Model train electronics

On 12/18/21 10:51 AM, jlarkin@highlandsniptechnology.com wrote:
> On Sat, 18 Dec 2021 09:50:09 -0500, bitrex <user@example.net> wrote:
> 
>> On 12/18/21 9:45 AM, bitrex wrote:
>>> On 12/17/21 3:04 PM, John Larkin wrote:
>>>> On Fri, 17 Dec 2021 14:29:32 -0500, Joe Gwinn <joegwinn@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 <user@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?
>>>
>>> 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.)
>>>
>>> And sometimes it's mostly art like this Great Depression-era layout was
>>> largely scratch-built by one guy over 25 years or so:
>>>
>>> <https://youtu.be/vvbg_tL9JXM>
>>
>> Though I believe George Selios also ran a business selling kits for some
>> of the structures and pieces he designed, Fine Scale Miniatures, so
>> wasn't entirely a money-sink
>>
> 
> Someone gave us an giant elaborate wooden Christmas village thing
> custom-hand-build by some old guy in Germany. I'm not sure what we'll
> do with it.

I bet someone in SF would be interested, but probably not big money, 
sadly the market for handcrafted projects by individuals isn't hot, even 
when the workmanship is exceptional. A small model railroad someone sunk 
$5000 into might sell for $750 I have a couple custom guitars I 
assembled from maybe 2k worth of parts per they'd fetch maybe the same 
$750 if I went to sell them as a unit and not part out.

They're nicer instruments for playing than some made by e.g. Fender at 
similar price point but the value of some of the latter will only tend 
to go up because they're branded. Particularly if they discontinued a 
particular model without making too many due to lack of sales...

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!

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....)

 

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.

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

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.  

...
> 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

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
> 

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

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.

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