Module length

Yes, I made the module to fit nicely between the architrave and the door but there were two problems with that idea. Firstly, at the time of construction, I did not have a layout height set. As the above photo shows, the door latch hit the side of the module and wouldn't open fully.
The other thing was the battens we used to mount the brackets on the wall were thicker than the architrave by several mm and the door rubbed on the end of the module.

To fix these two issues I shortened the end of the module by around 30mmm. Luckily there was enough space to sandwich an end piece between the two sheets of MDF that formed the base under the foam. I also had to carefully cut the track back.

In the pic above you can see the section I chopped off sitting on the upside down module with a new end piece in place. You can also see the rail roadbed extending past the end, ready for the end plate to be attached.
I think I was very lucky that major surgery of the module wasn't necessary! The door now swings open nicely with plenty of clearance.

Mounting brackets

Problem 2: Some of the mounting brackets weren't square to the bottom of the module.

Most of these brackets only needed tightening/loosening of the mounting screws to make them sit square. On one bracket I had to pack out the bottom (a piece of 3mm MDF did the job) to level the top. All nice and square now

Corner coving

Problem 3: The coved corner.

The only other problem area was the coved corner. I cut the corner a bit short so there is quite a gap between the rail/ground level and the cove. Although quite visible at present, I haven't done anything with this. The area will be heavily forested so that the gap should 'disappear' (fingers crossed).

I used Kapton heat resistant electrical insulation tape to span the gap between backdrop and cove piece as it is very thin. If I ever need to pull the layout room down I can just slice the tape to separate the backdrops from the corner. Nice and easy.
Over the course of the year there has obviously been some movement of the building and an area of the tape has lifted as the backdrop and cove have moved separately. This may have also been how I laid the tape on, stretching on side rather than evenly. Again, this area will be hidden when the module is forested and the backdrop trees painted in. But in future I will make sure I lay the tape as evenly as possible.

So we had a couple of problems when installing the layout room, but they were not too bad to sort out. Easy remedies for the most, but also a couple of things to consider when planning and building the next sections.

I'm sorry but...

That first photo made me laugh out loud. So close yet so far.

I feel your pain, been there.

Fun and games

Ah yes, it is one of those funny moments, more so in retrospect than at the time

The things you learn by doing!

I've had that problem

I've had that problem before - with the door latch. But not with a layout, it took me a while to remember but it was in a house where I had a big desk in a small bedroom. I'd even measured the room before I bought the house to make sure my desk would fit and the measurements said there was an inch to spare - but with the molding along the floor and various things leaning in different ways it came out at a 1/4", and I'd only measured to the door edge, not counting the latch, which hit the edge of the shelves along the back of the desk. 

I solved it by taking the door knob apart and removing the latch spring and then taping over the latch to hold it retracted. I wasn't ever going to be wanting to latch the door shut anyway. 

Square houses

I find it interesting that houses aren't as square as they look. I think that was the problem with the mounting brackets not being level. They were level with each other at the wall, but the wall wasn't square, so upper and lower mounting screws were not in a vertical line.

Yep, walls being absolutely plumb is definitely a

goal, but not mandatory.  I've seen walls in mid 20th century homes that were 1 1/2" out of plumb floor-to-ceiling, and that was on the main floor; basements didn't get that kind of close attention.

Not to mention, many basement completions were done by the homeowner long after anyone who owned a level had left the scene of the crime.  

Blair

Walls aren’t flat either

Walls aren’t even generally flat - there are bumps, twists, and dips if you look really closely.  Some of it is from pulling the sheetrock against studs that aren’t necessarily perfectly plumb, straight or lined up.  For walls that get finished with a plaster skim coat, that can add more variation.  The plaster skim coat needs to look smooth and flat, which is not at all the same thing as actually being flat.

90 degree angles

If you want to have some fun??? go around with a framing square and see how many angles aren't 90 degrees.

Paul

21st century lumber

Square rooms need straight timbers, and lordy, you're not finding that in your average tract home.  It was instructive to watch a bundle of "whitewood precut studs" get released from the steel bands at the local big box.  A couple sticks assumed odd angles immediately, which was not a concern.  What was worrisome, was walking into that aisle not an hour later, and seeing what could have passed as a hydra nest.  The pack had grown maybe 15%, and for every stud I pulled for the mower shed, I discarded two. The quality was horrible.

It's been a few years and a few thousand miles, I can't recall where I saw the "timber fields" in the Pacific Northwest, but I'd like a few hundred board feet from one of those trees.  Straight as a flagpole, they were...

Tape measures are your pals!

The old adage "Measure twice, cut once" somehow skips model railroaders.

I measured my room countless times, down to the fraction of an inch. I built my layout in sections which were bolted together and then the track went over top. But as many times as I measured the room, I was short by at least 3 inches. Better short than long, but I still don't know how I goofed it up.

I cut a 2X4 and screwed it to the end of the outside edge of the module along one wall, then put scenery over top and you'd never know unless you looked underneath.

Laser tape measure

A laser tape measure makes it much easier to measure 10 times, cut once (2 doesn’t seem to be enough for me to be sure to get it right).  With a regular tape measure it’s hard to impossible to accurately measure all aspects of a room without a helper to hold the other end in places there’s nothing to hook it on.  With a laser tape measure, you don’t have that problem, so quick double/triple/.../octuple checks are easy.

Two years ago

Here's a pic of the module on the floor after a year before I started on the room itself. You can see there is plenty of clearance with the door at floor level, but up at layout height all of that space vanished. Thicker battens on the wall and also the backdrop thickness (3mm MDF) accounted for some of that space being used up, but not all.

Measured nicely, but in the wrong spot, and not taking into account the materials used during construction (which I only had a vague idea of at the time).

re: 21st century lumber

 Nothing new, really. Must be almost 40 years ago now, I helped my neighbor convert part of his garage into an office. He put a chair rail around the room - on no wall, except the one he built himself dividing the garage into 2 sections, did the molding lay flat on the wall. And this is in a house built in the early 50's.

                               --Randy