Breaking News
Blog

Poor contacts stop model trains on the track

NO RATINGS
View Comments: Newest First | Oldest First | Threaded View
<<   <   Page 3 / 3
agk
User Rank
Rookie
re: Poor contacts stop model trains on the track
agk   12/25/2010 2:39:44 PM
NO RATINGS
Yes zeeglen I had lot of pleasure and fun as you said while doing it for play

sharps_eng
User Rank
Rookie
re: Poor contacts stop model trains on the track
sharps_eng   12/24/2010 10:29:06 PM
NO RATINGS
I was disappointed how unsophisticated the electronics was in model rail, but like so many real-world situations there is so much legacy kit investment out there you can't innnovate overnight. Every newcomer confidently attempting to sweep away the troubles of past systems completely underestimates the challenges of power distribution, control technique and packaging of the circuits. Model rail as a whole is its own universe, with only passing similarities to other fields. So at the same time I have to be impressed with how much modernisation is getting done, much by hobbyists with no engineering background.

DWilde10
User Rank
Rookie
re: Poor contacts stop model trains on the track
DWilde10   12/24/2010 2:22:16 AM
NO RATINGS
Way to go, Glen! That's the spirit that makes American ingenuity world famous. As a lifetime follower of model railroading I contend that my study of Dad's cabinets full of Model Railroader magazines is one of the primary reasons I'm really good with complex embedded computer systems today...

zeeglen
User Rank
Blogger
re: Poor contacts stop model trains on the track
zeeglen   12/24/2010 2:01:10 AM
NO RATINGS
Yes, pulse width modulation in various forms is almost universal today thanks to the transistor. It makes a small motor develop a higher low speed torque than pure DC, very useful when performing operations such as realistic yard shunting or spotting freight cars on a siding. It can also overheat a motor if the voltage is too high with the duty cycle low (I^2R with very little back EMF), so the pulse peak must be kept within the limit of the motor full speed DC voltage rating. Many a Z scale motor has smoked at low speed when used with a PWM power pack intended for HO scale. In the article pulse width modulation was used but did not help the main problem which was the opening of the current flow to the motor. This was simply dirt and poor design. One of the fun things about model rail is combining the hobby with some of the cool things that can be done with electronics and mechanics. Sometimes after a hard day's debugging it is relaxing to come home, pick up a soldering iron, and build a gadget that flashes LEDs at a grade crossing. For examples see Model Railroad & Misc. Electronics http://home.cogeco.ca/~rpaisley4/CircuitIndex.html

zeeglen
User Rank
Blogger
re: Poor contacts stop model trains on the track
zeeglen   12/24/2010 1:27:25 AM
NO RATINGS
Aluminum develops a non-conductive surface oxide which will insulate current flow to the wheels. Model rail tracks today are almost always made of nickel silver (actually copper nickel zinc alloy) whose oxide is electrically conductive. Your switch cleaning oil probably retarded the buildup of oxide. It sounds like you had a lot of fun with the conversions. Nice when folks can use their engineering skills for "play". Not many careers provide that option.

gah4
User Rank
Manager
re: Poor contacts stop model trains on the track
gah4   12/23/2010 10:26:46 PM
NO RATINGS
I remember from many years ago, a quick Google search shows December 1965, a Popular Electronics article on a pulse power supply for model trains. I believe it used a constant pulse (width and amplitude) plus a variable DC to allow smooth control at slower speeds. Even larger gauge trains run poorly at the slowest speeds, but the article claimed that pulse power allowed slow operation.

agk
User Rank
Rookie
re: Poor contacts stop model trains on the track
agk   12/23/2010 3:46:30 PM
NO RATINGS
This article takes me back to year1992. I converted LEO hand pulled toy train engine compartments into electric train by fixing them with casette player motors,capstan shafts and pulleys.The metal wheels were from steei made in a lathe. The tracks were made from aluminium U channels(inverted) with wooden repers. Connect them with a battery adopter it use to run nice for some time and stops later due to the carbon deposited on the tracks and wheels. I got the idea of applying switch cleaning oil on the tracks and tested and found that it runs continiously for hours together.all the children around played the train and it was amusing!

<<   <   Page 3 / 3
More Blogs
Why is the National Highway Traffic Safety Administration such a slacker at enforcing safety laws? A US Senate subcommittee wants to investigate.
Apple and Samsung are poised to ship their first smartphones using 20nm mobile processors, but they are applying the silicon technology in radically different ways.
Dilbert remains a great source of comic relief, but the misimpressions from that comic about marketing should be viewed as nothing more than a spoof.
Perhaps this is the natural order of business -- Darwinism and RadioShack's impending demise open the door wider for companies like SparkFun and Adafruit to grow.
Gartner Hype Cycle pegs wearables, connected homes, and consumer 3D printing as 5 to 10 years away from becoming popular among most consumers.
Top Comments of the Week
August Cartoon Caption Winner!
August Cartoon Caption Winner!
"All the King's horses and all the KIng's men gave up on Humpty, so they handed the problem off to Engineering."
5 comments
Like Us on Facebook

Datasheets.com Parts Search

185 million searchable parts
(please enter a part number or hit search to begin)
EE Times on Twitter
EE Times Twitter Feed
Radio
LATEST ARCHIVED BROADCAST
David Patterson, known for his pioneering research that led to RAID, clusters and more, is part of a team at UC Berkeley that recently made its RISC-V processor architecture an open source hardware offering. We talk with Patterson and one of his colleagues behind the effort about the opportunities they see, what new kinds of designs they hope to enable and what it means for today’s commercial processor giants such as Intel, ARM and Imagination Technologies.
Flash Poll