Northern Tablelands Express approaching Ardglen Tunnel

Northern Tablelands Express approaching Ardglen Tunnel
Click on the above photo to see the Main North Album at Flickr

Wednesday, July 28, 2010

30 MPH Max Speed "Matching" of ALL my Locos.

On my trip to U.S. in July 2011, where I saw about 20 "high tech" mostly DCC layouts and many home and exhibition layouts here in Sydney, I’ve observed that 99% of trains are run at speeds below 30 MPH. I wonder how many model railroaders operate their locos at their maximum prototype speeds.

My double deck “Main North” is located in a 30’ X 30’ area (approx). There are no long straight runs and many of the curves are 24 inch radius. This means operating at near prototype maximum speeds is impossible. Many trains require require double heading of locos. Rear end "banking" is necessary on the 60 foot climb to Ardglen and both operators need to run the two locos at approximately 10 MPH., "Speed Matching" of locos will help my Operators keep the locos/trains on the track and off the cement floor 5 feet (1500mm) below.

I have restricted (Speed Matched) the TOP speed of all of my locos to 30 MPH and this provides:

1. What I consider a better "finer" control of your locos. Full range of your locos (0 to 100%) is now 0 to 30 instead of 0 to 70 etc, where in most cases you only used "half" the range of the Throttle.

2. ALL locos, speed wise, operate the same making Banking or Double Heading, easier.

3. Adjusting your Speed Table or CVs 2, 5 and 6 to provide a LINEAR response, the display on my Procab now indicates the approximate Miles per Hour. That is at Speed Step 20 the loco is travelling at approximately 20 MPH as shown etc.

I have made a Speedo Car that makes Speed Matching your locos even easier, For my latest description on how to make a Speedo Car, see my Speedo Car Blog entry.

Without a Speedo Car, measuring the speed, nothing too technical - 36 inches of straight track, a Stopwatch and a Calculator like this one at:
For 36" length of track - 10 Scale MPH takes 18 seconds and 30 Scale MPH takes 6 seconds.

Adjusting the decoder’s CV 5 will provide “close enough” speed matching. You may also need to adjust CV 6 to "half of" CV 5's value to make the speed curve" "linear". When reducing CV 5 and 6, the loco's "take off" may be affected so CV 2 may need re-adjusting to get a smooth jerk free take off.

Some decoders like my Soundtraxx DSD and Tsunamis do NOT support CV 5 and 6, see your applicable Manual. For theses I reduce the Top Speed by two methods:

1. Selecting a Speed Table in CV 25 and programming CV 66 (Forward) and CV 95 (Reverse), to less than 128 – lower the value, the slower the speed. See Tsunami Manual.
2. Selecting the “User Defined Speed Table” (CV 25 to 16) and making a Speed Table.

As with all my programming, I use Programming On the Main - POM. This method gives instant results  "out on the track" eliminating the necessity of returning to the Program Track, that's necessary when Speed Matching locos. NOTE: Contrary to what you may read on the Internet, using POM correctly no OTHER loco will be programmed. Just follow your Throttle "prompts", reading them all and go slowly.

For all of my programming, I use Decoder Pro downloaded free from the Internet and loaded into my Laptop that's connected to my NCE DCC system with the applicable Cable/Adapter. See the bottom of this page for the link for more details.

  1. Make a Decoder Definition if you don't already have one, for your desired loco.
  2. Select Speed Table Tab.
  3. TICK the "Use Speed Table".
  4. In the "Speed Table Selection" select "User Defined Speed Table".
  5. Place the cursor on the Slider for Speed Step 28 (CV 94) and drag down the Slider to about midway (120).
  6. Then select the "Match Ends" tab under the Table. This will adjust all the intermediate CVs to make a linear line "speed curve".
  7. Select the "Write Changes" Tab.
  8. Decoder Pro will program the appropriate CVs.
  9. Operate the loco at MAXIMUM Speed. For me this is Speed Step 28 when using 28 Speed Steps - NOT 28 out of 128.
  10. Repeat the above Steps 5 to 9 until the Speedo Car displays 30 MPH or your desired Top Speed. Without the Speedo Car, use the Stopwatch and Calculator from above. Note: For HO, the loco should take 6 seconds to travel the 36 inches for 30 MPHs etc.

Do this procedure to ALL of your locos and they’ll all run the same – speed wise, making double heading and banking, easier.

Fine Tuning the Soundtraxx Tsunamis

Tsunamis “out of the box” provide a too high slow speed and a noticeable jerk between the lower Speed Steps, when using 28 Speed Step Mode. Operation is better with 128 Speed Steps.
My Tsunami adjustments are based on what Bruce at Litchfield Station posted some years ago and a long discussion on Back EMF on the Soundtraxx Yahoo group during June/July2010.

For my above Max 30 MPH Speed Table, I need to use the 28 Speed Step Mode, I’ve fine tuned my Tsunami equipped locos for 1- 2 MPH speed at Speed Step 1 and smooth jerk free acceleration by adjusting a few of the motor performance CVs, using Bruce's following procedure:

  1. Program both CV 3 and 4 (Momentum), to “0"
  2. Program CV 209 to “10”
  3. Progressively increase CV 210, starting with “1”, until the loco moves, at Speed Step 1, albeit a little jerky.
  4. Program CV 209 increasing by 5 until the loco is smooths out.

Reducing CV 212 (default 255), will further slow down the loco.
Using 28 Speed Step mode with the Maximum Speed reduced to a 30 MPH, the voltage increment between Speed Steps is about 1/3 of the default Linear Table, so the jerkiness between Speed Steps has been all but eliminated.

Steam Chuff Rate or Diesel Notching Speed Steps, may need to be adjusted if you use the 30 MPH Max Speed Table. If this is a Diesel loco, then CV 116 would have been programmed to maybe “46” so the engine “Notches up every 14 Speed Steps”. Re-program CV 116 to “7” or “39”. For Steam, re-program CV 116 to “80” and then test for 4 Cuffs per wheel revolution at 10 MPH. May be time to use the Tsunami Manual or go on line to Soundtraxx at:

When finished with adjusting the Tsunami, adjust CV 3 and 4 (Momentum) to your desired values.

If you have not used Decoder Pro for programming decoders, for details and what’s necessary, see:

Thursday, March 18, 2010

Murrurundi on the Main North

Adding "operations" like "banking" and "double heading" was one of the main reasons for choosing the "Main North" section of the NSWGR in the mid 60s.

Murrurundi on the southern side of the Liverpool Ranges during the 60s, had a delapidated Loco Shed and a 60' Turntable. "Down" trains required assistance up the 1 in 40 climb to Ardglen at the summit of the Liverpool Ranges as these train headed north to Werris Creek and beyond.

Discussion with one of my modeller mates Brian, about Murrurundi and some photos being exchanged, prior to his visit to Sydney in March 2010, provided me with a pleasant surprise when he turned up. He bought me a model of the delapidated Shed. Now I had to tidy up my Murrurundi that required some major re-building of the baseboard and pinching some of Newcastle (see layout plan) to fit in the re-located Turntable.

For once in my life I bought something for my layout that actually got installed within a few days - a 60' motorised Turntable with 30 degree mechanical indexing. Just what I needed for Murrurundi now that the Shed was closest to the front facia, making the only location for the Turtable, behind the Shed. To turn the loco it takes 45 seconds. I'm impressed with the Frateschi $150 Turntable from Casula. I'll need another one at Willow Tree.

The photo shows 3666 having a drink from the Parachute Water Crane. A second operator reversing 5259 out of the Shed, to perform one of it's "banker" duties for the day. A green 3635 is waiting it's turn in the Shed, while 3230 has been turned and is being serviced. A Coal Grab will be added here, soon.

With 5259 attached to the rear, both operators will drive the train "up to" Ardglen, some 40' on my layout up the grade, taking about 10 minutes at 10 MPHs. At Ardglen the "banker" (2nd operator), "disconnects and reurns 5259 to Murrurundi. Depending on operational requirements, the banker may go through to Willow Tree, where banking is required for UP Goods trains.

With Murrurundi Loco now operational, it is going to be busy here, as all trains including the Northern Tablelands Express (double headed), needed assistance going over the 'Range. Slow steam hauled Goods trains, due to the fumes and heat build up in the narrow small bore 1600 metre Ardglen Tunnel, could not be double headed, they had to be banked from the rear. I'm glad as this "banking" as it creates extra fun for us, as we operate the Main North.

So Muururundi has been partially scenicked with these "structures", but so much more to add, next a scratchbuilt Station. My excitment at having something looking a little bit like the real thing, needed me to share it with you.

Thanks a lot Brian for getting me going with the Murrurundi Shed.

Tuesday, March 2, 2010

Too much to do to update the Main North Blog

It's nearly a year since I created my Main North (mainnorth) Blog. Too much to do, installing sound decoders for others, repairs and upgrades to NCE equipment including upgrades to NCE radio (RB02 & throttles), working on the layout and actually some running of trains, to update this blog. Since I found there are a few of you watching after I visited Ray's blog, I thought I should update you with some of the progress I made in the last few months. First I had to re-new my password (forgot since it's been so long), any of you old fogies out there having the same problem. I fear going out these days as I might forget my address.

Before Christmas, I moved Sydney Staging from under Newcastle to underneath Broadmeadow Yard and included a 22 inch radius return loop. I've been able to include 4 "through" staging tracks under Broadmeadow, the longest 2900 mm, to stage my W44 Concentrate Train with a Garratt & C35.

Having a Return Loop has created a much longer "run" for each operator now. For example for the Newcastle Flyer that's staged at Newcastle, it would be run just to Sydney and "terminate". I'd have turn the loco. Now run the Flyer to Sydney then through the Return Loop and back to Newcastle, where each operator would light engine the C38 to Broadmeadow Yard, service the loco, turn it and L/E back to Newcastle, ready for the next time the Flyer needs to be run. Similar for the Northern Tablelands Express, staged at Werris Creek Station. To Sydney and now back to Werris Creek where the C36 would be turned and the van repositioned at the rear of the train.

In Febuary I modified Suphide Junction but only after I had re-read Byways of Steam 22 and realised there was something wrong with the text and what is in the track diagram, it said "Upon arrival at Sulphide Junction the ore train would cross over to the yard on the Up side of the main lines, then push back into the exchange sidings". Trouble there are was not a crossover to do this. Researched further and secured a copy of July 85 Roundhouse and found a different story. On arriving at Sulphide Junction, the wagons were propelled via a crossover to Exchange Sidings. How was I going to do this, the locos would be in the next room through Tickhole Tunnel and across the brige into Broadmeadow Yard, if I was to copy this movement. I decided to install the "crossover" in reverse and do what the Byways article suggested. When building a layout, you have only so much space and many compromises have to be made. This is one.

For an interum, I made a rough cardboard Sulphide Corporation Smelters Works, so I had somewhere to shunt to and pull out of, for the W44 and Superphosphate S wagon train. Hopefully some time in the near future I can find some time to make a better Sulphide Works, but this will do for now.

I have edited my Cards to be more specific so visitors can understand what they have to do. I'll add some maps etc, but Operating Sessions with my Card system is so much fun. To operate the Double Garratt loaded Coal train from Newstan Mine to Port Waratah, tgen back via a "sneak path" to Newstan Mine and all the BCHs marshalled under the Loading Bin, takes 45 minutes.

In the photo of Sydney Staging (right), a Sydney Fast Electric Parcel Van is getting a "road test" after installing a QSI Revolution sound decooder loaded with a U.S. GG Electric prime mover and a 620 Horn and a NSW Guard's Whistle. I've always wanted to have a Red Rattler 4 car set and now that I have "road tested" a Van, I'm investigating whether this and the 4 car set can "run" on the Main North. They could operate to the end of the photo, where I could make a "Cowan", but this could not justify purchasing them, for this short "run". Maybe a run down the Cowan Bank and into Gosford and back, may be the only "non" prototypical running on the Main North. With at least four 46s operating all trains from Gosford up the Cowan Bank, when Auscision Models release them, the Red Rattlers won't look out of place. What do you think?