Envisioning DCC........

[macdon]

Hello everyone!

 

While waiting for my first few basic newbie parts (M2, EF210, couple of rolling stock and a transformer), I thought that I would develop my layout plan based on the Amherst 2005/Manning Oaks track plan using Railmodeller.

 

After a bit of research, it dawned on me that the features of DCC does sound interesting and I feel that it will further enhance my experience in this hobby. Thus, I thought that it would be best to integrate the system on the onset of a layout rather than later when it is done.

 

I am submitting below a thumbnail pic of my proposed track plan in hopes that some of you may offer advices, comments and suggestions to properly guide me thru this journey. 

 

The basic parameters would be the ff - limited to only a 3'x6'(ish) layout, planning on using a Digitrax Zephyr Xtra and to be running 2 trains (maybe 3?) independently at the same time.

 

I guess for starters, it would be the wiring - so I have a few questions:

 

1. While this may be best answered depending on the track layout plan, how does one know where to place power feeders for DCC?

Im a bit confused as some say that in a small layout of 3x6 and having 2 main oval lines - one for the inner and one for the outer is enough, some say to place a feeder every 3'-4'........... while some solder power to every piece of track (hard act to follow).

 

2.  If I badly needed to add more power feeder points to my layout, would a 24-818 Kato Terminal Unijoiners help rather than soldering the track with power wires?

 

3.  Could I temporarily use the Kato transformer for controlling the Kato switches for the turnouts? (while deciding to elect toggle switches or a digital connection thru Zephyr).

 

Hope you guys can help a newbie out :)

 

Mardon

 

 

[cteno4]

Mardon,

 

good start! main comment on the track plan is those are pretty tight curves. larger trains will really look odd on them and some may not perform well on that tight of radius. you might try looking at moving the loop to the edge of the table all the way around to give you the max running length on a small loop like this so the trains will be a bit longer running before coming around again. on this small of a layout think smaller trains and give yourself room to do some scenery. might think of doing a little hillside to cover one corner of the track so trains disappear for a while. storage tracks are great to show off trains, but on a small layout like this they will take up a lot of room, so perhaps limit them to the minimum and keep them functional as well with platforms so you can have some interesting operations.

 

another option is to give up double track and go to a folded loop over and under to give you more running distance. then with dcc you could even run two trains on the single line even in different directions with passing sidings at platfroms and have some interesting operations. or do some shunting in a small set of sidings while something is running on the main line.

 

with the bridges are you going to put this on foam then carve out an area for a stream/canal?

 

DCC is fun, but really optional to get started. you can convert a small layout like this in a snap to dcc. not a lot of worry about needing a lot of feeders on this small of a layout. add a few extra unijoiner feeders on the mains in the curve. you can add feeders to the spurs if you want and then just join them all up to the dcc when you go that route or leave them unconnected to do the dc and use the unitrak power routing to turn them on and off. soldering every track is way overkill even for dcc. small loops like this im guessing 2-4 feeds per loop is plenty! one or two will do DC control fine on this small of a layout. DCC usually brings up a wide range of debate/experience on issues like this. This is why i say with this simple of a setup start with dc and get going and comfortable then ease into the DCC as it can be confusing to try to do it all at once for some.

 

switch control is easy you can just provide the kato controllers with 12v dc from a wall art or from a kato power pack if you have one sitting around to fire them that way. also there is a very simple capacitor discharge circuit (no electronics needed just wire with a screw terminal strip) that uses toggle switches to indicate direction or add leds even to it to make a fancy control board if you want. later you can then control by dcc. 

 

might take a look at the small layout threads that have come up here. there are some fun ideas to pack a lot into a small space while still having a lot of room for scenery and not feeling like you are always on a small loop. some are really small but basic idea could get scaled up some.

 

http://www.jnsforum.com/community/topic/6365-a-coffee-table-sized-layout/

 

http://www.jnsforum.com/community/topic/5904-a-small-tomix-layout/

 

http://www.jnsforum.com/community/topic/4541-small-industrial-layout/

 

http://www.katomodels.com/unitrackplan/

 

keep us posted and enjoy, looks like you are off to a great start in your planning!

 

jeff

[macdon]

Hi Jeff,

 

Thanks for the heads up! Both the original amherst and manning plans have an even tighter inside loop of 110. I changed mine by using 120 for the inner and 132 for the outer - which barely fits my small layout. Yeah, I never really imagined longer trains so definitely no shinkansens. Sadly, I had to work with the allowable space I have.

 

Yup, the bridges are for water - either creeping part of a lake, a small canal or even a flowing river if I elect to dissect the layout across the other side.

35yrs ago I wanted to try a small lake when I was doing Linn Westcott's plan, but was too chicken to try - this time, I'll try to attempt making one.

As for the scenery inside the loop - honestly, thats still up in the air. Of course,  Im electing some industrial branches as that would be one of the "playing" factors of the layout - so either a full industry scene or a mix with a small residential or commercial structures. All those mixed with a water scene does have its challenges - but definitely part of the planning.

 

I really do have a plan of placing a mountain on the top left side of the layout with tunnels for the tracks - but never thought of showing it in the track plans as my querry is on wiring.  Actually, only the mountain and the water feature are the definite ones that I have envisioned - industries, residential dwellings and/or commercial establishments are still up in the air.

 

Thanks again!

 

Mardon

[cteno4]

Mardon,

 

cool, short trains will be fine then! 

 

on the buildings make sure to do some quick fiddling with squares approx size of bases to get a feel for what you want for buildings to make sure you have room for the main items you may want. space gets eaten up fast on small layouts! 

 

other thing is to take your best shot at track planning, buy the track and just set it up and play with it. if you find you dont like some things then the beauty of unitrak is you can buy a bit more track and modify till you get it the way you want it before you start nailing stuff down! better than getting everything in place and realizing you are not happy and ripping stuff up or worse loosing interest!

 

if your water is not a huge area there are some interesting simple techniques of painting the desired water colors and then painting on plain old white PVA glue on top to simulate a nice water surface with details as needed. you can make small ripples, boat trails, waves, etc in the glue. its done a lot in japan on mini layouts and dioramas and you can get great water effects w/o having to try to pour water surfaces from epoxy, etc. grab a piece of cardboard and play! 

 

perhaps a stream under the bridge that then goes into a channel and under ground with buildings, street, tracks over it. this happens a lot in japan.

 

if you put the whole layout on !-2" thick extruded styrene foam board you can carve away to add your stream or even some depth relief elswhere. helps make things not feel totally flat everywhere on a small layout. the smaller the layout the more creative you have to be to get the eye to focus in on smaller fun details so it does not notice the smaller size. compression of the linear scene helps fool the minds eye into thinking the scene is bigger than it is!

 

cheers

 

jeff

 

jeff

[KenS]

The basic parameters would be the ff - limited to only a 3'x6'(ish) layout, planning on using a Digitrax Zephyr Xtra and to be running 2 trains (maybe 3?) independently at the same time.

 

I guess for starters, it would be the wiring - so I have a few questions:

 

1. While this may be best answered depending on the track layout plan, how does one know where to place power feeders for DCC?

Im a bit confused as some say that in a small layout of 3x6 and having 2 main oval lines - one for the inner and one for the outer is enough, some say to place a feeder every 3'-4'........... while some solder power to every piece of track (hard act to follow).

 

I'm a bit late in replying, but I'll add my thoughts.

 

As Jeff noted, DCC can add some complications for a new layout (mostly in wiring up the decoders in the trains). But aside from that, the Zephyr Xtra is a good fit for this, and could be used to run two trains (you'd need to switch from one to the other by changing the address on the Zephyr, or buy a hand-held throttle like the UT4 (at US$80 it costs more than a DC power pack from Kato though).

 

An alternative to the UT4, if you have an old DC power pack, is to wire the pack to the Zephyr's "Jump Port", where you can use it to control throttle and direction, but not functions like lighting (you can turn those on/off by changing the address on the command station; once they're on, they should remain on). The Zephyr supports up to two Jump Ports, so you could run three trains that way, with two DC power packs.  I'd probably just buy UT4's myself.

 

Cost-wise, DC is going to be much cheaper (maybe half the cost before adding decoders, and a lot less after), even if you buy two DC power packs. But doing DCC will give you familiarity with that technology, and let you add decoders as you buy new trains, which helps spread the cost out compared with trying to convert a dozen trains at once in the future. And as Jeff noted, doing DC first gives you one less thing to deal with (and a first layout has a lot of "things to deal with"). Either works, which you choose comes down to your own preferences.

 

2.  If I badly needed to add more power feeder points to my layout, would a 24-818 Kato Terminal Unijoiners help rather than soldering the track with power wires?

 

I use the terminal unijoiners and they work well.  The big problem is that removing them is hard, because the usual blue tool can't be fit over one of them due to the wire (the plug won't fit through the hole in the tool). These do suffer from the same contact issues as other Unijoiners (see below).

 

Assuming good Unijoiners, you need four track feeders on this layout at a minimum, one on each of the loops, at each end of the oval. These need to have the same "phase" (i.e., make the wire to the track nearest the outside of the table the same color) so that they're in-phase at the crossover. This is the same number of feeders you'd need for DC operation (although you'd probably connect one pair to one power pack for the inner loop and the other pair to a second power pack for the outer loop).

 

The reason for the placement and number is that the crossover breaks the track (inside rails are insulated), so to get power into the sidings, the feeders need to be at the "base" end of the sidings. And when sidings are thrown, they break (insulate) the rails going past them, so there need to be feeders on each side of the siding. You could get away with three feeders, one on each oval at the left end and one just inside the top inner siding, if you only ran trains around that track when the sidings weren't thrown, but I wouldn't do it that way.

 

The crossover insulates the inner rails at all times, so you always need feeders on both sides of it, although with a unbroken oval, one feeder is on both sides.

 

With this, the sidings are unpowered when the switches aren't thrown, so lights on trains will go off.  If you don't want that, add a feeder (same phase as the others) at the base of each siding (i.e., the first unijoiner inside the switch). That would be 8 additional feeders.

 

The length of rail isn't so long that you'd need to worry about voltage loss in the rails, so more feeders aren't an absolute requirement.  However, keep in mind that if you ballast the track, dirt and even glue from the ballast will get inside the unijoiners and increase their resistance. Over time this can cause contact problems and serious voltage loss (visibly slower trains on some sections of the layout). Even with DC this can be problematic, and DCC can be more sensitive.

 

On my layout, which has removable Unitrack, I put feeders every 6' (2m) of track, and tested the joints in between with a multimeter; any Unijoiner at a joint with more than ~3-5 ohms of resistance went in the trash (some joints were still bad after that and I had to trash the track, which had become bent with repeated use).  I had a couple with ~30 ohms, which would have been bad, and perhaps a half-dozen other "bad" ones that probably wouldn't have caused obvious problems, out of perhaps a hundred feet of track. If I have problems in the future, I'll re-do the tests and replace the bad joints, but I don't plan on ever ballasting my Unitrack.

 

The "standard advice" is to solder jumpers across sectional track joints or run feeders to each piece of sectional track, if the track is to be "permanent". If you don't ballast the track, and can easily take it apart to replace a bad Unijoiner, then soldering isn't required.

 

As Jeff notes, soldering to every track is overkill for most situations. And many people build layouts with ballasted track without adding lots of solder joints. If you're willing to tear up the track to fix a bad joint later, this will work under most circumstances, although eventually a joint may go bad due to dirt migrating into it.

 

With just four feeders and a layout this small, you don't need a "track bus".  Just tie the four blue wires together and connect to one output on the Zephyr (e.g., Rail A) and the four white wires together to the other. A track bus is only needed if you have lots of feeders (to simplify wiring) or long distances (to reduce voltage loss).

 

It's possible to get a lot more complicated, with blocks for future occupancy detectors and signaling. I'd advise against doing that. By the time you're ready for that (and can afford it, the cost is substantial) you'll probably have a bunch of other things you want to do differently, and want a new layout anyway.

 

3.  Could I temporarily use the Kato transformer for controlling the Kato switches for the turnouts? (while deciding to elect toggle switches or a digital connection thru Zephyr).

 

Yes.  What controls the switches being thrown is entirely independent of what's on the track for running trains. All you need is a source of 12V DC power that's fairly heavy-duty (the coils have a lot of draw; I think a 1 Amp supply would work, but I don't know for sure) and a on-on momentary-contact DPDT switch (which is what Kato's blue switches are). In electronics catalogs these are often identified as "(on)-(on) DPDT", where the parentheses indicate the "momentary" aspect.  Don't use an ordinary non-momentary switch, as you'll burn out the turnout coil in a matter of seconds.

 

BTW, this thread probably belongs on the Personal Projects board. A moderator could move it...

[macdon]

Thanks for the reply Ken - I appreciate it! 

 

Yes, Jeff is very helpful in guiding me thru the first steps of this journey and I value his advices along with others who have shared their inputs. I also agree that any kind moderator may move this thread elsewhere as I would first venture this via DC and probably later on via DCC.

 

After looking deeper into my proposed track layout, it seems my main consideration to independently run and control 2 trains may have been met already even without using DCC. 

The Amherst 2005 / Manning Oaks which my proposed plan is based upon, is actually 2 ovals (one inner and one outer) joined together by Kato's double crossover.

If indeed that the double crossover is insulated in the middle, then it basically acts like 2 separate tracks when it is close, correct?

The original Amherst / Manning layouts recommends 2 power packs which I have ordered and are enroute, so thats good to go. With these 2 controllers and basically 2 set of tracks, I could independently control and run 2 trains in a single layout. The outer oval could serve as a commuter route, while the inner could be for freight route (since any industrial branch lines are connected to the inner oval anyway).

Another plus is that I could have a friend or family member join in on the fun by controlling any route in the layout. 

 

What I am unsure of, is the scenario of switching the roles of both trains if I open the double crossover since I dont want to add blockages and dpdt switches to control them.

Assuming that both trains are running in the same (clockwise or counter clockwise) direction, opening the double crossover results to a train sharing a single oval currently occupied by another train.

I foresee a lost of power in both trains since both are now sharing a single power pack - as to how big of a percentage the speed drop, I dont know yet.

However, due to the size of the small layout - by the time that a train enters thru the double crossover, the other train would have been in the opposite side of the oval. It may only take a few seconds till it reaches the double crossover and it could be switched to the unoccupied oval thus both trains returning back to their original speed prior to switching.

I could only hope that my assumptions are correct.

 

The Kato turnout switches would be divided by the 2 power packs - any turnout connected to the outer oval will belong to the pack that controls the outer and the same applies with the inner oval / pack.

 

Jeff is right in recommending using DC for starters and consider DCC as a secondary consideration as things could change. In an elaborate one main line and with a desire of running more than 1 train, DCC would be vital. Inobu was also kind enough to give advices on decoder install which I am looking at the biggest hurdle I will need to tackle when going the DCC route, so that is something I could slowly work up to rather than complicate all during the first few steps.

 

Thanks again!

 

Mardon

[macdon]

Here's a youtube video which I assume is the Amherst 2005 plan layout:

 

 

A single power pack with only one feeder - two trains running in 2 ovals.

Although, I cant imagine how he can power both ovals with only 1 power pack and 1 feeder (so he says) using a double crossover thats insulated in the middle.

 

Mardon

[KenS]

The Amherst 2005 / Manning Oaks which my proposed plan is based upon, is actually 2 ovals (one inner and one outer) joined together by Kato's double crossover.

If indeed that the double crossover is insulated in the middle, then it basically acts like 2 separate tracks when it is close, correct?

 

Correct. The "inside" track is always fully isolated from the "outside" track regardless of how the switch is thrown. It's not a power-routing switch. I have some diagrams of Kato switch polarity and isolation on my site, scroll down for the double-crossover one.

 

What I am unsure of, is the scenario of switching the roles of both trains if I open the double crossover since I dont want to add blockages and dpdt switches to control them.

Assuming that both trains are running in the same (clockwise or counter clockwise) direction, opening the double crossover results to a train sharing a single oval currently occupied by another train.

I foresee a lost of power in both trains since both are now sharing a single power pack - as to how big of a percentage the speed drop, I dont know yet.

However, due to the size of the small layout - by the time that a train enters thru the double crossover, the other train would have been in the opposite side of the oval. It may only take a few seconds till it reaches the double crossover and it could be switched to the unoccupied oval thus both trains returning back to their original speed prior to switching.

 

If the two power packs are set to have the same polarity (e.g., a train on either track would be moving clockwise) opening the crossover and having one train cross between ovals only requires setting both throttles to the same value.  I did exactly that many times on my first layout, which was a table-top double-track oval with some interior sidings for a train storage yard. No special wiring or extra switches needed.

 

Note that you don't have one pack feeding power to the other oval, you have each pack feeding the same power to its own oval. The train briefly bridges these when crossing, but that never seemed to hurt my Kato packs (as long at I had both set to the same polarity, otherwise the circuit breaker on the pack trips quite promptly).

 

Doing that simultaneously for two trains is more problematic, as they'd both be controlled by one throttle, so they'd have to be going in one direction, and their speed would be roughly cut in half as the first train crossed into the same oval, and then doubled when the other left it. There's lots of room for things to go wrong there.

 

I avoided that on my layout by using island platforms with loop (double-ended) sidings.  I could park one train on the loop, set the switches to the through route to isolate the siding, then run a second train in via the crossover, take it to the station on  the other side of the layout and park it in that loop, isolate that, then bring the first train out of its siding and across the crossover. But to do that adds lots of sidings you don't have room for.

 

What you could do is have one train park in a siding while the other worked on its track.  Or alternatively you could separate the top and bottom sides of the sidings (giving you a total of four blocks) and use DPDT switches (one per block) to select which power pack was assigned to a given block.  That still wouldn't let you run one train in and one train out, since the crossover would be one one of the two blocks; you'd need three blocks per oval, six total, to pull that off (that's a classic block-wired DC layout, by the way, written up in lots of books).

 

The Kato turnout switches would be divided by the 2 power packs - any turnout connected to the outer oval will belong to the pack that controls the outer and the same applies with the inner oval / pack.

 

You could put all the switches on one pack if you want (I did).  They don't draw any power when off, so there's no real limit to the number per pack, and no dependency that track power comes from the same pack as switch control power.  You shouldn't throw more than one per pack at a time, but that's not a big limitation.

 

If you plan to have multiple operators, then putting the "outside" switches on the "outside" pack will be easier for people to keep straight, and reduce the risk of someone throwing a switch underneath someone else's train.

[macdon]

Thanks Ken - noted.

 

Mardon