What point motors?

 
  wolfpac Minister for Railways

Location: Over here...
Do you have something to switch frog polarity with the ANE setup or would that be additional?
SAR523

Pack 004 includes the frog polarity switching board and the DCC stationary decoder (and 4 servos - either 4 switches, boomgates or 2+2 crossover etc etc)

I use Pack 003 on my Freemo AU Modules, DCC stationary decoder utilising Peco #6 code 83 Insulfrog points and 3x Atlas #8 switches.

You can get 003 then add on the frog polarity switching board at a later date if you decide to go live frogs.

Or even get 001 and add on a DCC stationary decoder, then a frog switcher later, too. Very customisable and configurable setup ANE have.

Wolfpac

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  glagsniffer Junior Train Controller

Location: near liverpool, sydney
thanks for all the input guys! some (sort of) good news is i missed out on the bulk load of code 100 points i was bidding on so now after some discussion i can look at code 75, i had the idea that code 100 would mean less derailments and i was opting for trouble free running, looking carefully at some other layouts i have been converted... although i'm still looking into the differing options for point motors as long as the new peco stuff is cost effective it is looking likely with servo's a close second, either way an experiment or two should sort me out before buying 20ish point motors that will disappoint!
  trawny Train Controller

Location: Victoria
thanks for all the input guys! some (sort of) good news is i missed out on the bulk load of code 100 points i was bidding on so now after some discussion i can look at code 75, i had the idea that code 100 would mean less derailments and i was opting for trouble free running, looking carefully at some other layouts i have been converted... although i'm still looking into the differing options for point motors as long as the new peco stuff is cost effective it is looking likely with servo's a close second, either way an experiment or two should sort me out before buying 20ish point motors that will disappoint!
glagsniffer

How were you planning on controlling the servos should you not go the peco path?

I've been looking at ardunios and reckon I might need to buy a starter kit (like this http://www.jaycar.com.au/productView.asp?ID=XC4262) and have a look at how they would go. I reckon they would be pretty flexible with more options of programming coordinated point movement, signals, level crossings and boom gates. Has anyone else used arduinos or similar programming boards?
  dthead Site Admin

Location: Melbourne, Australia
thanks for all the input guys! some (sort of) good news is i missed out on the bulk load of code 100 points i was bidding on so now after some discussion i can look at code 75, i had the idea that code 100 would mean less derailments and i was opting for trouble free running, looking carefully at some other layouts i have been converted..
glagsniffer

The size of the rail has no relation to derailments - any track has to be laid well.

Have fun !

David Head
  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
Okay, so I have taken some photos, but first a somewhat gratuitous shot of the panel controlling this section of the tramway. Why? Well I am particularly proud of this one, still in incomplete, draft form, but just about fully functional at this point. Controls and monitors the status of thirteen points, monitors and displays occupancy of 24 'blocks', will soon run the signalling, equipped with RailCom, this panel has just about everything I could think to implement. Hand made panel, hand made circuit boards, hand coded firmware (100+ pages of assembly coding), it has been a big task - but I only had to do it once now I can copy the design to other panels around the club. If you want something similar on your own layout I suggest you spend money buying rather than trying to design and implement such a thing yourself - unless of course like me you're truly in need of a challenge and entertainment. A less 'digital' and more 'analogue' approach might be the go normally.

Everything happens over six wires to the outside world. Some superfluous wiring has managed to remain in this photo.

So here's a view of the servo point motors, as you can see I use an 8g servo as I have rediscovered when taking the photos, the mounting is a custom (and hastily) made bracket which I nibbled from a length of 1/2" right angle section of aluminium. The point is actuated by a length of piano wire which passes through a fairly tolerance hole in the aluminium bracket to provide the fulcrum point.

Here's a shot of several of the servo motors in close succession, still with plenty of room around them.

A 'normal' railway will have no issues fitting them, these points are placed under trackage modified to come down to 40mm centres.
         
         

Here's a couple of shots of the servo point motors wired to their decoders. The thicker yellow and blue wires are the DCC track bus, the three way tag strip is what I use to create junctions between the bus and the trackage, in these photos my 'dropper' wires appear to be yellow and blue too, but that is not generally the case, normally they are a catalogued set of special colours. The thicker red and white wires are the power bus carrying the requisite 5 volts to the decoders, and hence to the servo motors. And the thinner grey and orange wires are carrying a special high reliability version of the DCC track wiring. Even under a total short circuit of the trackage (caused by a tram running against a point) the grey and orange wires still carry control signalling to enable the points to move, clear the short and allow traction current to return to the track. The green (and red and black) wires are carrying switched traction current from the decoder's relay to the point frog above.
         

In an attempt to minimise some cost (with exponential increase in difficulty of circuit design) I have made double and quad version of the control board. The single double board costs me about $2.53 less to make than two single boards... A quad board saves THREE times that amount against four single boards!!! I never claimed to be an economist!
Again, pink and brown are supplying current to point frogs.

Here's a four board with it's associated tangle of excess wiring on the way out to the various servo motors.

And a better shot of another quad board, this one actually only drives two points. The other two motors operating a pair of swing gates at the entrance of the yard, which open and close according to the state of the points. Being only partially implemented, I disconnected much of the wiring and dropped it down from under the layout for the photo.

So to some videos, with some apology for the video quality, I was driving the layout via my iPad whilst filming on the iPhone and constantly running out of hands to hold both devices whilst holding myself steady in awkward position under and over the layout...

So here you see a point moving under the power of a servo, the motion range here is not quite perfect, but it is sufficiently close until I summons the inclination required to amend the relevant CV to make it perfect. I also apologise for the incomplete ballasting, I didn't notice until I watched the video back...
https://www.flickr.com/photos/79705948@N05/14108035759/in/set-72157644901416855
Here is another pair of points forming a double track Y junction, lovingly scratch built, still in an incomplete section. This is the area where the track centres are down to 40mm, note the crossing in the background, that is where the common mounted servo motors pictured above hang out. I also thought that I moved both points in this movie, apparently not...
https://www.flickr.com/photos/79705948@N05/14108038849/in/set-72157644901416855
Here's the normal crossing, both points move together and technically at the same time, they share common decoder wiring and have the same address, yet due to adjustable delays, etc, they apparently move independently of each other.
https://www.flickr.com/photos/79705948@N05/14292765252/in/set-72157644901416855
Finally, here's a video (of the servo driving the point in the first video) moving under the layout, for those that like the behind the scenes look.
https://www.flickr.com/photos/79705948@N05/14314898993/in/set-72157644901416855
  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
How were you planning on controlling the servos should you not go the peco path?

I've been looking at ardunios and reckon I might need to buy a starter kit (like this http://www.jaycar.com.au/productView.asp?ID=XC4262) and have a look at how they would go. I reckon they would be pretty flexible with more options of programming coordinated point movement, signals, level crossings and boom gates. Has anyone else used arduinos or similar programming boards?
"trawny"
I use mostly Microchip (PIC) product, mostly because that is what I am most familiar with, but also because they are more flexible than the Arduino. I own five Arduinos but I would (literally) have a few hundred PICs laying around here. As an aside and purely FYI, the panel I made above contains 6 PICs and an ATtiny, I used the ATtiny because it was spare and the PIC I originally used got reprogrammed to be something more useful - a DCC auto reverse.

The thing about open source (Arduino) is that the quality of the result that you get is dependant on the quality accepted by whoever wrote your library for free. Some of the Arduino libraries are pretty good, some of them are pretty far from that. I can make a PIC do some tasks way quicker than an Arduino, and that is mostly down to the lousy Arduino libraries, and sometimes down to the compiler doing odd things to slow the program down. That said, if you don't want to learn assembly...

If you take the Arduino path, I'd recommend checking out methods of using the Arduino's analogue pins as inputs. It should be possible to have the 5 pins supply sufficient inputs to use all 13 digital outs enabling you to drive 13 servos under points.
  vrwalker Station Master

I would like to stick up for the Cobalt motors.

I have successfully used the 'digital' variety and love the ease of convenience, 2 wires to the track bus and one for frog polarity. Easy to address and so far solid as a rock. Relatively inexpensive in the 6 or 12 pack and good instructions online.
  rob_downunder Station Staff

Aaron,

Thanks for posting the photos.  I think I will try something similar to your aluminium angle for the servo brackets.  I have just received MERG kits for the servo drivers and servos from Ebay so I had better get cracking.

Cheers,


Rob
  miktrain Deputy Commissioner

Location: Adelaide SA
So to some videos...

...Here is another pair of points forming a double track Y junction, lovingly scratch built, still in an incomplete section. This is the area where the track centres are down to 40mm, note the crossing in the background, that is where the common mounted servo motors pictured above hang out. I also thought that I moved both points in this movie, apparently not...
https://www.flickr.com/photos/79705948@N05/14108038849/in/set-72157644901416855
Aaron


So nice to see my scratch built points actually moving.

Tony
  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
Do show us how you get on Rob, I really must get around to joining MERG, especially since in the last week I have now redesigned my own DCC system to implement CAN alongside XpressNet*. You've got the CAN servo boards I gather?

I made my mounts from 1/2" angle. I used a hand nibbling tool to remove the required material in about 2x5mm chunks. Do yourself a favour and don't do what I did and make all thirteen of them by this method in one night (whilst watching Pulp Fiction). The muscle ache the next day was nearly terminal.

*Just in case anyone is actually interested, the micro controller I first used to run the Lenz v3 software cost me $1.48, to run the Lenz v3.6 software I had to update/upgrade the micro controller to one that cost $2.21, the new device to run the Lenz v3.6 interrupts and CAN frames simultaneously costs $14.42. On top of that I now have to make a new PCB too, it's no wonder DCC manufacturers are not big on producing upgrades.

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