Popular Science Monthly 



471 



An Outboard Motor Made of 

 Pipe and Fittings 



A SERVICEABLE and satisfactory out- 

 board motor for a rowboat can be con- 

 structed from a second-hand motor-cycle 

 engine and ordinary pipe and fittings. 

 Either the one-cylinder or a "twin" motor 

 can be used, the only difference being in the 

 mounting, which can be worked out by an 

 amateur mechanic. 



While the stern transoms of rowboats 

 vary somewhat in size, the dimensions 

 herein given will suffice for the average 

 boat. Any increase or decrease in the 

 length of the upright supporting the motor 

 can be adjusted by varying the length of 

 one of its sectional parts, as shown in the 

 drawing. 



There are two essential parts to its con- 

 struction; the 

 motor and pro- 

 peller frame and 

 the supporting 

 board. Sections 

 A, B, and C are 

 made of i^-in. 

 pipe. The parts 

 D and E are the 

 same size cross 

 tees while F is a 

 \ x /i-\n. coupling 

 with a J/£-i n. 

 threaded opening 

 in the side at G. 

 Thetotaldistance 

 from the flange 

 H to the bottom 

 of E should be 

 sufficient to im- 

 merse the pro- 

 peller-blade at 

 least 3 in. under water, and the distance 

 from G to the center of E must be at least 

 6 inches. 



The propeller / should be not over io in. 

 in diameter and of shallow pitch, to allow 

 for the usual high speed of motorcycle 

 engines. This is connected with a tool 

 steel shaft revolving in the proper bushings 

 in E. The other end of the shaft carries a 

 large sprocket wheel /. 



The rudder hanger K is made of 3^-in 

 piping by means of two straight pieces and 

 an elbow. Fit the lower end with a tee to 

 receive the bottom rudder-peg. A cor- 

 responding piece of 3^-in. pipe is threaded 

 into G. 



Thread a small hole in one side of E and 



The parts in detail for making and attaching a motor- 

 cycle engine to a rowboat for an outboard motor 



fit with a thumbscrew, then bore a 3^-in. 

 hole about 2 in. under the flange on A and 

 through the side of the pipe. 



The mounting of the motor must neces- 

 sarily be left to the builder, as each of the 

 varied types and makes of motors must be 

 mounted in its own way. The semi- 

 circular strap shown in the drawing can, 

 however, be adapted to several different 

 standard makes. In any case be sure that 

 the small sprocket M is lined up with / 

 and that the crankshaft is long enough and 

 pinned, to accommodate a starting handle. 

 The rudder N can be cut out of heavy 

 galvanized sheet iron and riveted to the 

 rudder rod 0. This rod extends up as far 

 as the base of the motor and is connected 

 with the tiller by an elbow. The tiller is 

 swung off at an angle so that it turns 

 either way to clear the motor ancf frame. 



Connect the 

 two sprockets 

 with a light 

 motorcycle chain 

 and cover well 

 with heavy 

 grease. 



Thesupporting 

 board can be 

 made of a piece 

 of heavy oak 18 

 in. long and 12 in. 

 wide. Curve the 

 top edge to con- 

 form with the 

 curve on the edge 

 transom. 



Have a black- 

 smith make two 

 heavy iron brack- 

 ets P and Q and 

 fit the short ends 

 with thumbscrews as shown. Bolt one 

 bracket to each end of the board, counter- 

 sinking the bolt-heads on the underside. 

 The smaller brackets, R and 5 should be 

 sufficiently heavy to hold the motor and 

 frame by means of a steel pin passing 

 through the holes in the ends of the 

 brackets and the hole in the pipe A. 



Bend a short piece of i-in. pipe so that 

 the curve will equal the arc made by 

 swinging the suspended motor frame back 

 and forth on the pin. Then secure the 

 pipe to the board by means of a wide flange 

 so it will travel through E. The motor can 

 be held at any point along T by the thumb- 

 screw, according to the pitch of the 

 transom. — L. B. Robbins. 



