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.
Model train electronics
Started by ●December 16, 2021
Reply by ●December 16, 20212021-12-16
On Thursday, December 16, 2021 at 3:28:33 PM UTC-4, 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.My understanding that nickle is used because nickle oxide is conductive, but on googling that it seems NiO is a semiconductor, not quite the same thing. What I have to wonder about is why model railroads aren't using onboard batteries and charging them through coils beneath the tracks or in a tunnel. There's got to be a better way than worrying about cleaning rails and wheels. BTW, what's wrong with a dry track??? That sounds like shade tree mechanics' talk. -- Rick C. - Get 1,000 miles of free Supercharging - Tesla referral code - https://ts.la/richard11209
Reply by ●December 16, 20212021-12-16
On 12/16/21 3:05 PM, Rick C wrote:> On Thursday, December 16, 2021 at 3:28:33 PM UTC-4, 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. > > My understanding that nickle is used because nickle oxide is conductive, but on googling that it seems NiO is a semiconductor, not quite the same thing. > > What I have to wonder about is why model railroads aren't using onboard batteries and charging them through coils beneath the tracks or in a tunnel. There's got to be a better way than worrying about cleaning rails and wheels.Laying good track is difficult enough for a hobbyist, much less laying down an inductive charging system. Maybe if it were built into the ready-made snap track that's also available but that limits topological options. It might work for the smaller gauges but IDK about 1:87 and larger. The stall current of an average HO 1:87 loco motor is already close to an amp. They're geared down perhaps 10:1 so 10k RPM maybe at 12 volts across the armature.. I think an inductive charging system will have trouble keeping multiple batteries you could fit in models that size charged for many hours the coupling won't be great and efficiency won't be great, either. Three rail track makes life easier with reversing loops and such, two-rail DC-powered is a mess of switches to avoid shorts if you get fancy, even with just one loco, more if you want to run more than one train. DCC/digital command and power over the rails simplifies wiring but is anecdotally more finicky about dirty track than DC. Another system uses constant DC for track power and radio control for commands. MRs are sometimes skeptical of a lot of that stuff they often tend to be as stuck-in-the-past as audiophiles. Even on old-fashioned DC power though using keep-alive capacitors in locos to minimize drop-outs on brief areas of dirty/dodgy track seems to be becoming more common; extending that to keep-alive battery seems feasible but then you have to re-design the whole motor drive scheme too.> BTW, what's wrong with a dry track??? That sounds like shade tree mechanics' talk.It's been claimed dry track increases "micro-arcing" but beats me if that hypothesis as to where a lot of the "dirt" comes from is even true.
Reply by ●December 16, 20212021-12-16
On Thursday, December 16, 2021 at 6:37:03 PM UTC-4, bitrex wrote:> On 12/16/21 3:05 PM, Rick C wrote: > > On Thursday, December 16, 2021 at 3:28:33 PM UTC-4, 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. > > > > My understanding that nickle is used because nickle oxide is conductive, but on googling that it seems NiO is a semiconductor, not quite the same thing. > > > > What I have to wonder about is why model railroads aren't using onboard batteries and charging them through coils beneath the tracks or in a tunnel. There's got to be a better way than worrying about cleaning rails and wheels. > Laying good track is difficult enough for a hobbyist, much less laying > down an inductive charging system. Maybe if it were built into the > ready-made snap track that's also available but that limits topological > options. > > It might work for the smaller gauges but IDK about 1:87 and larger. The > stall current of an average HO 1:87 loco motor is already close to an > amp. They're geared down perhaps 10:1 so 10k RPM maybe at 12 volts > across the armature.. I think an inductive charging system will have > trouble keeping multiple batteries you could fit in models that size > charged for many hours the coupling won't be great and efficiency won't > be great, either. > > Three rail track makes life easier with reversing loops and such, > two-rail DC-powered is a mess of switches to avoid shorts if you get > fancy, even with just one loco, more if you want to run more than one > train. DCC/digital command and power over the rails simplifies wiring > but is anecdotally more finicky about dirty track than DC. Another > system uses constant DC for track power and radio control for commands. > > MRs are sometimes skeptical of a lot of that stuff they often tend to be > as stuck-in-the-past as audiophiles. Even on old-fashioned DC power > though using keep-alive capacitors in locos to minimize drop-outs on > brief areas of dirty/dodgy track seems to be becoming more common; > extending that to keep-alive battery seems feasible but then you have to > re-design the whole motor drive scheme too.If they can fast charge a 100 kWh EV, I think a model train can be charged. If you are talking about a scale that's too large, let them feed wood or coal into the boiler.> > BTW, what's wrong with a dry track??? That sounds like shade tree mechanics' talk. > It's been claimed dry track increases "micro-arcing" but beats me if > that hypothesis as to where a lot of the "dirt" comes from is even true.How do they wet their tracks? I think you are talking about micro-fluff as in topical fluff. Like the silly stuff car or hi-fi enthusiasts do. -- Rick C. + Get 1,000 miles of free Supercharging + Tesla referral code - https://ts.la/richard11209
Reply by ●December 16, 20212021-12-16
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.Trains have more than two wheels. Use multiple pick-ups. RL
Reply by ●December 16, 20212021-12-16
On Thu, 16 Dec 2021 18:00:10 -0500, legg <legg@nospam.magma.ca> 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. > >Trains have more than two wheels. > >Use multiple pick-ups.That is the classic remedy. And/or sliding spring-loaded silver-graphite blocks on some kind of dancer. The mechanical resonance frequency needs to be high enough that the dancer won't dance too wildly. Joe Gwinn
Reply by ●December 16, 20212021-12-16
On Thu, 16 Dec 2021 19:58:56 -0500, Joe Gwinn <joegwinn@comcast.net> wrote:>On Thu, 16 Dec 2021 18:00:10 -0500, legg <legg@nospam.magma.ca> 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. >> >>Trains have more than two wheels. >> >>Use multiple pick-ups. > >That is the classic remedy. > >And/or sliding spring-loaded silver-graphite blocks on some kind of >dancer. The mechanical resonance frequency needs to be high enough >that the dancer won't dance too wildly. > >Joe GwinnThe contacting interface is track-to-wheel, as I understand it. Not much choice there. The use of multiple pick-ups reduces the loop area of stored energy to be quenched by arcing to the length of the wheelbase, removing the track-to source loop from the equation. RL
Reply by ●December 17, 20212021-12-17
On 17/12/2021 03:40, legg wrote:> On Thu, 16 Dec 2021 19:58:56 -0500, Joe Gwinn <joegwinn@comcast.net> > wrote: > >> On Thu, 16 Dec 2021 18:00:10 -0500, legg <legg@nospam.magma.ca> 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. >>> >>> Trains have more than two wheels. >>> >>> Use multiple pick-ups. >> >> That is the classic remedy. >> >> And/or sliding spring-loaded silver-graphite blocks on some kind of >> dancer. The mechanical resonance frequency needs to be high enough >> that the dancer won't dance too wildly. >> >> Joe Gwinn > > The contacting interface is track-to-wheel, as I understand it. > Not much choice there.Depends on the vintage of loco though. Older ones have the wheels for traction only and a separate pair of spring loaded contacts for power pick up. The pickup spring loading was adjustable and the pickups replaceable - they wear quite quickly. Proper locomotive models are live steam and commonly 3.5" or 5" gauge using anthracite for fuel. They will pull 3 or 4 bogeys full of kids. -- Regards, Martin Brown
Reply by ●December 17, 20212021-12-17
On 17/12/21 09:10, Martin Brown wrote:> Proper locomotive models are live steam and commonly 3.5" or 5" gauge using > anthracite for fuel. They will pull 3 or 4 bogeys full of kids.And then there's the hybrid 15" Romney Hythe and Dymchurch Railway, pulling 8 carriages full of adults along 15 miles of track. Great fun. https://www.rhdr.org.uk/images/rhdr_content_station_dymchurch.jpg
Reply by ●December 17, 20212021-12-17
On Thu, 16 Dec 2021 22:40:31 -0500, legg <legg@nospam.magma.ca> wrote:>On Thu, 16 Dec 2021 19:58:56 -0500, Joe Gwinn <joegwinn@comcast.net> >wrote: > >>On Thu, 16 Dec 2021 18:00:10 -0500, legg <legg@nospam.magma.ca> 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. >>> >>>Trains have more than two wheels. >>> >>>Use multiple pick-ups. >> >>That is the classic remedy. >> >>And/or sliding spring-loaded silver-graphite blocks on some kind of >>dancer. The mechanical resonance frequency needs to be high enough >>that the dancer won't dance too wildly. >> >>Joe Gwinn > >The contacting interface is track-to-wheel, as I understand it. >Not much choice there.Sure there is - use two wheels on each rail, for a total of four electricity-carrying wheels. The game is that there will be at least one wheel on each track at almost all times, sharply reducing sparking and thus spark erosion.>The use of multiple pick-ups reduces the loop area of stored >energy to be quenched by arcing to the length of the wheelbase, >removing the track-to source loop from the equation.These loops do not have nearly enough inductance to that to be significant. It's the motor load inductance that's the issue. Joe Gwinn