Stinson Junior (oz14352)

About this Plan

Stinson Junior. Radio control scale model.

Quote: "A sport scale beauty from the Golden Era of Aviation; for .40 4-stroke engines. Stinson Junior, by Terry L Moore.

In 1928 Eddie Stinson first produced the Stinson Junior, the smallest of his designs and basically a scaled down 3/4 seat Detroiter, under the desiignation SM-2. This was initially powered by a 110 hp Warner Radial engine, with which its performance was modest to say the least.

Consequently, when the SM-2A Aversion entered production at Stinson's new plant in Wayne, Michigan, it was powered by a 5 cylinder Wright J5 of 165 hp and 22 were built. This model was superceded by the SM-2ABD with a 220 hp Wright .15 which gave a considerable increase in speed and included a better standard of internal fittings…

The current survivors of these 1929/31 aircraft are frequently found to be hybrids, incorporating non-standard combinations of flying surfaces, cabin windows, etc. Although I have accurate scale drawings of the SM-2 Model S and Model R. there are an infinite variety of 'in-betweens'.

The subject chosen for my model is just such a hybrid. Basically it is a Junior S2, with Model S tail surfaces plus undercut rudder as SM-2, an extra rear window each side of the cabin and a 7 cylinder radial. Detail photographs are available from Scale Model Research, 3114 Yukon, Costa Mesa, California 92626, (714) 979-8058.

Construction: To anyone familiar with built-up structures this should present few problems. To those more accustomed to the three 'F's (fiberglass, foam and film), welcome to traditional old-fashioned aeromodeling! This model is simply larger, slightly more complex Super 60 with added scale detail; an undercarriage of greater intricacy and dummy radial engine.

Subject to previous experience of built-up structures, the model is suitable as a first scale attempt, provided your flying has passed beyond low winged aileron training status, and you have some experience with taildraggers.

As ever, careful selection of balsa to suit location and sparing use of glue and paint is essential, as is accuracy of building and alignment of flying surfaces, thrustlines, datums, etc.

The following is not intended as a step by step instruction manual, but simply highlights areas of particular care or unusual methods of construction (of which there are few).

Wings: Make a master rib template from 1/16 plywood and cut out all ribs for both panels, Sandwich together on the 1/2 x 1/4 in main spar and sand for uniformity. Check that the joiner tube holes are aligned together front and back. Care is needed to arrive at the correct wingtip section using block infill. Remember to tilt the root ribs to suit 1-1/2° dihedral. The ailerons are cut out after overall wing construction. The joiner tubes lay appear short, but remember, the struts are functional..."

Direct submission to Outerzone.

Scan by MarkD, cleanup by Circlip.

Update 31/1/2023: Added alternate article, from RCMW, thanks to Pit.

Supplementary file notes

Article.
Article (RCMW).

Corrections?

Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction