• The Inner Loop
• The Outer Loop
• The Upper Loop
• Clearances
• Turnout and Cab Controls
• DCC
• Drawing Notes

This is a diagram of the inner line of the GIRR Mountain Division. Track in dotted lines is hidden. The elevation of the inner line ranges between 50" and 59" from the floor.

The trolley line is flex track bent to a 1' radius. The Bachmann trolley can deal with this radius, barely anyway. Trolley control can be either fully automatic or manual. The trolley makes two timed stops in town with controlled deceleration and acceleration and then makes a much longer (up to 5 minute) stop in the hidden section. The reversing loops are one way with spring switches.

The maximum grade on the inner line is 4.2% which restricts train length to an average of 4 or 5 cars. Curves are almost all 2' radius with one section at 2.5'.

The track is a combination of LGB sectional and flex track and Aristo sectional track. As far as I can tell, the two types are functionally interchangeable. Being indoors, track cleaning is required maybe once a year since all the wheels are metal from San-Val. Turnouts are all 1200 type with all of the left turnouts being LGB and most of the right turnouts being Aristo. This is just an artifact of what was available at San-Val the day that I bought much of the track.

This is the outer or main line which is wrapped around the room. Most of this line is about 9" to 12" above the inner line (59" to 62" from the floor) except at the interchange where the inner line rises to meet the outer line. The interchange track is split between the inner and outer line drawings at the lower center of the drawings.

Grades on the outer line are 1.5% maximum with most curves being 2' radius. Train lengths can exceed 20 cars with the limiting factor being train straightening in the curves.

This is the upper line. It connects to the other two lines at the interchange and then climbs a 1 3/4 turn spiral inside the mountain. This puts it 77" from the floor so that a stepladder is required to view this level. The mountain is hollow with clear access inside to all the hidden track. The loop at the other end also has access from inside the loop.

The reversing loops are conventional one way loops with spring switches. Reversing control on the loops is handled by a home-brew intelligent auto reversing controller which senses train presence at the exit of the loops and determines if the main line should be reversed or not.

The grade in the spiral is 5.2% on a 4' diameter curve. This restricts train length on this grade. A Bachmann 2-4-2 will barely handle one car, a weighted Big Hauler will handle 3, an LGB 0-4-0 with a powered tender will handle 5, and the Shay will handle 8.

Clearances to walls and other obstructions are tight. I designed it to clear a Big Hauler, the largest engine that I envisioned using. This vision turned out to be myopic as I've had to make adjustments over the years for larger equipment. However, with the exception of vertical clearance, the Shay did fit with only very minor adjustments. The Bachmann Heisler required some more minor tweaks. My hard vertical clearance limit is 7 1/4" from the rail head and the Shays weren't close to that. I replaced the stacks (with ones ripped off old RC Big Haulers) and cut a 1/4" sections out of the middle of the steam domes to make them fit. If your layout will clear a Big Hauler, it can probably clear a Shay.

Turnouts in both yards and the interchange are each controlled by interlocking route control systems such that only one control panel switch is thrown to align all the turnouts to set up a complete route through that particular trackwork. In the interchange, up to ten turnouts are thrown with one command. This system has practically eliminated derailments due to misaligned turnouts and I rarely find a need to check the aspect of any turnouts.

In the yards, power is also automatically routed to the selected track. In the interchange, power control is automatically transferred between power packs so that control is continuous throughout the trackwork. When the lines are not interconnected, each line has its own power pack. When lines are interconnected, there is a hierarchy which defines which pack takes over control of which line. The outer power pack (or TE, switch selectable) is the master pack. The inner pack (or its associated TE RX) is the 2nd in the pecking order. The upper loop runs from either the outer or inner pack depending on the state of the interchange. When the upper loop is not connected to either other loop, it runs from an MRC power pack.

The main yard normally runs from the outer loop power. However, there is a yard power switch that can run the yard from an LGB starter set power pack. There is also a "yardmaster" switch that allows the main line within the yard limits to be hijacked by the yard power pack.

This arrangement sets up a conventional cab control system with 4 cabs, all of them capable of running a portion of the layout independently.

Even thought this layout is small, I use an Aristo Train Engineer on the main (outer) and inner power packs. I find that the freedom to walk around with a train really enhances operational enjoyment. I haven't yet connected the Train Engineer to the interlocking control system (as I have done in my outdoor layout) but I might later.

I am in the process of converting the GIRR Mountain Division to DCC. I converted the GIRR outdoor layout to DCC about 10 years ago and the converstion has been completely successful once I settled on the right decoders. I was pleased enough with the long term results that I elected to spend about $1100 on the DCC equipment and the decoders for the locomotives. About half of that was for the fixed equipment and half for the DCC decoders I needed for my existing locomotives. I could have saved $200 by not getting the walkaround radio control option, but this feature is important to me. Additional DCC costs will be about $50 per new locomotive or $150 if the decoder includes sound.

I purchased the same Digitrax equipment (radio equipped Super Chief) to install on the indoor layout primarily because:

1. It worked
2. I understand it and know how to use it
3. It's less costly than other major DCC systems, especially the European ones
4. It has walkaround radio control
5. I retain equipment interchangeability with the GIRR

The addition of DCC presents only a little additional wiring complexity. Since I will retain the complete functionality of the cab control system, I have to add some switches on the control panel to insert DCC. These switches will select between the DCC source or the existing power source for each of the three loops. The main yard will automatically accept the DCC track signal from the outer loop and the yardmaster function will still work as before.

A piece of track should be designated as a "programming" track for initial DCC decoder programming. On the GIRR, I use a separate 3' section of track that I pull out of the control cabinet and set on the ground when I need it. On the Mtn Div, I use the track that runs right in front of the control panels. It is already double gapped at both ends and yet another DPDT switch is used to connect it either to it's normal source of power or the programming track terminals of the DCC booster.

The inner loop has two reversing loops that are now wired as X-sections. A portion of each loop has it's track polarity reversed by a turnout at one end of the section when it is being used for reversing. Currently, a train is driven onto the those sections from one end or the other and stopped. If the turnout that was thrown to get onto that track section is the turnout that controls the polarity, it is switched back. If the train was driven on at the other end, the polarity control turnout is then switched to allow the train to exit. Then the power pack polarity is reversed and the train is driven off the other end. This operation requires manual intervention but it is cheap and easy so it will be retained for the DCC conversion. The only operational difference is that with DCC, the train doesn't have to stop, the polarity controlling turnout can be thrown on the fly. These reversing sections are not used all that often so that manual intervention is acceptable here.

The upper loop is another story. The automatic reversing system in use there assumes DC or PWC on the track. DCC on the the track will totally confuse it. Therefore I switch the existing reversing controller off with an existing switch and switch in (with the same switch) a DCC autoreversing module to power the two loops. The two loops would normally run from a bridge rectifier to make the polarity in the loops constant. This cannot work with DCC, hence the need to switch in the autoreversing module. Doing it this way, I can have a DCC converted loco running continuously loop to loop, or an regular track powered loco running loop to loop, or a DCC equipped but analog converted loco running loop to loop.

On the GIRR outdoor DCC layout, I run a fairly high track voltage of 22 volts to provide the speed and power that the larger heavier locos need. The Mtn Div is a slower, calmer, railroad that won't need to run as fast and the loco loads will not be nearly so high. I therefore don't need the very high current booster that I use outdoors and I can run the track at lower voltage, about 16 volts. This limits the top speed of the locos. It also allows me to use some less expensive HO sized DCC decoders on some of the lower current draw equipment.

The layout is already converted and running with excellent results and much of the equipment has been converted as well. Where they exist, sound systems are generally being retained. In two cases, a combo motor/sound decoder is being installed where the sound was non-existant or of marginal quality as these systems are usually less expensive that a good digital stand alone sound system. The following table lists the equipment converted and what went into it. It is primarily for my reference in the future, I find that these web pages are a good a place as any to record what I did.

I've received some questions about how I created these drawings. I used MacDraw Pro on a Macintosh (mostly done on PowerBook 100) to create these drawings. I drew custom track templates for sectional track and copied and moved them around as necessary. Track elements lock on a 0.5 cm grid (the drawings are metric) so lining up things is easy.

The rest of the drawings were done with the MacDraw Pro drawing elements on a 0.5 cm grid. All basement measurements were made very accurately and even some non-square corners are handled properly. The drawings include about 200 individual layers that can be stacked and shown in any order. These layers include the basement, plumbing, house framing where important, blocked or restricted access areas, layout framing, layout roadbed, track, equipment clearances, wiring, structures, significant scenic elements, wiring diagrams, operational notes, in short, everything significant

Doing the drawings with CAD was a real boost as they came out so accurately. I could cut wood and track by the numbers and fully expect them to fit.

I subsequently tried to use CadRail (my PowerMac does Windows too) to do my outdoor layout and had to give it up. The program was inflexible, frustrating and didn't allow me to add the other associated graphics as I wanted.

I did use Design Your Own Railroad to do operational tests. As a CAD tool DYOR is fully useless, but it does do a credible job in testing how a layout will work operationally and it helped me refine my plans while it was easy.

Eventually all good software dies from bit rot. It's not that the software actually changed, but it's environment does. MacDraw Pro ran on the "classic" version of the Macintosh OS (up through OS 9) and later in the classic mode in OS X (10.0 through 10.4). However, in Mac OS 10.5, support for the classic OS was dropped and MacDraw Pro would no longer run. I have converted to another program called EasyDraw. EasyDraw will read and convert most of a MacDraw Pro drawings however the conversion sometimes isn't perfect and some manual tweaking is required after the fact. Also, EasyDraw isn't as easy to use as MacDraw Pro. It seems to take more mouse clicks to get anything done. Sometimes it is hard to remember where the authors of the software stashed some needed command and it also has some "interesting" software quirks. It has much more capability than MacDraw Pro but this extra capability comes at the cost of extra complexity.