Craft Section

CAV Terrain

Part I: Plastic Sci-Fi Buildings

by Dewen

Building urban or industrial structures from scratch for a CAV gaming table is simple and inexpensive. I use various materials that I collect around my home or purchase. Here are some basic steps for building your own structures.


  • Plastic electrical boxes. The blue and gray boxes found in hardware stores
  • Hobby knife, metal rule, cutting mat
  • Hacksaw, hobby saw, or bone saw, if boxes have mounting brackets
  • Spray primer, black or gray
  • Spray paint
  • CA glue
  • Plastic cement (Plastruct Plastic Weld Cement)
  • Model glue (all purpose, clear drying)
  • Styrene sheets and strips. The scratch building materials that can be found in hobby stores, especially ones that sell model trains
    • Plastruct square tile sheet styrene with 5/64” grid
    • Evergreen metal siding sheet styrene with 1mm spacing (thickness depends on preference)
    • Evergreen strip styrene .030 x .250”
  • Base material (pressed board, mdf, …)
  • Various details
    • Toy blocks (legos)
    • N Scale details
    • Miscellaneous plastic pieces (miniature bases, sprues, kids’ toys…)

Electrical Boxes

I purchased plastic electrical boxes from my local hardware store. Most of the boxes I used cost $0.79 - $1.15. Larger ones made from thicker plastic may cost $5 or more.
Some have mounting brackets. I used a hacksaw to cut them off and then cleaned up the burs with my hobby knife. I recommend something finer than a hacksaw, such as a hobby saw or dremel. The saw was hard to handle because of its size and marred and scratched the side of the electrical boxes.
Other electrical boxes do not have the mounting brackets. The gray box on the right was really cheap. The blue box pictured is a thicker plastic and cost a few bucks. I removed the screws from this type.


Some of my details are blocks (legos), plastic sprues from minis, plastic mini bases, scrap kids’ toys, and N Scale details. I purchased a kit from my local hobby store called Cornerstone Modulars Roof Details by Walthers in N scale ( ). It costs about $10 and adds nice details to your structures and really brings them into scale. I also found some N scale drums that looked great next to my CAV garage. The doors and windows are styrene plastic building materials from my local hobby store. Evergreen and Plastruct are popular brands.

General Instructions

Building Overview

  1. Remove brackets and other unwanted screws and parts from the electrical boxes.
  2. Wash the boxes with warm water and a drop of dish detergent to remove dirt and adhesive residue from stickers.
  3. Collect and assemble details. The building details may be applied before and/or after painting.
    1. For plastic pieces added to the buildings to change the shape, glue them on before priming. When gluing a plastic piece to the building before priming, I use Plastruct Plastic Weld Cement. The pieces you are gluing must be compatible with the cement. Most electrical boxes are. Test the plastics you are using by applying a small amount. This type of adhesive fuses the plastics together.
    2. If you want the doors and windows a different color, prime and paint them separately from the building. When gluing the pieces together that are primed and painted, I use CA glue. I like the brush-on glue that starts purple and dries clear. Brushing clear glue on to white plastic is hard to see.

      The pieces circled in blue were added to the building after painting. Those details are kids blocks. The details circled in red are cemented to the building before priming. The square piece is a toy block. The hex is a miniature base of some type. The hood is from the Modular Roof Details set.
  4. Prime the boxes.
  5. Base coat with spray paint. I used Testors and Tamiya because of the color selection, fast drying time, and flat finish. If you own an airbrush, your buildings will look even better.
  6. Cut base. I used 1/4" board cut to a size to accommodate the building. I cut mine in various sizes. When laid out on gray felt it creates a look of blocks with streets.
  7. Prime base.
  8. Paint base. I simply sprayed a shot of gray around the sides on the black board to create value.

  9. Glue the building to the base with model glue or another all purpose gel type glue that dries clear. CA glue will not work.
  10. Clamp the building to the base or set a weight such as a heavy book on top while the glue dries.
  11. Seal your project with a matte spray.

Doors and Windows

The personnel doors are just styrene strips cut to approximately height. I used Evergreen strip styrene .030 x .250” cut to the desired height. You can buy nice N scale doors. I made rollup doors from styrene sheets with ridges. The small rollup doors were cut from the sheet, primed, painted, and glued. Evergreen makes sheet styrene called metal siding with 1mm spacing. To cut several pieces I used The Chopper by North West Short Line. It is a hobby tool for cutting balsa and styrene strips. You can also use a hobby knife and metal ruler to cut the pieces over a cutting mat. A cheap substitute for a cutting mat is a corrugated box. The large rollup door is a styrene sheet with styrene strips cemented to the sides. I cut the door from the sheet to desired size. I cement the styrene strips on the top with cement and let it dry. I then trim the angle with a razor blade or sharp hobby knife. I then glue the sides pieces to the door.
The windows are styrene sheets with a grid pattern. I used Plastruct square tile sheet styrene with 5/64” grid. I cut them to size. Prime, paint, and glue to the building with CA brush on.

CAV Terrain Miscellaneous Details

Details help set the scale for the structures. I used a variety for my buildings.
The circular vents on the round building are Modulars Roof Details. The railing on the balcony is N Scale railing that is sold in packages with strip and sheet styrene at hobby shops. It was tricky gluing these on. I used some round strip to reinforce it.
Other details are blocks and various plastic pieces from kids’ toys. These were primed and painted before gluing to the finished building. The grates or vents from blocks (legos) and other similar pieces can be applied without priming or painting.

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