews section, you'll see that I did apply some logic to this issue.

This is the speed table that I set up for the 'Bibby Line' Merchant Navy:



I figured that the loco would go fast, but not the top speed which was reserved for a modern loco or high speed A4.

So since then, I set large locos to about 180 to 200 and smaller locos to about 100. I adjust acceleration, deceleration and midpoints accordingly to give good running as realistic as possible, but without getting too pedantic about it all.

For the Class 09 'Dick Hardy' (see review), we did a speed test and scaled it to the 27.5mph max speed of the real thing. It seemed fine with the following speed table:



For this loco though as with other similar shunters, slow running is more important that top speeds, but the setting of 100 as the max was about right. Generally the default shape of the speed curve will be fine once this top speed is set. You're not going top really notice much of a change if you tweak it slightly.
 

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QUOTE (Ian 47 @ 20 Oct 2008, 19:42) <{POST_SNAPBACK}>Alternatively has anyone any suggestions as to the equivalent "speed in m.p.h." for given settings/power output.

i.e. 255 is maximum power available, but what settings are equivalent to
speeds of 100 m.p.h, 90 m.p.h, 75 m.p.h. etc.
There is no correspondence between a decoders speed table and the absolute scale speed of the loco since there are too many factors (motor characteristics, gearing, wheel diameter) that are unknown to the decoder. All you can do is experiment by trial and error.

Andrew
 
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