Craftsman Tool Chest: 6
Building with Mat Board
By George Riley/photos by the author
Mat board is an excellent product for replicating poured concrete, stucco or even adobe masonry buildings. While not as popular card stock material once was for constructing model structures, it is an easy to use, readily available and inexpensive product that lends itself to model building. Large 32-inch by 40-inch sheets of mat board in a variety of colors are available at most large craft retailers or framing shops for less than $20.00 a piece. A sheet will yield material for a number of projects. Often additional savings can be had by purchasing off cuts and scraps from a framing shop.
All that is required to work with this material is a very sharp hobby or mat knife and a metal straight edge, preferably one with a non-slip backing. Select sharply pointed No. 11 style blades for the hobby knife from either Micro-Mark, Excel or Testors since these are usually sharper than most other brands. Heavier duty mat knives with replaceable blades are available from most large craft outlets that sell mat board. These are excellent for cutting out larger pieces from the sheet however; a sharp hobby knife is still a must for cutting window and door openings in addition to making smaller parts.
The best way to become familiar with working with mat board is start with a kit. Alpine Division Scale Models offers a number of quality model kits in a wide range of price points and subjects. For this step by step demonstration Alpine’s #8407 Orange Vista Packing House is featured. The kit consists of die-cut mat board, pre-cut strip wood, a vacuformed plastic radial roof along with an assortment of plastic and metal details. While the Packing House has a fairly large foot print, a novice will find the kit easy to build into an impressive HO scale model.
A wide range of readily available adhesives can be used to assemble mat board models. Aliphatic resin carpenter’s glues, white casein glues, PVA or acetate adhesives work equally well. Thick body ACCs can be used to permanently attach small detail parts. Ambroid glue is used for the general assembly of the model with Aleene’s Tacky Glue used to attach some of the glazing and large details.
Step 1: Begin by laying out the mat board and strip wood parts. By identifying each piece before beginning construction of the model mistakes made by assembling the parts incorrectly will be minimized. Once familiar with each of the items begin sealing each one. Deft spray lacquer sanding sealer was used on our model. This product is available at most home improvement stores. Shellac, flat varnishes, model airplane dope or clear polyurethane can be used as a sealer as well. When dry polish each piece with 0000 steel wool to remove any remaining fuzz or blemishes. Some of the more porous wooden items like the balsa loading dock required three coats of sanding sealer to get the smooth surface needed. While this step does take time, sealing all the porous parts (wood and cardstock) will result in a durable, long lived model.
Step 2: Remove die-cut walls from the carrier sheets and the waste stock from the die-cut window openings using a sharp hobby knife and straight edge. At this stage it is a good idea to add layout lines for the interior floor and roof bracing. A small machinist ruler with an adjustable clip or piece of tape will make easy work of getting the measurements consistent.
Step 3: Add the interior bracing using the provided sealed strip wood. Clamp the wood in place until the glue has completely dried, this will give a much stronger joint. It is a good idea to keep a supply of 1/8 inch, 1/4 inch and 3/16 inch square strip wood on hand to use should additional bracing need to be added. When the interior bracing is dry, the walls and floor can be assembled.
Step 4: With the walls assembled add the strip wood pilasters, window sills and lintels. Clamp these parts in place where practical and allow the glue to completely dry. A cotton swab will let you wipe off any excess glue that might ooze onto the surface. Once all of the surface details have been added and the glue dry give the model an overall coat of sealer and let dry. At this point any blemishes can be corrected and smoothed out with fine sandpaper and steel wool.
Step 5: Apply an overall coat of primer to the model. This will provide an excellent surface for subsequent color coats and allow even uniform coverage of different materials. Make sure to prime the roof panels, loading dock and other parts that have not yet been attached.
Step 6: Begin applying the color coats to the model. Commercial spray cans were used to finish this model of the packing house. Flat tan, dark gray primer, flat white and concrete gray colored paints were used. After one color was applied and allowed to fully dry, it was masked off using blue painter’s tape before the next color was applied. This step may take several days to complete and should not be rushed. While painting is in progress the small added detail parts can be cleaned up, painted and set aside to dry.
Step 7: Glue the window glazing, interior doors and ‘glass block’ in place and clamp until dry. Aleene’s Tacky glue was used to secure these parts since it dries clear and remains flexible making it particularly effective for attaching clear acetate and plastics to wood and cardstock. The loading dock, office annex and some of the detail parts are applied at this stage of assembly as well.
Step 8: The pre-painted flat cardstock sub-roof is lightly glued in place using Aleene’s Tacky Glue. This allows the roof to be pried loose and removed later should the need arise. Clamps hold the sub roof in place while the glue sets.
Step 9: The vacuformed radial roof panels have been pre-painted and weathered prior to being attached over the sub-roof with Aleene’s Tacky Glue. The panels are held in place while the glue dries.
Step 10: All that remains at this stage of construction is the addition of the small detail parts using thick body ACC glue (super glue). These include the various roof vents, conveyor and other small bits and pieces. With these added all that is left is to weather the model and place it on the layout.
Once you have mastered a few mat board kits, it is only a small step to designing and scratch building your own unique models using mat board in their construction.
Small Machinist's Rule (Item #10114), Bulk Pack No. 11 Blades (Item #14178), Miniature Spring Clamps (Item #82780), Straight Edges, and other useful model building tools are available from Micro-Mark.