Model train electronics...

[Don Y]

On 12/18/2021 7:45 AM, bitrex wrote:

The largest ones are owned and operated by clubs, that type they can and do
operate like a real railroad. Print up waybills, have virtual industries, make
up and break down the trains and send the \"goods\" where they need to go.
There\'s no shortage of people actually in the transit/logistics industry
involved in the hobby (though often retired.)

TMRC had a decent size layout. IIRC, they used an old crossbar switch to
control the switching, displayed \"scale time\" on the wall, etc. I think it
was transitioning to a small \'11 about the time I was on campus.

It was not uncommon to find a single soul sitting in the room tweaking
the controls, layout, etc.

Much like people garden, restore old vehicles/aircraft or any other
\"distraction\" that allows you to exercise some creativity in a relatively
low-pressure situation.

So much different than being *told* what your goal will be and just
working towards that (regardless of the level of expertise required).

The difference between accounting and storycraft.

One can appreciate the skill that goes into reifying a story on the
big-screen. That\'s just another type of \"engineering\".

But, by far, the more awesome task is coming up with the story and the
vision in the first place! I don\'t know any engineers that have imaginations
that are THAT \"unconstrained\"! (and, certainly none that willing to make
a commitment to PROVE it!)

And sometimes it\'s mostly art like this Great Depression-era layout was largely
scratch-built by one guy over 25 years or so:

There are several museums that have *really* large layouts. One of the
hardware stores, here, has a layout above the heads of shoppers. Folks
can\'t help but watch the train as it passes by, overhead.

But, like restoring/maintaining old vehicles, it seems like you\'d
forever be \"fixing something\" -- just to tread water!

 

[Rich S]

On Saturday, December 18, 2021 at 11:59:40 AM UTC, Mike Coon wrote:

In article <72rprgd31n7et0eh5...@4ax.com>,
jlarkin@highland_atwork_technology.com says...

The trains go round and round. Is that amusing, or is the construction
the whole point?
If the layout is just a Circle Line I\'m sure construction and
elaboration is the only point.

But people have constructed layouts that replicate shunting logic
puzzles. And maybe even those ethics challenges of whether to save one
trespasser or several linesmen (etc)...

Agree, the model train (and similar hobbies) stay with us
even into adulthood. They can teach us basic science
in a fun way, and later, nostalgia takes hold. I recall
the rare luxury, mom got me the kid, an AHM HO-scale
set one xmas. (Very basic, as AHM is normally pricey).
It taught me basic electricity and physics. Later, the
power pack served me for a while in powering other
electronic projects (and later, ponder, why did the
manufacturer use selenium rectifier diodes when
silicon was so ubiquitous and cheap....)

 

[Tabby]

On Thursday, 16 December 2021 at 19:28:33 UTC, bitrex wrote:

The foamers have come to the conclusion that a reason their tracks get
\"dirty\" and cause power drop-outs is in large part due to nickel oxides
deposited on the nickel silver rail surface from micro-arcing and
microscopic pitting caused by the pick-up wheels.

So they look for a surface coating or cleaner that reduces micro-arcing
(if that really is the main reason) but doesn\'t affect traction too
much; anhydrous isopropyl is thought inappropriate because it leaves the
rail surface too dry after it evaporates, some swear by mineral spirits,
I guess some use a thin coating of automatic transmission fluid.

Is it possible to rather reduce the micro-arcing at the source through
some kind of snubbing or is that not really feasible wrt the process
described.

very much so. A big cap across the motor helps. A flywheel would help too. Don\'t know if lead in the loco might improve contact too.
I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.

 

[server]

On Fri, 24 Dec 2021 00:54:49 -0800 (PST), Tabby <tabbypurr@gmail.com>
wrote:

On Thursday, 16 December 2021 at 19:28:33 UTC, bitrex wrote:
The foamers have come to the conclusion that a reason their tracks get
\"dirty\" and cause power drop-outs is in large part due to nickel oxides
deposited on the nickel silver rail surface from micro-arcing and
microscopic pitting caused by the pick-up wheels.

So they look for a surface coating or cleaner that reduces micro-arcing
(if that really is the main reason) but doesn\'t affect traction too
much; anhydrous isopropyl is thought inappropriate because it leaves the
rail surface too dry after it evaporates, some swear by mineral spirits,
I guess some use a thin coating of automatic transmission fluid.

Is it possible to rather reduce the micro-arcing at the source through
some kind of snubbing or is that not really feasible wrt the process
described.

very much so. A big cap across the motor helps. A flywheel would help too. Don\'t know if lead in the loco might improve contact too.
I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.

Why not gold plate everything?



--

I yam what I yam - Popeye

 

[Three Jeeps]

On Friday, December 17, 2021 at 3:05:10 PM UTC-5, John Larkin wrote:

On Fri, 17 Dec 2021 14:29:32 -0500, Joe Gwinn <joeg...@comcast.net
wrote:
On Fri, 17 Dec 2021 10:53:17 -0800, John Larkin
jlarkin@highland_atwork_technology.com> wrote:

On Thu, 16 Dec 2021 14:28:26 -0500, bitrex <us...@example.net> wrote:

The foamers have come to the conclusion that a reason their tracks get
\"dirty\" and cause power drop-outs is in large part due to nickel oxides
deposited on the nickel silver rail surface from micro-arcing and
microscopic pitting caused by the pick-up wheels.

So they look for a surface coating or cleaner that reduces micro-arcing
(if that really is the main reason) but doesn\'t affect traction too
much; anhydrous isopropyl is thought inappropriate because it leaves the
rail surface too dry after it evaporates, some swear by mineral spirits,
I guess some use a thin coating of automatic transmission fluid.

Is it possible to rather reduce the micro-arcing at the source through
some kind of snubbing or is that not really feasible wrt the process
described.

Just curious, why would grown men play with model trains?

It\'s sorta like grown men chasing picoseconds through components the
size of peppercorns?
Designing electronics is continuously interesting, and makes money as
opposed to spending it.

The trains go round and round. Is that amusing, or is the construction
the whole point?

We wouldn\'t have enough room anyhow.

(I outgrew trains, and gave what remained to my nephew, who didn\'t
stay interested all that long.)
I had a train set as a kid, but mostly took them apart.


(I expect that few women do.) F

I bet there is at least one unsuspecting girl who inherited her
father\'s passion for model trains.

I\'ve seen lots of youtube videos of young women running metal working
lathes, and clearly know what they are doing - probably grew up with
it, often on a farm.
One extremely expensive private high school near here has mandatory
courses in electronics and welding.
--

If a man will begin with certainties, he shall end with doubts,
but if he will be content to begin with doubts he shall end in certainties.
Francis Bacon

For a period of time (mid 70s-mid 80\'s) it was often a senior project for EE\'s - the application of micros to control somewhat elaborate HO train layouts. Things grew beyond sensing discrete position and coordinating switching to techniques to PWM a signal on the tracks to address various trains to control some event. More challenging scenarios would include consideration of various faults.
With the advent of IoT devices, all sorts of various use scenarios could be thought out and applied by Jr and Sr EE students.

 

[ke...@kjwdesigns.com]

....
> very much so. A big cap across the motor helps.

Ones using electronic control (DCC) frequently do put as a large a capacitor as can be fitted. Ones without electronics on-board have a difficulty in that the track could be of either polarity.

>A flywheel would help too.

The better locos do have as large a flywheel as can be fitted.

>Don\'t know if lead in the loco might improve contact too.

Any spare space is usually filled with lead to increase the weight, there is just not much room in the loco to provide much weight.

> I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.

kw

 

[ke...@kjwdesigns.com]

On Friday, 24 December 2021 at 06:10:24 UTC-8, jla...@highlandsniptechnology.com wrote:
....

I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.
Why not gold plate everything?

Wouldn\'t help - the issue is contamination. It is not feasible to gold-plate the nickel-silver track anyway.

kw
>

 

[John Larkin]

On Fri, 24 Dec 2021 10:38:25 -0800 (PST), \"ke...@kjwdesigns.com\"
<keith@kjwdesigns.com> wrote:

On Friday, 24 December 2021 at 06:10:24 UTC-8, jla...@highlandsniptechnology.com wrote:
...
I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.
Why not gold plate everything?

Wouldn\'t help - the issue is contamination. It is not feasible to gold-plate the nickel-silver track anyway.

kw

Our PCBs are all ENIG now, gold over nickel.

--

If a man will begin with certainties, he shall end with doubts,
but if he will be content to begin with doubts he shall end in certainties.
Francis Bacon

 

[Rick C]

On Friday, December 24, 2021 at 4:11:42 PM UTC-5, John Larkin wrote:

On Fri, 24 Dec 2021 10:38:25 -0800 (PST), \"ke...@kjwdesigns.com\"
ke...@kjwdesigns.com> wrote:

On Friday, 24 December 2021 at 06:10:24 UTC-8, jla...@highlandsniptechnology.com wrote:
...
I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.
Why not gold plate everything?

Wouldn\'t help - the issue is contamination. It is not feasible to gold-plate the nickel-silver track anyway.

kw

Our PCBs are all ENIG now, gold over nickel.

The gold is microinches thick. It would wear away quickly from model railroad use. Even so, the cost would not be insignificant. They charge for gold even on small PCBs. Some yards of track would add some dollars to the cost.

--

Rick C.

-- Get 1,000 miles of free Supercharging
-- Tesla referral code - https://ts.la/richard11209

 

[Tabby]

On Friday, 24 December 2021 at 18:37:17 UTC, ke...@kjwdesigns.com wrote:

...
very much so. A big cap across the motor helps.
Ones using electronic control (DCC) frequently do put as a large a capacitor as can be fitted. Ones without electronics on-board have a difficulty in that the track could be of either polarity.

2 caps, each with 2 diodes would solve that.

A flywheel would help too.
The better locos do have as large a flywheel as can be fitted.
Don\'t know if lead in the loco might improve contact too.
Any spare space is usually filled with lead to increase the weight, there is just not much room in the loco to provide much weight.
I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.
kw

 

[Jan Panteltje]

On a sunny day (Fri, 24 Dec 2021 10:38:25 -0800 (PST)) it happened
\"ke...@kjwdesigns.com\" <keith@kjwdesigns.com> wrote in
<73b264cd-5d11-4957-a8f2-0b6eebcd7bedn@googlegroups.com>:

On Friday, 24 December 2021 at 06:10:24 UTC-8, jla...@highlandsniptechnology.com wrote:
...
I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.
Why not gold plate everything?

Wouldn\'t help - the issue is contamination. It is not feasible to gold-plate the nickel-silver track anyway.

kw

Why not put a big lipo in the locomotive, and do inductive charging at points where the train stops?
Add WiFi or something to control speed.
Or solar cells on the roofs of the carriages and a big spotlight above.
you have to go with the times.... ;-)

That said, I never had an electric toy train.

 

[Joe Gwinn]

On Fri, 24 Dec 2021 15:45:14 -0800 (PST), Rick C
<gnuarm.deletethisbit@gmail.com> wrote:

On Friday, December 24, 2021 at 4:11:42 PM UTC-5, John Larkin wrote:
On Fri, 24 Dec 2021 10:38:25 -0800 (PST), \"ke...@kjwdesigns.com\"
ke...@kjwdesigns.com> wrote:

On Friday, 24 December 2021 at 06:10:24 UTC-8, jla...@highlandsniptechnology.com wrote:
...
I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.
Why not gold plate everything?

Wouldn\'t help - the issue is contamination. It is not feasible to gold-plate the nickel-silver track anyway.

kw

Our PCBs are all ENIG now, gold over nickel.

The gold is microinches thick. It would wear away quickly from model railroad use. Even so, the cost would not be insignificant. They charge for gold even on small PCBs. Some yards of track would add some dollars to the cost.

Silver plating the tracks could work. But multiple sliding/rolling
contacts per real is still needed.

Joe Gwinn

 

[Rick C]

On Saturday, December 25, 2021 at 11:03:15 AM UTC-5, Joe Gwinn wrote:

On Fri, 24 Dec 2021 15:45:14 -0800 (PST), Rick C
gnuarm.del...@gmail.com> wrote:

On Friday, December 24, 2021 at 4:11:42 PM UTC-5, John Larkin wrote:
On Fri, 24 Dec 2021 10:38:25 -0800 (PST), \"ke...@kjwdesigns.com\"
ke...@kjwdesigns.com> wrote:

On Friday, 24 December 2021 at 06:10:24 UTC-8, jla...@highlandsniptechnology.com wrote:
...
I\'m no model train fan, but IIUC arcing burns away some of the crud causing arcing, so it\'s not a one sided thing.
Why not gold plate everything?

Wouldn\'t help - the issue is contamination. It is not feasible to gold-plate the nickel-silver track anyway.

kw

Our PCBs are all ENIG now, gold over nickel.

The gold is microinches thick. It would wear away quickly from model railroad use. Even so, the cost would not be insignificant. They charge for gold even on small PCBs. Some yards of track would add some dollars to the cost.
Silver plating the tracks could work. But multiple sliding/rolling
contacts per real is still needed.

I don\'t think silver is an improvement over nickle is it? It\'s not like silver doesn\'t tarnish.

--

Rick C.

-+ Get 1,000 miles of free Supercharging
-+ Tesla referral code - https://ts.la/richard11209

 

[Ralph Mowery]

In article <335a5b40-bd95-4111-8c6a-da6128561fafn@googlegroups.com>,
gnuarm.deletethisbit@gmail.com says...

I don\'t think silver is an improvement over nickle is it? It\'s not like silver doesn\'t tarnish.

Silver will tarnish but silver oxide is suppose to be a good conductor
where other oxides are not good condctors.

Silver costs too much and silver plate will ware off too soon.

 

[ke...@kjwdesigns.com]

On Friday, 24 December 2021 at 18:48:40 UTC-8, Tabby wrote:
....

very much so. A big cap across the motor helps.
Ones using electronic control (DCC) frequently do put as a large a capacitor as can be fitted. Ones without electronics on-board have a difficulty in that the track could be of either polarity.
2 caps, each with 2 diodes would solve that.

In the smaller scales that suffer from track connectivity it is difficult (maybe impossible) to find space for a single cap, let alone 2 of adequate value.

kw

 

[ke...@kjwdesigns.com]

On Saturday, 25 December 2021 at 08:03:15 UTC-8, Joe Gwinn wrote:
....

The gold is microinches thick. It would wear away quickly from model railroad use. Even so, the cost would not be insignificant. They charge for gold even on small PCBs. Some yards of track would add some dollars to the cost.
Silver plating the tracks could work.

Most model railway track is made of nickel-silver that possesses the useful characteristic that the oxide is (somewhat conductive). Silver is similar.

> But multiple sliding/rolling contacts per real is still needed.

The better quality locomotives already use all the weight bearing wheels as current collectors.

kw
....

 

[ke...@kjwdesigns.com]

On Saturday, 25 December 2021 at 10:25:47 UTC-8, Ralph Mowery wrote:

In article <335a5b40-bd95-4111...@googlegroups.com>,
gnuarm.del...@gmail.com says...

I don\'t think silver is an improvement over nickle is it? It\'s not like silver doesn\'t tarnish.



Silver will tarnish but silver oxide is suppose to be a good conductor
where other oxides are not good condctors.

Nickel-silver that the tracks are made of is similar. Nickel silver is mainly copper together with nickel and zinc.
....
kw

 

[Tabby]

On Saturday, 25 December 2021 at 18:54:33 UTC, ke...@kjwdesigns.com wrote:

On Friday, 24 December 2021 at 18:48:40 UTC-8, Tabby wrote:
...
very much so. A big cap across the motor helps.
Ones using electronic control (DCC) frequently do put as a large a capacitor as can be fitted. Ones without electronics on-board have a difficulty in that the track could be of either polarity.
2 caps, each with 2 diodes would solve that.
In the smaller scales that suffer from track connectivity it is difficult (maybe impossible) to find space for a single cap, let alone 2 of adequate value.

kw

Custom shaped caps could help, but it all ups the price.
I suspect pouring a little lead into any vacant spaces would have more effect, IIUC the problem really stems from inadequate downforce.

 

[David Eather]

On 17/12/2021 5:28 am, bitrex wrote:

The foamers have come to the conclusion that a reason their tracks get
\"dirty\" and cause power drop-outs is in large part due to nickel oxides
deposited on the nickel silver rail surface from micro-arcing and
microscopic pitting caused by the pick-up wheels.

So they look for a surface coating or cleaner that reduces micro-arcing
(if that really is the main reason) but doesn\'t affect traction too
much; anhydrous isopropyl is thought inappropriate because it leaves the
rail surface too dry after it evaporates, some swear by mineral spirits,
I guess some use a thin coating of automatic transmission fluid.

Is it possible to rather reduce the micro-arcing at the source through
some kind of snubbing or is that not really feasible wrt the process
described.

I cant see any reason why a snubber across the tracks (and maybe one in
the engine for good measure) wouldn\'t work a treat.

 

[Flyguy]

On Thursday, December 30, 2021 at 5:18:22 PM UTC-8, Tabby wrote:

On Thursday, 30 December 2021 at 00:44:30 UTC, David Eather wrote:
On 17/12/2021 5:28 am, bitrex wrote:
The foamers have come to the conclusion that a reason their tracks get
\"dirty\" and cause power drop-outs is in large part due to nickel oxides
deposited on the nickel silver rail surface from micro-arcing and
microscopic pitting caused by the pick-up wheels.

So they look for a surface coating or cleaner that reduces micro-arcing
(if that really is the main reason) but doesn\'t affect traction too
much; anhydrous isopropyl is thought inappropriate because it leaves the
rail surface too dry after it evaporates, some swear by mineral spirits,
I guess some use a thin coating of automatic transmission fluid.

Is it possible to rather reduce the micro-arcing at the source through
some kind of snubbing or is that not really feasible wrt the process
described.

I cant see any reason why a snubber across the tracks (and maybe one in
the engine for good measure) wouldn\'t work a treat.
I can\'t see a track snubber helping.

Or you can skip power transmission thru the rails altogether and have on-board batteries with radio control:
https://www.s-cab.com/
You can have multiple locomotives operate simultaneously on the same track.