Model train electronics

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

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.

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

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
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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.

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

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
...

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

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.

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.