| March/April 1982


#1- Associated (1978) 1 piston.

Rome, New York 13440

Making a model gasoline engine has a special reward for the builder and he has earned the reward as soon as the little engine runs on its own.

I have made eight running models, 3/4' piston to 1?' piston. Two models were made from kits. Five were made from my own wooden patterns scaled from an original engine. One was made from scrap pieces of steel (1/4 scale of Stover 2 or 3 HP). A 4 cylinder 1?' piston is now the challenge.

The 1/4' - 32 spark plug is short life (a few hours only), hard to find, and high in price. Champion and the Japanese make a 3/8' plug that holds up, is moderately priced and small enough to look good.

A 1?' piston is a good size for a beginner to start with; the smaller sizes are very sensitive to fuel mixture and usually will not run at the desired slower speeds. Good compression in a gasoline or internal combustion engine is a must, so any builder should plan on using piston rings. Two rings (cast iron) in one piston ring groove do an excellent job. Use two ring grooves 4 rings. Vertical engines with open crank-case will require more lubrication for the piston than does the horizontal.

If you plan to use your own wood patterns find out first if a local foundry will do your work-most will not help you even for extra $$.