Monday, December 8, 2014

Build Exterior Walls With Foam Board Inside & Out

Model making showing walls, doors and floors.


Models of houses or buildings often use foam core to represent the thickness of the wall. Foam core is a sturdy, flat board that is easy to cut and manipulate. It provides a clean, finished model that can be embellished with representations of windows, doors or other features. Creating the walls out of foam core does take some practice and sharp tools. Once you have made a few cuts, you will be able to craft even intricate walls and make them look good.


Instructions


1. Draw the floor plan of your building on paper. Transfer the measurements or glue the floor plan to a sheet of foam core. Use a spray adhesive and rub the floor plan from the center out to remove any wrinkles.


2. Set up a guide to help you miter cut wall corners. On models in which the paper surface of the foam core board is preferred as both the interior and exterior wall surface, each corner must be mitered.


3. Tape a metal ruler to the edge of the work table so it overhangs the edge of the table by 1/8 inch. You will use this ruler as the bottom edge of a miter corner cutting guide.


4. Line up a piece of scrap foam core that has a straight edge with the edge of the ruler and tape the scrap down securely. Use scrap to practice making the mitered cut until you are comfortable with your results.


5. Measure the thickness of the foam core. Transfer your measurement to the flat surface of the scrap foam core. Measure away from the straight edge of the foam core and draw a line parallel with the ruler. For example, if your foam core is 1/4-inch thick, measure from the edge of the foam core 1/4 inch and draw a line. Place the second metal ruler on the line and tape it down securely (tape it away from the ruler edge where you want to cut).


6. Cut through the top paper of the scrap foam core by drawing your cutting knife along the top metal edge. Do not try to cut deep. After the first shallow cut, place your sharp blade so it touches both the top and bottom ruler edge at the same time.


7. Cut the scrap at this angle. You should create a 45-degree bevel cut. Use this cut for the corners of your walls so both the inside and outside of your walls are paper covered.


8. Measure the length and height of your first wall. Usually the walls of each floor are of one height so you can cut several strips of the same height. Cut your wall to length and then use the miter guide and your knife to bevel both ends. Apply white glue along the bottom edge of the wall and glue it over the floor plan so the sharp point of each end are on the outside of the wall corner.


9. Continue cutting walls. You will soon note that your miter or 45-degree cut follows the inside/outside corner of the wall not the inside/outside of the building. Many buildings have recesses. This means that some walls will have opposing miters and others will have miters going in the same direction. When you join two walls, glue the miter. To keep the wall level and straight while it's drying, insert straight pins high and low through the miter into the adjacent wall.