I decided to tear down my old layout that I had been working on for about 10 years. Even though I had been working on it for 10 years, I had very little to show for it. I was never really happy with the design, since it just kind of evolved from a few basic sketches.
While reading one of the various model railroad forums, I stumbled across a post about XtrkCad being made available for free download. I downloaded it, and started playing around with it. Next thing I knew, I was well on my way to designing a new layout.
Well, I've finally made it to another major milestone. Last weekend on March 18th, the "silver screw" was driven to commemorate the completion of major benchwork construction!!! All the benchwork is now in place for both the main and upper levels, as well as all the subroadbed for all the mainline grades. There are still two small sections of subroadbed to be completed for the two branchlines.
A few modifications have been made to the trackplan along the way, but it has been a great help to have a complete plan before starting.
The series of pictures below shows all the benchwork in the order you see it as you walk through the layout space.
The large gap in the subroadbed in the third and fourth pictures will be spanned by a Grandt Line truss bridge.
The area around the mine from the old layout is one of the areas where the trackplan has been modified. In order to accomodate the new track arrangement, a small extension needed to be added to the existing shelf. This is the only area of the layout that uses Homasote for the subroadbed.
The upper deck is starting to go in using the same L-girder technique as used for the lower level. The only difference is that the L-girders for the upper level are made out of two 1"x2"s glued and screwed together instead of a single 2"x3".
The subroadbed for the mainline is also in place from the duckunder back to where is crosses under itself.
Another year has gone by. Sometimes I wish progress was faster, but as long as it's fun, that's all that matters.
Over the Christmas holiday, the remaining subroadbed for the main yard was completed, along with the mainline loop around the helix. (Here's what the helix looked like before the mainline loop.) This allows the mainline to climb from the yard to the narrow shelf along the wall that represents the only part of the old layout to survive. This loop will also carry the branchline, which will split from the mainline behind the helix, and return towards the yard. The grade past the mine (again, part of the old layout), was also adjusted to be slightly shallower. The main girders for the upper level are now starting to go in.
Once the mainline loop around the helix was completed, I was able to go back and check the aisleway spacing. I'm using 24" wide aisles so I could maximize the amount of layout space (a bit tight, but I'm usually the only operator, so it should be fine). When I checked the width, it was quite wide in one of the corners for the main yard. I though about leaving it, but this is a critical spot, as it's where the yard starts to curve, and after laying out a mock-up of the yard, it was too tight. It was a bit of work to patch together enough pieces to "fill in" the corner, but it will be worth it, since the yard will now have a much smoother curve.
I use a piece of flexible moulding to define the front edge of the layout. The moulding is some sort of plastic, and works great for making large, sweeping curves. It's availble at most home improvement stores, in the same section as the wood moulding.
Well, it's been just over a year since I started the rebuilding. The progress is modest by some standards, but I have gotten a lot accomplished since I got back to the layout since. One of the big accomplishments is that there's now some visible trackage. I have also started laying out the main yard, and have gotten the partition wall built and painted between the layout and the laundry area. You can see the wall on the right in the first picture below.
One of the things I had to go back and redo was the placement of the staging yard ladder. When it was first laid out, the goal was to maximize the length of each yard track. However, as the main-level benchwork progressed, I realized that the ladder was going to be "burried" deep in the benchwork. Fortunately, only one turnout was in place, so it was relatively easy to move.
This is the first time I'm using caulk to "glue" the track in place, and I was a bit concerned about having to relocate tracks that were alread in place, but it turned out to be no big deal.
One of the other firsts on this layout is the use of superelevation on all the visible mainline curves. I use thin strips of duct tape under the out rail built up to 6 layers thick. Transitions are handled by having each successive layer offset by about 2" from the previous one. The transitions are started prior to entering the curve. IMHO, it's a subtle, but worthwile effect.
Well, not much progress has happened over the summer, but I've finally been able to get to the layout over the last few weeks. Work continues on the end of the staging yard opposite the helix. The transition from the staging yard to the main level is now complete.
These closeups show the details of the benchwork construction for the main level: L-girders built with 2x3s for the main beam, and 1x3s for the caps, and 1x2s for the stringers. The subroad be is 1/4" plywood laminated with 1" rigid foam. 1/2" plywood is used where the plywood is joined. The joints between the plywood and the foam are staggered for added strength.
Now that the main helx is done, work has started on the other end of the staging yard. For now, just run one track is through the staging yard in order to get the turnouts set on each end. Once the yard is complete there will be six tracks.
At the other end, the track rises from the staging level, on an elongated helix. When it's complete, it will have two loops. This end uses standard L-girder construction.
It's finished!!! The helix is finally complete!!!
I changed the geometry a bit and ended up only putting in 5 loops. That increased the grade to about 2.7%, but so far, my tesing has showed that this will not be a problem for the type of trains I plan to run (18-25 cars with 2-3 units). The beauty of the threaded rod system is that if it does cause problems down the road, it's pretty easy to add an additional loop and reset the grade.
I've added a few detail shots of the threaded rod system, the camper tape I used for roadbed, and the transition from the foam in the staging yard to the plywood for the helix.
All in all, I'm pretty happy with how the helix turned out. It was a lot of work get get all the pieces cut and laminated, but I ended up with very little waste, and was able to maximize the separation between each loop. I like the octagon system much better than cutting semi-circles, and I will probably use it in other places around the layout.
All of the main benchwork is now finished, and I've started to work on the helix. The first loop is already in place. The track radius is 29", and there will be six complete loops. The top of the helix will connect where the level is sitting in the photo below. The total rise is about 25", so the grade works out to be about 2.3%. I wanted the helix to be a little larger, but there are two other tracks that have to snake between it and the back wall.
The helix is constructed using the "octagon" method. This method uses eight straight sections to build an octagon. The track radius is then inscribed inside the octagon. There is very little waste using this method, but it does require a bit of geometry and trigonometry to figure out the dimmensions. However, once the dimensions get figured out for one segment, you can make a template to cut all the remaining pieces. Once I ran all the numbers, I drew it in XtrkCad and laid out one complete loop just to make sure that everything worked. I'm glad I did, because it showed me that I had made a few math errors!
My helix has a couple of additional "features". First, since I have a few tracks that will wrap around the outside of the helix, I had to clip the outermost "points" off the octagon to get everything to fit. Second, I wanted to maximize the spacing between levels, so instead of splicing each of the segments together using 1/4" or 1/2" plywood, I decided to build it as one continuous lamination using two layers of 1/4" plywood. This way, there are no slpice plates hanging down from the main deck, and the thickness of the subroadbed is 1/2" all the way around. One layer is offset from the other by 1/16th of a turn. What I ended up with are two templates that look like like this.
These templates are then used to cut the actual helix pieces. I take 4'x8' sheets of 1/4" plywood and rip them into 4' lengths using a circular saw and straight edge. The width of the upper template is about 6" and the width of the lower template is about 9 1/2". The length of both templates is such that two pieces can be cut from each 4' length. All of the angles are then cut on my sliding compound mitre saw. 8 pieces of each shape are needed for one full loop. That's about 100 pieces for the total helix!!!
The laminations are built up using yellow carpenters glue. Pieces are glued together and a bunch of weight is stacked on top (a few full cases of beer) and left to dry overnight. Once a half loop is built up, it is "installed" into the helix.
The helix is supported off the main benchwork using 3/8" threaded rod. Now that I've tried it, I can say that it's the only way to go. It gives infinite adjustability in setting the grade and getting everything level. I set the grade using a 12" combination square by separating it into two pieces. Each end of the ruler is placed on the centerline of the track, and a drill bit is placed under the "downhill" end, and the level is placed on top of the ruler. The nuts on the threaded rod are then adjusted until the bubble reads level.
Lots of progress. The old layout was traditional L-girders with a plywood and Homasote sub-base. The new layout will keep the L-girders, but use 1” extruded foam in place of the plywood/homasote.
You can see the portion of the old layout over the water meter that will become part of the new layout, as well as all the lumber from the old layout.
One of the big reasons to deal with the “issues” of the old layout was to motivate me to actually work on the layout. The limitations of the old layout were always haunting me, and every time I went to work on it, I felt like I was fighting a losing battle. Well, I’ve done more in the last week-and-a-half, than I’ve done in the last year-and-a-half!
I contemplated trying to just “fix” the old layout by reworking sections of it to get it to resemble the new plan, but in the end, I decided it would be much easier to completely tear it down and start over. So, over the long Thanksgiving weekend of 2005, I started tearing out the old layout. Within a few days it was completely gone, and I started rebuilding. All that was saved from the old layout was a portion of the backdrop and a small corner section over the water meter.
One of the things missing on the old layout was any sort of staging. The new layout keeps the same two-level idea from the old layout, but adds a staging level below the lower level. All three levels can be seen in this photo.
These are the only photos I have of the old layout. These photos are a little dated, but not much more progress ever happened beyond what was in these pictures.
