Model Construction


| June/July 1988



Engine

1. Paul Breisch 187 W. Ridge Pike Royersford, PA 19468

Mr. Whitey Boswell of Greensboro

2114 Alamance Church Road Greensboro, NC 27406

Many of you will remember the back cover of the August 1987 GEM showing models of the Fuller Johnson engines. Since the magazine came out, there have been inquiries from persons throughout the States wanting information on the casting kits for building those kinds of models. After answering numerous letters and telephone calls about the source of the casting kits, maybe it would be good to mention the names and addresses of casting kit suppliers from which I have ordered materials. Please refer to a listing at the end of this article. Please refer also to April 1987 GEM, page 28, listing model kits and suppliers of that date.

The photos shown on the back cover of August 1987 GEM were made in January 1987. Since that time a headless Witte (De bolt Castings) and two more Fuller Johnsons (Ed Chick's Castings) have been completed. Quite a number of questions have been asked about various machining and construction details, so a few photos were made of these last two Fuller Johnsons to illustrate my ideas for machining and building.

The crankshaft is fashioned from a rectangular cold rolled steel (CRS) bar. (photo No. 1) The selected bar is covered with layout ink (By Kem Blue) and the two centers scribed on the ends of the bar and the entire profile of the crankshaft is scribed on one side. The scribing gives visual guidelines for removing all unwanted metal. As much metal as possible is removed with a band saw and the remainder is turned on a lathe with the 'throw' portion being completed first. As the picture shows, one end of the crankshaft is 'finish' turned then reversed end for end between centers and supported by a steady rest before the other end is completed. An 'oilite' bronze bushing is held by the steady rest to allow accurate alignment of the shaft. As the second end is turned the bending of the shaft due to tool pressure is greatly reduced resulting in a more accurate turned crankshaft.

The next several pictures show the model in various stages as assembly progressed. As the pictures show, all painting and stiping is done before assembly begins. After machining, each casting is smoothed by grinding, hand filing, and sanding as necessary to remove uneven surfaces and parting lines left by the foundry process. All holes or voids and any abrupt changes in surface contour are filled with automobile body filler and sanded smooth. All oils which were used for drilling and tapping are removed by washing the castings with denatured alcohol. Machined mating parts and casting surfaces, drilled and tapped holes, and all functional bores are masked using masking tape. To prepare the metal surface to receive the final paint, all surfaces are primed with gray primer paint (Rust-Oleum or De Rusto), two coats minimum. About twenty-four hours of drying time is allowed between coats. This material is readily available at most hardware stores. Next follows three coats of a chosen enamel paint. Again Rust-Oleum or De Rusto is a good choice. A small one-inch paint brush works very good. Spraying is not necessary to produce a great-looking paint job.

After the paint has dried for about a week, decorating by hand painting, pen striping and various designs can be painted onto the enamel surfaces. This is the ideal time to apply designs since the parts are accessible on all surfaces. Painting is much more permanent than adhesive-backed pen stripes. You need not be an artist since 'air brushes' and 'striping rollers' (see reference 6 for catalogue) are available. For those persons who are artists the regular striping brush does a beautiful job. If an error is made in the decorating immediately remove it with a cloth soaked in gasoline and start over. The gasoline will evaporate leaving a clean surface to try again. All the decorating on the engines shown was done with a 'striping roller' and spray stencils and an 'air brush'. Now for the ideal way to decorate an engine is to have an artistic wife to paint for you as Betty Duggins of Winston Salem, North Carolina does for her husband Henry. They have truly beautiful equipment when engine showing time comes. By the way, Henry and his son Mike build most of their exquisite models without the benefit of castings.