Model Trains

[andy3055]

Thanks for the info. I thought DCC ready was the standard now. Not every one wants DCC already configured. People want different configurations.

[MarkF]

Earlier in this topic, I posted a graph of my updated speed profile and a photo of the stack of circuit boards.  Here is the schematic of how the speed profile is delivered to each track section.  And the emitter follower transistors on the track power board to provide the necessary current to the track.  The track power PCB also performs current limiting and locomotive occupancy detection.  Shown is one of ten PICs used to generate the profile (PWM for slow speed or DC for medium to high speeds).  The track is powered from a 15VDC power supply in order to have enough headroom for the op-amps and the power transistors to provide 12V to the track.

Each logic PCB has five PICs to generate the speed profile for ten track sections/blocks.  And there is a track power PCB for each track section.  Currently I have 2 logic boards and 15 track power boards.  Additionally, there is a PCB capable of driving 30 relays for turnouts and LED lights.

[MarkF]

Farm update.
I thought I would only have space for the barn.
Now I have five buildings. 
Barn, milk house, main house, out house, and wood shed.

[andy3055]

Very beautiful! Once you do the trees, grass, etc., it will look great. I am waiting to see what you will come up with.

[andy3055]

I have installed a LocoFi™ system on my Hornby Class 37 locomotive. It is part of the Hornby Freightmaster set which I bought many moons (some 40+ years) back! It has a 3 pole motor due to which the speed control is lacking very fine control. I have to increase the track voltage to get better low speed control. LocoFi™ can handle p to some 20+ volts. I still think even with a 3 pole motor, I should be able to fine tune it with the acceleration controls.

[MarkF]

I did a quick look at LocoFi and you should be able to adjust it's speed profile for better performance.  It appears to have limited adjustment capability but you might try lower it's max speed to start.  That would shift the profile points to the lower end giving you more control.

It's hard to tell from the video but it looked like the locomotive was running very fast at 1/2 or less speed setting.  If that was the speed you had with the controller set near its max, you would have better control.  I'm not big on seeing trains zooming around the track at 200mph scale speeds.  And my new locomotives don't run as fast as my older 80s era ones.  Most of the old locomotives run much much faster than their prototypical speeds. 

You are correct in that you should be able to adjust the LocoFi to give better performance even for your old locomotives.  (My post with the speed profile graphs was to get that performance.)  I am able to have my old locomotives barely moving while still pulling 10 or more cars.  I can watch a locomotive slowly move from tie to tie.  You just need to push the settings toward the low speed end.

You won't be able to duplicate this with LocoFi but this video may give you some ideas on how to configure what you have:
   


A quick update:
Looking at the LocoFi Locomotive Configuration pdf, the default number of throttle notches is 8.  I use 50 and DCC defaults to 128.  Push that default up to 32 or 64 notches for finer control.

[andy3055]

Thanks, Mark. You are correct. One problem I notices was that at 12 Volts (DC) track voltage, I could not get it to move until the speed control was around 25 MPH. However, when I changed it to a pack with 16 Volts, I got better slow speed control. Now I can get it to move around 15-18 MPH on the control. My thought was that the "old" 3 pole motor did not have enough torque to get it moving. I did not want the track to be too high as I want to be able to run other locos without burning the motors going over 12 Volts.

So now, I must play with the settings as you mentioned to get better slow speed control. Yes, I too like things to move slow so that it looks more realistic. I think I have a lot more to experiment with this contraption. Thanks again for the pointers. Much appreciated.

[MarkF]

Take a look at this video I found on the LocoFi website under the LEARN tab:

It's about consisting two locomotives, but half way into the video he shows how to adjust the speed and the resulting slow speed performance obtained.  I believe your setting the voltage higher is just treating a symptom and not the cure.  The very first thing in the calibration process was setting the minimum to get the locomotive to move.  DCC is 14V so you might want to do you setup with 14V so you could run it on someone elses layout.  Plus 14V gives the module some headroom to provide 12V to the loco at max speed.

I use 15V on my layout because that is the next most common off-the-shelf fixed DC power supply voltage above 12V you can buy.  And +/-15V was the typical op-amp voltage back in the day.

 


Update:  Fixed bad video link

[MarkF]

My thought was that the "old" 3 pole motor did not have enough torque to get it moving. I did not want the track to be too high as I want to be able to run other locos without burning the motors going over 12 Volts.

You're on the right track.
The problem with the old 3-pole motors is that it takes a lot to overcome friction in the rotor.  All of the new throttles and DCC use some form of PWM to get them going (in addition to the new motor designs).  The latest DCC modules are starting to use EMF feedback to track the motor response.  Providing a firm lock on the motor RPM.  You just need to tweek the parameters to get the desired response.  Before PWM, throttles experimented with rectified AC voltage to create a small vibration to over come the friction.

I see your point wanting to staying with 12V for track power since you're also using non-modified locomotives.  I don't see a problem with this for LocoFi.  Your LocoFi equipped loco will just have a slower top speed.  I doubt you will even notice unless you're having a race.  Just use 12V for your setup and see what king of results you can obtain.

Like I said, I use 15V for my supply but my track will NEVER see that voltage.  My high current driver boards will drop at least 1.4V of the that.  Plus more voltage loss due to the voltage gain setting for my op-amps.  I seem to remember the highest I can drive my track was 12.5V from direct measurement at the rails.

[andy3055]

Thanks, Mark. I need to understand more about the different adjustments and how they contribute to this. As for the 16 volt issue,  I have to keep it in mind when changing to the DC only locos. Nothing like trying the various tweaks.

[andy3055]

At last!

[MarkF]

Looks good.
Do I detect that there was a little hair pulling involved?

Are you going to upgrade your other locomotives now?

I was looking at the Roco Z21 system earlier today.  It's similarly based on an app and WIFI.  But it uses the standard DCC decoders in the locos instead of a propitiatory decoder like your system.  Model railroad electronics is growing by leaps and bounds it seems.

[andy3055]

Hi Mark,
Actually,  I didn't understand the terms and what the various adjustments did until I saw a clip they sent me where someone else explained in detail how to set up things. The info given on the enclosed paperwork did not do a great job. Once I watched the clip, I was able to get it right off. Probably also because I never tried any other things like DCC, may have contributed to the problem I had.
As for other locos. I want to do one more for the time being. Can't afford a lot when retired and on SS and a bit of savings!
You are correct in that many systems are now being developed.  One example is using a basic Audrino to do speed control.

[MarkF]

I mocked up an abandoned railroad tunnel at the end of one of the depot sidings where it's too close to the mountain in the corner.  Used an old rock tunnel portal and a wooden retaining wall section I didn't use.  The hill will be a combination of rock carving and retaining wall along the track.

What's everyone think?  Keep the abandoned tunnel or loose it?




In addition, I just finished printing an extended passenger platform (part with green roof).
Like they say: "If you build it, they will come." 
People are still in their shipping bag.
The bench seating and the lighting doesn't show up in the photo very well.


For the big picture, I updated some of my photos on the first page of this topic.

[andy3055]

I likw the platform. It looks very neat. If i were you, I would keep the tunnel. It makes for a part of the train get hidden when moving. Once you do the landscape detials it will look nice.

BTW, I got my 2nd LocoFi unit and have two locos now with them It is much better than having just one. I have met the guy who does it in person. He lives in San Ramon which is just 20 minutes away from me. Nice guy and very helpful and responsive as well.

[MarkF]

BTW, I got my 2nd LocoFi unit and have two locos now with them It is much better than having just one. I have met the guy who does it in person. He lives in San Ramon which is just 20 minutes away from me. Nice guy and very helpful and responsive as well.

Nice.


I've been doing some serious mods to my software in the laptop.  I'm doing a little 'assisted automation' where the power to each block follows the locomotive and the direction of each turnout.  Giving it a little more DCC feel for control.  Currently, I'm limited to two loops (i.e. the inner one and the outer one) without the ability to cross between them.  It uses up two of the slots allocated for pre-programmed routes.  You can still get down to controlling each individual track block and turnout from the wireless throttle.

Just started testing and nothing has blown-up yet....      ya!
I'm quickly finding out that my blocks are too big which limits my sensing the loco positions.  And it would be nice to be able to sense the position of the end of each train.

My biggest worry and issue is when a loco stops on top of two blocks.  If the two blocks are of opposite polarity, they will short out.  I have current limiting in each block but was over generous with the max needed for a train.  I was thinking the old locos would pull close to 1A and a consist of two would be 1.5A to 2A.  Each block is limited to 2.5A at this time which is far too high and the heatsinks overheat.  I'm running two consists of two locos each (i.e. 4 locos) at one time and they only pull 0.75A total.  I bought new sense resistors to reduce the limit to 1.5A but haven't had the motivation to crawl under the layout and change all 15 of them.  Soldering over ones head is not fun.

[andy3055]

What is the reason for you to have different polarities on two adjacent blocks?

[MarkF]

Here is the track plan divided into its different blocks.
(Some track is not shown due to the limitations of the free version of the AnyRail program.)



Mistakes happen.  I first discovered how big the problem is while running multiple locos.  I left one sitting on top of two blocks while trying to run a second loco onto a section so the two could pass in the opposite direction.  While moving the second loco, I noticed it couldn't get it to run very fast even at high throttle levels.  It turned out that the slow block was being shorted out because the first loco was between it and an adjacent block that was turned off but in the opposite polarity (direction).  This occurred while two locos traversing the wye.

A turnout in the wrong direction can route a loco into a block you're not expecting to use.  And you don't know what polarity it was last left in.  In most cases a shorted block wouldn't last long.  But, you may not realize what is going on for a while.

I've since paint a tie blue where the insulators are between blocks to help damark their locations.

[andy3055]

Ah! Got it. True, it is hard to remember where the insulators are. Now that explanation gave me also the idea that has bugged me for a while! Thanks for that idea. I was thinking of doing some sort of a number sign near those places but that will make it harder to see in that scale when things are on the opposite side of the layout.  Long distance vision getting poor!

[MarkF]

I have another question.
I have two spare tunnel portals.
Do you like this wooden one or the previous rock portal better?



I made both this wooden portal and the wood retaining wall covering the entrance in FreeCAD.

[MarkF]

At railroad crossing, there is a post with a 'W' on it that tells the loco engineer when to blow the whistle.  The posts look like 4"x4" about 4 ft high.  You could put a post at the insulator if it's near a crossing.




Here is an example of blue painted track ties:

[andy3055]

Thanks for the photos.  As for the tunnel portals,I like both. I think you have to think of what you are planning to do just outside those. Then, you can decide which one to use.

[MarkF]

Standing back and reviewing where I'm at with the layout, I thought
everyone might like to see a couple old pictures of the farm when I was little.

[andy3055]

Nice. I wish I had a farm... but with others to work there! Meaning a rich farmer 

[RoGeorge]

Give a ball to those cows, so they can play with it: