I revised the Decision Matrix. I realized that the matrix ratings of 0-3 really didn't give enough granularity to discriminate between options. For example, Option A (the Fredericksburg extension) would be harder to builder than B (Falmouth extension) but both were getting the same score. So I adopted a 1-10 scale for ratings. In case of numerical parameters, like length of mainline, I was able to use this to score the ratings in proportion to their actual values. But most of the others are subjective ratings.
Also, I realized that I was using the "manageable" rating to cover two different aspects - ease of construction and maintenance requirements. Construction difficulty is not as big an issue to me as maintenance. So I broke that into two categories.
I also felt that I should have a category for open country running. My favorite scene on the existing layout is at Wielepp's cut, which is just a single track cutting through the country side. So I added country running as a rating.
Revised version C |
What if I shortened the Stonemans-Falmouth peninsula by 2 feet, while at the same time eliminated the wye at the lower left. That opens up some space so I could fit the couch and a TV in that corner of the room with at least three feet of clearance to the turn-back loop. I traverse this aisle numerous times a day, so keeping the aisle here wide is a bonus.
For added wow-factor, I added a 4 or 5 foot long trestle to the central peninsula between Stonemans and Falmouth. That helps compensate a bit for the lack of the big bridge at Fredericksburg.
This plan shows a full Burnside Wharf in the Home Office. But that is a future add on that might not happen. In the meantime, the siding in the far lower left corner is the Burnside Wharf set-up track. it provides some but not all the functionality of the actual Burnside Wharf. If I wanted to go all in, then I would build the Burnside Wharf shown here. The engine house would help disguise the hole in the backdrop.
Another thought occurred to me with regard to the double deck layout. One of the things I did not like about the previous double deck plan is that I would have to rebuild most of the layout in the front room to make it climb the required height, not to mention my wife freaking out about cutting through the stairwell.
What about a double deck version of Option C? If I started with Option C, and put a grade on the central peninsula, it could climb above Aquia Landing. The peninsula has about 40 feet of run. At 2% the track would climb about 9.5 inches. If I also dropped the approach to Aquia Landing, that could get about 2 to 3 inches down. That could create a deck separation of 14-15 inches between a lower and upper deck. I would need the maximum length peninsula, so the crew rest area is more cramped than Option C.
Partial double deck plan with 230 feet of mainline run, but another 30 feet of hidden hard-to-access track. |
Aquia Landing is one of the most importance scenes on the layout. Why ruin it with a track running across it in the sky?
It might be possible to move the upper track behind the backdrop at Aquia Landing by moving the wharf out 4 inches, and putting the upper level on a narrow shelf (see plan at the left). This creates a long stretch of hard-to-reach hidden track. The extra hidden portion could be on a grade. Thus, the overall grade from Stonemans to the end of the hidden section is less than 2%. That's a good thing, but I'm not sure the extra 50 feet of main line run is enough compensation for the drawbacks of the hidden run, somewhat cramped access at Falmouth near the workbench, and the extra complexity.
After all this machination, it's still a very close thing. Option C is starting to look like the best option both in numerical ratings and my gut feel. In addition, it gets CINCHOUSE (aka as my wife) approval. It is also interesting to note the the PoLA expansion moved up in sum of ratings, but got surpassed by the O scale Maine Central branch when priorities were factored in. PoLA as rated in this chart loses a lot of points for complexity as it has below grade staging and a section of CTC. A simplified version of PoLA with open staging and not CTC would score a lot higher.
This weekend, Leighton Moreland stopped by to visit the layout. I met Leighton at Caboose Hobbies last year when I visited the new store. He was in town before starting a new job as a civil engineer building bridges. He models in HO and O. He liked the PoLA layout, but really loved the O scale layout. I showed him the paper mock up of the Rappahannock River bridge and he liked it. Don't tell him I might not build it. We tried running some of the BNSF diesels on PoLA, but as usual we could only get one to work due to fracking DCC glitches. However, we did run the Aquia Line and it worked flawlessly. Score another one for the Aquia Line!
C could have some additional crew space near Stare’s tunnel, maybe?
ReplyDeleteLike this version a lot.
When do we start building?
Is there a decision yet?
ReplyDeleteNot final yet. I am targeting Dec of this year as the start date for the major rebuild.
Delete