Modern Flatiron Scratchbuild - Part 1

A current project I am working on is a building to fill a problematic gap right in the front of my downtown.   The shape of the block requires sort of an asymmetrical "flatiron" type style which is not really something you can get commercially.

I've been thinking up and collecting ideas on how to scratch build modern buildings (my last scratch-build was almost 2 years ago) so I've been a bit anxious to try out some of these techniques!

Basic Structure:

Clear Acrylic Sheets and Sintra:
I started off by getting my dimensions for this unusual location, and eyeballing what the best height would be.  I then set about the tediously slow process of scoring clear acrylic sheets with a hobby knife to cut these sheets to the right dimensions (the clear acrylic can be found in most home improvement type stores).

The key I've found with getting good, straight edges with acrylic is that you don't actually want to 'cut' all the way through...that seems to either lead to a devastating crack or an uneven break.  The trick is to score it just enough so that you can snap the piece along your score line against a solid table edge or something.  Its not easy, and is the most aggravating part of the project!

Windows and Exterior:

I'm using my new Kato buildings (shown in the top photo) as a guide for floor height, which is about 22.5mm or 7/8".  I decided to use Evergreen Plastics 349:  .040x.250 (1mm x 6.3mm)  as the exterior material to go between the floors.  At 6.3mm width, they are just wide enough to cover the 5mm foam core sections which will be the interior floors.

I'm not sure if this is making any sense, so maybe the pictures below will make it more clear what I'm talking about!

Given that I have my 7/8" floor height, I went into Intaglio (basic drawing program) and created a grid for the exterior window frames.  The vertical distances are 10mm, which gives a pretty good indication of windows.  I printed this drawing onto transparency paper using a laser printer and - wallah! - I have my window frames!  This is a much easier way of adding window details than trying to cut precise little pieces of styrene, etc...  Its a technique I read about a couple of years ago in Railway Modeller.
The Evergreen styrene strips will go on top of the transparent materials (which will go on top of the acrylic sheets.  Everything is going to be glued together in the space which will be covered by the styrene strips.

For the styrene strips themselves, rather than making the angle two pieces, I decided to try and keep the pieces together and try to avoid a problematic seam on the corner.  I scored the back of the styrene, painted, and then used a bit of heat to make the bends.
Ground Floor and Base:

For the ground floor/lobby, I decided I wanted it recessed from the rest of the structure (which seems like a typical design), but nearly double height.  Again, I used the 'ground floor' height of the adjacent Kato building so that they would consistent with each other.   The base itself is a sheet of styrene (Sintra is too thick for a floor), which I then applied some styrene "L" pieces to hold the plastic windows (which will be the support for the entire building) solidly in place.
I decided this building would consist of a high level of 'black and white' contrast.  Most of my buildings are grey, so a bit of a contrast was in order.  I decided to color the ground floor in what I hope looks like a black granite or marble material.   The entry way carpets are just electrical tape.

Finally, I also started working on the interior floors.   These are mostly cut from foam core, with additional vertical sections to which I glued a homemade interior wall patterns.   A picture does a better job of explaining this:
Next up is applying the transparent window sheets to the acrylic shell, then applying the exterior styrene pieces on top of that!


  1. This looks like a good start. Is the reason you're using Sintra instead of something like 2mm styrene ease of use, or something else? It seems a bit thicker than necessary in this applcation.

    I want to eventually scratchbuild some urban buildings. Your articles about scratchbuilding have given me a lot of ideas.

  2. @Ken - Thanks Ken! Yes, the Sintra is a bit thick, but its a lot easier to cut and a lot cheaper! I'm only using it in a couple of areas where the thickness won't matter.

    Although, ironically, I'm using foam core for the floors which are even thicker than the sintra!

  3. Hi, great work. This gives me some ideas to. Is foam core the same thing as loose cell foam or like extruded polystyrene? In Australia the names of some things are slightly different?

  4. @ Dallas - Thank you! "Foam core" is typically used as a backing for picture frames (I believe), although it has a lot of 'craft' type uses and can be found in many craft or art supply stores in the US. Its sort of sytrofoam (without the 'balls') coated with paper. It may also be called 'matte board' I believe.

  5. Cheers! I think when I have my track laid and wired I might give this a go. Though my last attempt at soldering was a complete failure!