Scratchbuilding

I have been doing a little scratchbuilding here and there over the years, but earlier this year I landed a project that was a first for me....a complete scratchbuild from the ground up. A client wanted an architectural model to present to the prospective neighbors. Now that the model is complete and delivered, I can write about the extensive amount of work it took to complete this four month project.

The building is a combination residence and auto shop, with a very large footprint. The client wanted the model built in railroad HO scale, or 1:87. The architect provided a full set of plans in PDF format, which I had printed to scale using the large format printer at my day job.

Once I had the plans printed, I started researching the materials I would need to buy to replicate the materials of the actual building. The outer walls are corrugated steel with stone wainscoting, and the roof is a 12" standing seam steel roof. After a little online research, I found some products from Evergreen and Plastruct that fit my needs perfectly.

The first thing I quickly realized, even at HO scale this is a large model. The footprint of the main building is about 18" by 28". With the landscaping base, the overall size ended up close to 30" X 40".

Once I had the materials on hand and my plans ready, I started construction. I decided to include the interior walls of the building both to increase the strength of the model and provide an option for interior detail if the client requested it.

I built the inner and outer walls with layered sheets of .040 styrene to get them to scale thickness.
Using a small metric ruler, I transferred the positions of all windows and doors to the correct locations on each wall.



I also started constructing the doors, windows and other detail elements using strip and sheet styrene. I only needed to build one of each, since I would be casting the copies out of resin later. I will also do the same for the decorative pillars supporting the overhangs on each end of the building.

Once I had the first few parts assembled, I poured molds for them. I ended up making 5 different molds for this project. Three different types of doors, two windows, a column and the glass block window. Most of these were combined into larger molds to save material.

This is the glass block mold, made with Composimold.

This mold was used for the rear main doors, tower doors and all standard outside doors.

This mold was used for the tower windows and garage doors.

Resin copies of tower windows, doors and columns.The master column is on the right.

I also had to get some clear resin to create a glass block window for the main bathroom. I built the master using styrene strip and bar stock and cast it with a two part clear resin. This piece was a little tricky and the resin took a long time to cure. I ended up leaving in the mold for nearly 72 hours, and it was still a little flexible when it came out.

While working on all the detail pieces, I also started assembly of the outer walls. Once I had all the basic forms built and cut out, I started gluing the textured styrene sheet to each wall. The corrugated metal walls were replicated using Evergreen 4527 Metal Siding. The stone wainscoting was then glued on the lower portion of each wall. Plastruct 91561 Random Stacked Stone sheeting was a nearly perfect match for what the client was looking for. The capstone trim was a combination of styrene angle and bar stock built up to the visually correct thickness.

Main bathroom window with detail, before adding glass block. Small square windows are cast in resin.

I printed a scale floorplan that I glued to the scenery base. This would be my primary guide for placing the walls and landscape elements that I wanted to include in the model. I frequently dry fit the walls together to check placement and make sure everything was lining up correctly. I decided to set the building at a slight angle to the base. This made it a little more visually interesting and also gave me a little extra room for the driveways I had to put in later.

You can see from the floor plan how large this building really is. The long shape on the left represents a 52' transport tractor trailer. The line of vehicles on the right is the garage. The residence is at the top of the photo. All other space is for fabrication/shop area. 

Once I had the basic wall construction done, I started on the "tower". I began construction by cutting a floor template and a roof template and connecting them with wall sections cut from .040 styrene. The wall sections were constructed the same way here, layering .040 styrene and finishing them with textured styrene. The upper windows were then added to the top of the tower before starting the framing for the roof sections.  

 

 

 
 This part of the construction was a little tricky - I ended up building several different frames for the 
roof until I found one that worked well. The resin windows made things difficult as I had to switch to superglue to get them in place, and they broke loose a couple of times. I did have to do a little surgery on the window sections to get a good fit, but once I had them trimmed and sanded they worked pretty well. 

The roof sections are built from panels cut from Evergreen 4521 Standing Seam roof, edged with .060 angle and .030 strip styrene. I also added the doors and windows to the tower at the same time. The adjoining section on the tower connects it to the main building.

After a lot of filling and sanding, the tower section was nearly ready for paint. I would not connect it to the main building until the model is secured to the base.