Hello!
I thought to start a discussion on free-standing benchwork as I'm trying to figure out the best approach for my setup.
Most people are blessed to hang their layouts on the walls, but I only have 2.5 walls and a big open space with two columns. More details on that are in my other thread at http://cs.trains.com/mrr/f/11/t/260185.aspx
A basic sketch for a self supported peninsula looks like this:
It's a mish-mash of things I've seen elsewhere incorporated into one.
I gathered the materials, a combination of plywood (3/4" aspen) and dimensional lumber (2x4, 2x3, 2x6)
Already a lesson learned: don't use Aspen plywood - it is way too soft for basic open framework and if you are not careful with the spade bit you get a mess like in the photo below.Aspen would probably do well for a tabletop, being soft you can drive rail spikes into it, etc.
Progress on the way...
Larger module is 30" deep, smaller is 24". Intention is to test the depth against the height of double-decked setup and see what works the best in this space
Here, H0 scale track is on the left on the 30" module; N scale track on the right on the 24" module. I hate to say it, but I could fit a whole lot of N scale track into 24" depth.
Still need to build the upper deck portions for this test. An 18" deep shelf to go along with the 30" module below it, and a 12" deep shelf for the 24" module.
More to come, soonish...
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That is really a unique approach to layout building. With the "feet" narrower than the modeling area I would be concerned about one side being heavier than the other and the chance of the whole structure falling to the heavier side. A soloution to your spade bit problem, stop drilling as soon as the point of the spade bit breaks thru the material. Turn the board over and finish the hole. Please keep us up to date on your progress.
Good point on the spade bit.
If lateral balance might be problematical, simply attach a box of rocks (or scrap metal) to the most lightly loaded horizontal leg. Where, and how much weight, can be determined by hoisting each leg with a spring balance.
Going by my own experience, any tendency for the box frames to deflect out of square can be permanently stopped by adding one diagonal element to the frame. I used a small steel girder, but could have achieved the same result with a length of baling wire.
Chuck (Modeling Centeral Japan in September, 1964)
Made a bit more progress today...
The left side is the 30" and 18" deep tabletops, at 40" and 59" respectively off the floor.
A (hard to see in the photo) 60' box car is sitting on the H0 flex track on the main level, looking kinda big to me, in relation to the size of the module surface and the size of the room.
Sigh, a few of these cars and they'd fill the 6' length of the module...
Similarly, on the right side a 24" and 12" deep tabletops, at 42" and 58" respectively off the floor.
An (even harder to see in the photo) box car is positioned on a section of Kato N scale track, both looking miniscule and teasing at the amount of railroading that would fit in 24" depth.
Main levels have 1/2" plywood on them, while upper levels are made with 3/4" plywood resting on common shelf brackets. This combination should offer enough clearance between levels without taking away vertical space.
Also to consider is that because there's no open-frame benchwork on the upper levels, wiring will have to be done more creatively as well as mounting of the lighting system for the main level.
I used clamps for all instead of permanently affixing with screws so that the various surfaces could be moved up or down and test how heights impact visibility of levels.
In both cases at my eye level of 71" I can see all the way to the inner edge of the main level without obstruction from the upper level.
Since fascia is missing on all of the outer edges, I surmise once in place it would probably cause some interference in viewing all the way to the inner edge.
By moving away half, or full, step back into the aisle remedies that interference though.
Some mistakes in design/construction have been made:
- Because it is free-standing, the studs are only anchored at the bottom of the feet, while the top of the stud can swing somewhat forward/backward.
- The inner grid spacing of 2x3s between the studs does not align to the open-frame benchwork crosses. Consequently, the gassets can not be mounted to level and secure the benchwork. This spacing needs to be somehow standardized.
- The choice of wood used for the open-frame benchwork seems to be an issue. Aspen is soft kind of wood and might not be providing sufficient rigidity.Originally, it seemed that ripping a 4'x8' plywood sheet might have been more cost effective than buying dimensional lumber (Pine), but in retrospect the added rigidity of the latter and it light weight could offset minor additional costs.
The experiment continues.
For thin lighting, consider LED strips. They are available in different white color temperatures (warm white, cool white, etc) as well as colors and also RGB. My intention is to use two white strips plus an RGB strip and maybe a blue strip to light each level. That should give me a nice bright daylight, as well as allo dusk adn dawn sequences plus night operation (the blue ones). These have been around long enough now that the technology is mature, the products are reasonably priced, and they work. The ones I put under the bottom shelf of my electronics workbench - well, the adhesive backing said it was genuine 3M, but I don't trust it. On Amazon I found shallow U shaped rubbery mounts, they fit over the LED tape and have 2 screw holes. They produce quite a bit of light. On 18 to 24" wide benchwork, a double strip whould minimize false shadows and make enough light to read car numbers. The RGB strip tuned to white menas there would actually be 3 white strips during day operation. One blue strip plus the RGB strip on blue should be sufficient for night ops - cheap pen lights with uncoupling picks attached will allow operators to see what they are doing.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
A book that might be of interest
https://www.amazon.com/TilTable-Book-Tables-Model-Railroad/dp/0983579008?SubscriptionId=1NNRF7QZ418V218YP1R2&tag=bookfinder-test-a-20&linkCode=xm2&camp=2025&creative=165953&creativeASIN=0983579008&tag=bookfinder-test-a-20
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
@rrinker
That's what I was planning to do - already ordered some LED strips to do a test.
I ordered Warm and Cool White, and a Blue, so I will do 4 rows of LEDs. Top will be Cool+Warm and side will be Warm+Blue. I also ordered dimmers for them so that they can be well adjusted.
Ultimately I would go with several rows of RGB as those LEDs can be individually addressed and controlled. Think rolling day/night across the layout. Ok, might not look as great in my layout size but still...
@DSchmitt
Thanks for the pointer, will check it out.
The RGB set I have - the coontroller is junk, it doesn't allow enough brightness options for each color. The steps are very noticeable. I've decided to just build my own which will allow more gradual transitions between colors.
On a previous layout I mixed warm white and cool white flourescent tubes (2 tube fixtures, each got one of each type) and while looking up at the lights was very odd, the light it cast on the layout surface was actually pretty good. So a strip of each type LED may be a good option. The ones I have on my workbench use 5630 LEDs, they are brighter than the ones that use 5050 LEDs. The RGB strip I'm pretty sure is 5050 size LEDs.
It's not clear from the pictures, but are your modules held to the uprights only by screws through the rear girder? There's going to be a lot of downward torque at the outer edges of the layout once fully loaded and especially if someone leans against it. I'd be a bit concerned about the layout drooping without either legs or a diagonal supporting the outer edge.
jim
jmbjmbIt's not clear from the pictures, but are your modules held to the uprights only by screws through the rear girder? There's going to be a lot of downward torque at the outer edges of the layout once fully loaded and especially if someone leans against it. I'd be a bit concerned about the layout drooping without either legs or a diagonal supporting the outer edge. jim
Actually they were supposed to be held with gassets, but because the stud spacing does not match the spacing of the open-grid joists I will have to re-engineer it in the next iteration.
It's a bit difficult trying to match the spacing on both pieces across large spans, without some very precisely cut wood pieces. Maybe I can get IKEA to start mass producing these which would make it easier. :D
No need to overbuild. The whole point of keeping the benchwork narrow is that you can easily reach WITHOUT having to climb on it. No need for gussets every wall stuf. An occasioonal diagonal brace from a stud tot he front edge will work, at other locations some metal L pieces will sufficiently reinforce the attachment to the wall and don't have to necessarily line up with the benchwork crosspieces. And as long as you aren't planning to build scenery with concrete, modern scenery materials are pretty mightweight.
Lee
rrinkerAn occasioonal diagonal brace from a stud tot he front edge will work
I have done this myself and found it not to be sufficiently rigid. The problem is that the "stud" in this wall you have built will bend in the wind like the tree it was cut from. I tried several ways to fix this, but in the end I had to attach to the ceiling to keep it from moving.
rrinkerAnd as long as you aren't planning to build scenery with concrete, modern scenery materials are pretty mightweight.
Far too much emphasis is placed on the weight of the layout and what's required to support it. Supporting the weight is not the primary concern. What's important is stability. The penninsula needs to built so that when someone bumps into it, it doesn't move. Otherwise a small "hip check" into the benchwork will derail every car on both levels of the penninsula.
Another under building issue that often comes up is the size of subroadbed and the spacing between risers. Your subroadbed is going to sag between the risers over time. Any sagging is going to look bad, and the smaller your scale the worse the sag will look. A 1/4" sag is 3 feet in N-scale. Your models will end up looking less like trains on track and more like boats on the ocean.
You do in fact need to overbuild - by a lot.
I have the right to remain silent. By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.
On that 6' length he builkt, if it has just TWO diagonals fromt he front edge back to the vertical studs near the base, the only thing that will happen with excessive weight is the whole thing might tip over. That can be fixed by making the 'feet' longer. Those are 2x4's vertical, they are not going to deflect. My electroncis bench has 2 - a whole 2, 2x4's - the wrong way - the 4" side facing front, holding up metal shelf track with 2 brackets for each shelf. Those verticals each have 2 bolts, one near the bottom of the leg it extends above, and one near the top of the same leg. I have some heavy equipment like power supplies on those shelves - the only deflection is the middle of the shelf, it's one of those standard shelf pieces you buy at the store, less than 1/2" thick. The vertical 2x4's, even though they are oriented the wrong way for minimal deflection, don't move.
My previous layout,t he individual sections, even the ones that were 2x8 ft, standing alone in the middle of the room, on the carpet, were kind of wobbly. Integrate them intot he other modules running around the walls, and it was solid as a rock. The only place I needed to do anythign extra was one section that was completely standalone - with a liftout section on either side. That one was wobbly all the time, so I used a pair of 90 degree metal brackets and screwed it to the wall studs in 2 places. No more problems, even when I bashed my head (more than once) on the liftout because I didn't feel like taking it out and ducked under (or almost under) instead. I think one boxcar derailed, once.
That's perhaps one of the reaosns I'm not a big fan of L-girder - the hortizontal support is a screw run up throught he narrow flange of the girder into the narrow edge oc a 1x4 joist. Except where there are legs so the legs extend up and can be fastened to the wide part of the 1x4. That to me sounds liek it will be VERY wobbly. Box type construction, there's nothing to twist, with the cross pieces butted inside the logitudinal members. Brace the legs, and there's no wobble, with a little weight on the thing.
I revently tossed a layout I built some 37 years ago. 3x6 N scale, 1/2" plywood on top of a 1x3 box frame that has a whole 3 cross members. 2' on center. Even after years in a damp basement - no sags. Even with a heavy hydrocal over chicken wire mountain at one end, that end did not sag. No one wanted it, and I got rid of all my N scale years ago, so it got cut up with a Sawzall and tossed in a dumpster - though I later found a tunnel portal that fell off so I kept that as a momento. For the 3 or 4 years I had it up and running, it sat on 2 sawhorses. That's it. No legs. It didn't sag. No, you could not body check it or all the trains would fall off. But if someone is running around my layout body checking it, I'm going to body check them right out the door and down the driveway. The club modular (sectional, really) layout is much the same way. Individual sections with their legs (many have no braces - just 2x2's that sit in pockets on each corner) are VERY wobbly. Put it all together and it's pretty sturdy. Also not going to take a solid body check without knocking stuff over - but it's a model railroad, not a tackling dummy. Even on public display, there is very little jostling of the layout. I've never had any of my equipment knocked off the track.
Overbuilding doesn;t always save you - Some 20 years ago I belonged to the L&KV club that was in MR not too long ago. At our old location. No AC in summer (very hot and humid). The layout was built with nothing smaller than a 2x4, with more support than is usually found in a house wall, even a load bearing one. Very heavy duty (which is why the landlord thought he had us over a barrel when he tried to quadruple the rent upon lease renewal - he forgot about the existence of Sawzalls, I guess). But this one whole end, built over the summer - once winter came and the heat turned on (we had plenty of heat) - the wood all dried out in the hot, now dry, air and stuff twisted and buckeled all over that end of the layout. All the track and subroadbed around that turnback curve had to be removed and redone. And that was a layout that if you hip checked it, you were going to the hospital with a broken hip. An elephant could have walked on that layout.
I think I've seen a photo of the X legs somewhere, can't remember where. I'm just not sure it would work for a multi-deck peninsula I plan to build. As the current plan is a G the peninsula is pretty narrow at places so X legs won't have enough space unless I let them extend into the aisle.
Also, I'm going side with carl425 on the need to overbuild.
Last week I was at my local club, talking to two other members about building benchwork. All three of us were leaning on the layout. It was not intentional, it just happened, almost as a matter of habit or convenience.The benchwork there is pretty solid, so it just stood there without moving. But I can imagine if it wasn't...
I can see it, especially in N Scale, a hip check on any part of the benchwork that's not robust will topple all rolling stock in that area like dominos.
Regarding my test build, the verticals are 2x3, while the legs are 2x4s.
@rrinker, let's see your electronics bench? :)I built mine many years ago; 2x4s, survived a move, disassembly, re-assembly, feels like it's built like a tank. Still need to finish setting everyting up, but because I haven't done much electronics lately I feel I'm stuck in the past decade with the equipment I have.
What I still have packed away is an ERSA IR/PL550 BGA rework station, and a full PACE PRC 2000 soldering station.
rrinkerThat to me sounds liek it will be VERY wobbly.
Turns out, it's not. The cookie-cutter roadbed makes a big difference -- the benchwork just gets stiffer and stiffer as you go. L-girder is fine, open-grid is fine -- but if you've never actually built with L-girder, you'd be surprised how well it works..
Layout Design GalleryLayout Design Special Interest Group
Also built like a tank - all 2x4's and a solid core door top. I have another section that will come off in an L shape on the right to be my train workbench.
This is before my static mat came, plus since I built this about a year ago, I have aquired another power supply and 2 more bench DMMs. And not shown are my Fluke 8060a handheld or my EEVBlog Bryman BM235 handheld, or my Fluke 8012a bench meter. Oh and the monitor for the computer is now on an articulating arm to save bench space. There are LED strips under the bottom shelf to light the surface. The shelves just sit on standard brackets, so they come off, the verticals bold to the bottom frame, and the top is held on with 4 L brackets screwed in underneath, so it all comes apart to move - the door is quite heavy though.
I actually drew it all in 3rd PlanIt before I built it.
Very nice, I really like your main surface, looks like a solid piece of wood, and how you used the shelf brackets to hold the three levels that tie into your bench studs.
I made my surface out of two pieces actually: subsurface is pine planks, while the top is hardboard/masonite. I knew top surface would get messed up over time so I made it replaceable. All I have to do is plop the plastic edge off the bench and replace the surface.
I put the LED strip as well, under the first level to light up the main bench area. My LEDs are mounted on a metal bar that swivels so I can adjust the angle they shine at.
To think that I designed and built this bench while living a two bedroom apartment, cutting wood and painting on the balcony still amazes me though. :)
I built a whole layout in the larger of the 2 bedrooms of a 2 bedroom apartment. It's all on my web site.
The bench top is a solid core door, $40 at Lowes. Yeah it's not a solid chunk of wood, those doors go for $100+. However, it's solid enough - it feels like a solid door when you knock on it, and it's certainly heavy enough. But some hollow core doors go for that much, this was a bargain. I coated all sides with 3 coats of poly, with some light sanding after the first and second coats. I may run some shelves underneath around the back and sides for additional storage - it's generally back far enough that I won't smash it with my legs. The top is already offset on the base - the rear legs are flush witht he back of the top, the front sticks out about 6" past the base. That power strip is a Tripplite with remote switch - the power switch is mounted to the left front leg, I can reach under and turn everything on and off. Also under the front left is where I have the jacks for a wrist strap.
45 supports or ply triangles Like the ones on your footing supports on your structure would not only be a good idea but a necessity, easier to do now than later when things start going South just trying to help I do like your concept, very cool
I am curious, what motivated you to want to build so called "free standing" benchwork on 2 legs when you could also build free standing benchwork on 4 legs and it would be more stable and able to hold plenty of weight? I'm not "getting it".
Rio Grande. The Action Road - Focus 1977-1983
I think he wants a penninsula, so benchwork on both sides, possibly 2 levels, with a center backdrop, so there are no walls to attach it to and I guess he doesn't want to go up to and attach to the ceiling.
Mine will be similar, I want as much of my layout as possible hung fromt he walls with no legs onthe aisle side. Even set back, they still can get kicked, plus they interfere with storing stuff under the layout. Some places they will be unavoidable, like where the yard stretches well over 2' wide. But the fewer, the better.
rrinker I think he wants a penninsula, so benchwork on both sides, possibly 2 levels, with a center backdrop, so there are no walls to attach it to and I guess he doesn't want to go up to and attach to the ceiling.
Sure fine. But you can do the same thing with four legs or if it's longer 6 or 8. In otherwords, it doesn't have to have a single linear row of beams. It could have twin beams all along and again, be more stable.
My current layout is around the walls and the benchwork is still stand alone and not hung on the walls, which are all sheet rock. The only thing I did was take a long #8 drywall screw and run it into studs in several places so the benchwork is rock steady and not prone to moving if bumped.
Mine will be similar, I want as much of my layout as possible hung fromt he walls with no legs onthe aisle side. Even set back, they still can get kicked, plus they interfere with storing stuff under the layout. Some places they will be unavoidable, like where the yard stretches well over 2' wide. But the fewer, the better. --Randy
I've never had issues kicking the legs on my standard benchwork. An easy way to keep that from being a problem is simply to have the out side legs in-set from the edge. There is tons of space between the legs for setting up storage shelves. No problems.
My SO didn't want me to attach anything to the walls (she changed her mind recently) so all the benchwork had to be free standing and the peninsula would've been two sided.
I tried to avoid outside legs because I wanted to have a multi-deck setup with staging tracks below the main level, have room for storage (she emphasized that), be easier to clean underneath without legs being in the way, and not bump into the legs at the same time.
Another consideration was that if I went with N scale, legs on the outside would've been a perefect target for kicking - toppling all the rolling stock like dominos in that section of the layout.
Even in H0, I'm having doubts that any light benchwork that's not tied to the walls would prevent cars from toppling, when hip-checked or its legs kicked.
Although my latest idea of going with a G shape got shot down from the sky by couple of members at my local club this week:
They said that there would be no scenic interest due to the fact that most of the track would be straight. And that due to the fact that the benchwork is pretty narrow, not allowing for much curving of the track along the way.
Their suggestion was to go with a C shape instead, which would allow for more generous curves, track overlaps and what not, something like this:
To be honest, after so many months (years?) of contemplating this layout and trying to find the best possible solution, I'm thinking to just drop the hobby altogether.I'm tired of obstacles - they are not even challenges anymore, just plain nuisances. All this was supposed to be fun, but it ain't anymore.
My space is inadequate for what I'd like to build, and so settling down for what I can build is really like giving up a dream...
T L,
By trying to build an unconventional layout and make it work you were swimming against the current so to speak and you literally exhausted yourself mentally. Trying something so different on your first layout wasn’t the best decision.
In addition of giving up the advantages of the legs, depending on what you did on top the center support could give you major problems when working under the layout, which is never pleasant.
Sorry to see you leave the hobby, but better now than after making a significant financial investment.
By the way my walk around layout is made of three sections with two 2 X 4 legs every four feet and I don’t ever remember kicking one and if I did it would be my foot that suffered not my trains.
Good luck in your future efforts,
Bob
Don't Ever Give Up
Oh, I have not left yet...it was more venting frustration than anything else.
In your benchwork, is all of it also 2x4s, or just the legs?
Why do you think that center support would be problematic when working under the layout? I would think that legs would be in the way, especially every 4 ft.
I feel I will have to revise my design, based on all the feedback here.
Or maybe just frame the walls around the open spaces in the basement and create a closed room from it. Then just mount everything on the walls, as thats tried and proven method.
Did you check on my previous layout on my web page? I had legs every 8 feet - plenty to hold it up. Each section of that is fairly lightweight, 1x4's the long way, 1z3's cross bracing ever 2', and 2 layers of 2" extruded foam. With the legs unbolted even the 2x8 sections were easy to carry. Most section only had a pair of legs at one end - then the next section would bolt on to the leg end of the previous section, and had legs on its free side. On the drawing, it was the part on the right, which was the back wall of the apartment, that had legs on all 4 corners. Thus where each half ended by the door for a liftout, there were legs. Only the small section which was 18" wide by about 3 feet long between the door and liftouts for the door and the work area had to be attached to the wall to keep it from wobbling. The rest was quite stable and I had no problem with any magnitude 10 earthquakes knocking anything off the rails.
As for the G shape - there are plenty of places there, especially on the part that goes along the pillars, for the main line to meander with very wide radius curves between the front edge and the back edge. There is no requirement of that design to lay any of the track perfectly parallel with the fascia. You have your yard drawn as perfectly straight lines, which it doesn't have to be either. The G shape gets the longest mainline run in the available space, which is important if you want to have a nolix to a second deck.
And I know where you are coming from. When I started house hunting I was looking for a modest ranch with a full basement. I don't need a giant house, there's 2 of us, 2 small dogs, and 2 (now 1) cats. And I don;t care what the bank tells me I can afford, I didn;t want to spend that much. Two reasons for a ranch - I have very bad knees and climbing stairs is not very much fun, and a ranch with a full basement as the same square footage of basement spoace as living space - so a say 1300 sq foot house has about 1300 sq ft of basement. I was doodling arrangements to fit in such a house, which gave me 2 runs along the walls plus a double sided pennisula, all with 32" minimum radius and 4' aisles.
Great, you say... well, things don't always work out that way. The house I found is actually a raised ranch - so I lose something like 20 feet of length to the garage. More like 25 - as the house is actually closer to 1800 sq ft than 1300. I've considered pulling a Tony Koester and having an offset wall built in the garage that clears the hood of my car to add an additional bunch of space, but that's been shot down - plus it would mean something would have to sit outside. Despite it being labeled a 2 car garage, I have no trouble getting 2 cars PLUS my truck in it at the same time. And the laundry, and all plumbing for it, is right on the wall that would have to get knocked out to access this additional space. So, not happening. The space I have left is far from ideal - the electrical is all out in the garage, but the furnace and water heater for some reason are in the right front corner - despite both upstairs bathrooms, the downstairs bathroom, and the laundry all being right by the garage. Only the kitchen sink is on the right side of the house.
I tried all sorts of configurations before finally deciding that I have to go double deck if I want the length of mainline run I am looking for in this space. It's bad enough that I will have a 2 level removable section for access to the furnace and water heater, but otherwise there will be no duckunders or liftout sections. So yeah, the layout is going to be much different than the ideal I dreamed aout. The space has made me go more freelance, as there really isn't room to fit the one feature I wanted, the large passenger station built in the middle of a wye connecting 3 different branches of the railroad. That was going to be my ultimate goal - scratchbuilding a model of that station (never has been and I seriously doubt ever will be a kit of it). I do have an idea of how I might be able to fit it in, but it would end up being well away from the main yard which in reality was right next to it. Although typing this gave me another idea... I don't think it will fit but now I am going to look at my plan and see.
Of course, there are tradeoffs - I DO have a very nice pool to relax in all summer. And it's an all gas home, best for cooking and cheaper for heating - speaking of which it is a very efficient 3 zone hot water system. So utility costs are low. And it's 5 minutes from my office.
As it always happens, life drags me away for a week again, just because...
@rrinker,
I did look through your old layout construction and basically that's one option I thought to do, too. Open-frame benchwork, legs, plywood and foam on top.
The two 2" sheets of foam would give for a nice amount of playroom to carve things into, but I am not too sure about double decking with that much foam. Counting the foam, plywood and the benchwork that's a lot of vertical realestate taken.
Considering the G shape, I am having a hard time figuring out how would I do a no-lix in that configuration, especially with some of those narrow sections.
I wanted to combine a front to back no-lix, where a decline would start on the front of the benchwork, dip under it after adequate clearance is achieved, then go along the back until the lower level is reached.
Having said that, with a G shape, constructing the above might be somewhat difficult and I really want a simple benchwork. I'm just not sure where would this extra no-lix trackage fit and connect to the rest of the layout?
Your current house sounds like a nice place overal. When you say a "raised ranch" I assume it's what they call back-split up here?Yes, you traded some perks you wanted for your railroad, but you gained other amenities that make the place just that much more enjoyable.Besides, you don't have to contend with a 6'5"~6'7" ceiling in the basement (and being 6'3" tall). :)
Back to my benchwork test, I believe I will have to anchor the verticals to the ceiling and that would give them needed stability uptop.
I will also add strategically placed 2x2 legs on the outsides and forget the whole gassets thing because I don't want to deal with trying to match my open-frame crosses with my main verticals. Plus this will give the top surface needed stability front to back.
You don;t need 2 layers of foam, for sure. I just did that because I built the first section when I was living in a smaller place and was goign to build a small switching layout, and oen scene I wanted to replicate needed some decent amount carved out - with a single layer of foam it would have been down to the plywood underneath. I ended up moving and rather than scrapping a 2x8 section of benchwork I just built the rest the same way. Mainly I was showing the underlying freestanding benchwork, what you actually attach on top can be anything.
With the G shape, you will get a good chunk of the rise on the midpoint curve. At the first narrow section, the higher line up on a retaining wall would work, on the second narrow section the difference should be enough to have the two lines seperated with scenery.
Let me add one more thought to your original bench work scheme that could make it work. If I could figure out how to sketch it here, it would be pretty clear.
a. For the uprights, go to 2x6 instead of 2x4. Why will become clear in step d.
b. Widen the base so both bottom bases come out to within 6 inches or less than the layout width on that side. This will give the balance needed. Could even use very heavy duty castors to move the layout.
c. Join the uprights with L girders at the heights you want to build the layout from. With 2x6 and L girders, this gives you about 8 inches of bearing width for the next step.
d. Instead of modules, span the width of both modules with single joists running across the tops of both L girders at each upright. If you only have two uprights, put one on each side of both. Attach the joists to the L girders from below per normal AND with 2-3 screws to the 2x6 uprights.
From this point you can built out either in L girder, open grid, module, etc. This form of construction and attachment will provide a stable base. I used this basic design to build a canoe and kayak rack for the garage. It easily supported a canoe and two kayaks.