[Headline: SAM35 Speaks tips and tricks]
SAM35 Speaks is the British version of the US SAM Speaks, the house organ of the Society of Antique Modelers (SAM). The British publication has a different format at 6 inches x 81/4 inches, more pages, and smaller print, so there’s plenty of reading material in an issue.
Membership to SAM 35 is approximately $83, and it includes the monthly publication. I’ve been perusing some past issues and find the British writing style uses more words, resulting in more humor.
An array of subjects is covered in each issue such as FF, RC, CL, rubber, gliders, scale, engines, letters, and rocket power (Jetex, CO2, and such). The variety is made possible through a large group of contributors responsible for each protocol.
There is usually a technical idea (or two) to which I hadn’t been exposed or had never considered. For instance, Jetex rocket motors lose weight as they burn. That means a rear-mounted motor design will undergo a significant CG change, so a centrally mounted motor would be a good idea.
Film Connections to Modeling
Camera film has a couple of interesting connections to early modeling. Before commercial model adhesives were widely available, modelers dissolved film in acetone to make glue. Some of today’s cements, such as Duco, are probably close chemical relatives.
Jetex articles in SAM35 Speaks told of another use for film. It was one of several experimental materials used for model rocket fuel. Film is extremely flammable, so it was a hazardous process getting the proper amount and shape packed into a little rocket canister.
The cross-section of a modern (full-scale) solid rocket motor normally features a hollow star-shaped core. It burns from the inside out. If ignition started with a little round hole, there’d be little initial thrust, followed by exponentially increasing thrust as the burning core enlarged. The internal star shape can be designed to allow more uniform thrust or even greater initial thrust where it’s needed most.
The model rocket experimenters were faced with similar problems using film. They tried packing it into various rolled or accordion-folded cross sections. It must have been a slow development process, often resulting in one burned-up model per short flight.
I’ll conclude the biographical sketch of Fred Megow, which began in the October “Old-Timers” column.
Fred had developed his green cabinets of model supplies for display in retail stores. He soon needed help to resupply cabinets and continue his business expansion. He began enlisting friends, neighbors, and family as employees.
Sales were generally high volumes of inexpensive (by today’s standards) supplies and models. Typical model kits were in the 10¢ to 25¢ range. Balsa was cut in Fred’s basement in large quantities. Sawdust permeated the neighborhood and neighbors complained but, unlike today, there weren’t multiple agencies ready to shut down the operation.
It became a flourishing business run on a shoestring budget, basically from a home with neighbors’ garages rented for balsa storage. A draftsman and bookkeeper worked upstairs in the house while others ran the basement shop. Fred had salesmen out expanding territories in neighboring states, and began advertising nationally.
In the summer of 1933, Fred rented his first real factory space for $30 a month. There would later be other moves to larger spaces. The neighbors were no doubt much relieved. The final factory encompassed three stories plus a basement. Later in 1933, Fred gathered the confidence to quit his job with the school system.
The year 1935 saw Fred’s business expand to include European countries and Australia. Balsa propellers were an important part of kits because few young modelers could produce a decent-performing propeller for a rubber motor. Fred’s brother designed a propeller carving machine and his father produced millions of propellers as a subcontracter.
Quick-dry cement was produced and sold in 5¢ and 10¢ sizes. For a while, cement was included in Megow and other manufacturers’ kits. This was discontinued for the same reason kit collectors are often disappointed today—the cement often dried up before the kit was ever started.
Fred engaged a balsa buyer in South America and filled a warehouse with the largest supply of balsa logs in the country. In December 1941, the US entered World War II and the Navy needed that balsa for life rafts, so it purchased the lot. With balsa supplies gone, modeling changed drastically as hardwood, plastics, and even cardboard were used for kits.
Megow survived with various war contracts, but during the post-war years the business climate changed, and regulations came from all levels of government. Jobbers and middlemen shared more of the profits. In early 1949, with company revenue diminishing, Fred Megow liquidated the business and retired to Florida.
I’ve heard that during the Great Depression, sales of model aircraft kits were one of the healthier parts of the economy. Lindbergh’s famous flight excited the nation and barnstorming pilots still traveled the country. People looked up when an aircraft passed over. And most of all, model kit building was one of the more affordable pastimes. At least a portion of the Megow success story was fortuitous timing, when few other new businesses would have survived.
“Real” Old-Timer (OT) models are built over plans on a flat building board. Many old plans show only one wing and sometimes one stabilizer. Instructions were to build one wing, then reverse the plan and oil it, making it semitransparent, to build the other.
That messy idea did have some merit besides cost savings. Mechanical drafting could produce plans with asymmetrical right and left wings. I avoided the oil mess by putting plans against a window and tracing onto the back side. Today a copy center can make reversed copies while giving you fresh plans in any scale you’d like.
Rubber modelers often shape propeller blades from thin, moistened balsa wrapped around cylindrical objects. This clever idea came from a SAM35 Speaks issue. By wrapping the propeller blades around a conical object you can make progressively pitched propellers.
One source of conical shapes is inexpensive miniature traffic cones used in field games and found in sporting goods stores. The propeller’s outer tip is placed toward the cone’s large end. Wider cone angles produce greater pitch progression. Positioning the blade closer to the cone’s tip produces greater curvature.
Snug pull-pull controls on RC models can strain servo bushings or bearings. More strain is produced when someone holds an OT model for launch by gripping around those lines. The servo strain can be eliminated by installing an idler bellcrank a few inches aft of the servo. Use a regular pushrod between the servo and bellcrank and run the pull lines from the bellcrank to the control surface. The bellcrank should be sturdily mounted and bushed.
One objection to diesel engines is the permeating fuel odor. Lava soap has been recommended as the best for getting the odor off your hands. And OxiClean is the recommendation for clothing.