Hit & Miss engine kit little Karl

The combustion engine “Little Karl” is, as the name suggests, the small version of our popular combustion engine Karl. With this kit, particular emphasis was placed on the fact that it can be made in a small hobby workshop with a small lathe. Thanks to its simple construction, this model is also suitable for beginners in technical model making. In contrast to the large stationary engine Karl, this model does not have an ignition with a spark plug but rather a Glow plug. This circumstance makes both the construction of the model and its operation easier because the ignition timing does not need to be adjusted. Of course, this model also has speed control via Hit & Miss control.

The combustion engine “Little Karl” with glow plug has a stable frame made of milled brass parts. The crankshaft is guided in two gunmetal plain bearings. The cylinder sleeve consists of a precision brass tube that no longer needs to be processed inside. An aluminum piston runs in the tube. The cylinder head and cooling jacket are also made of aluminum. Most other components such as the carburettor, tank, rocker arms and controls are made of brass. The entire motor is mounted on an aluminum base which in turn rests on two oak wooden runners. The two 80mm flywheels and the pulley are made of cast steel using the lost wax casting process and are of excellent quality. All materials required to build the combustion engine "Little Karl", such as screws, springs and ignition parts, are included in the kit. All milled parts are prepared so that they only need to be deburred and possibly drilled. All turned parts are included in the kit unmachined and must be manufactured according to the drawing.

To build the Hit & Miss Motors requires a small lathe, a drill and a gas burner for soft soldering. The following hand tool is also required (tap M2, M3, M4, tap UNEF1/ 4 x 32, Dies M4, M6, reamer 3H7, 5H7, 6H7, 8H7) files and a drill set are necessary. All you need to wire the glow plug is a pair of side cutters, wire strippers and a soldering iron. You also need a baby battery with at least 3000 mAh. The battery is not included in the kit but can be ordered from us.

If you would like to find out in advance which work steps you have to carry out when manufacturing this combustion engine, take a look at our Bengs model building magazine Construction report of the combustion engine "The Little Karl" with glow plug. On this page you can see the illustrated report on how the stationary motor material set is processed.

Dimensions of the model combustion engine 'Karl':

• Height with wooden runners: 135mm
• Length overall: 200mm
• Width overall: 120mm
• Length without runners: 190mm
• Piston diameter: 20mm
• Flywheel D.: 80mm
• Speed: 600-1500 rpm
• Weight of the finished model: 1.8kg

Hit & Miss Regulation

With the hit & With this control you can limit the maximum speed of the engine. If the engine has reached too high a speed, a slide prevents the exhaust valve from closing. This means the engine runs freely. No compression can occur in the cylinder chamber and the engine neither sucks in fresh gasoline nor ignites the air-fuel mixture. The Hit & Miss regulation is called suspension regulation in German. The misfire control was mainly used in the USA by various companies for internal combustion engines from 1890 to 1940.

The scope of delivery includes:

• finished CNC milled milled parts
• Raw material for the turned parts
• Rough casting part for the flywheels 80mm 
• Raw casting part for the belt wheel 
• Two wooden runners made of oak 
• All required screws, nuts, gears and sealing rings 
• Drawings of the combustion engine "Little Karl" (24 sheets) and construction instructions (11 sheets) 
• Switch, battery compartment, cable and glow plug (Battery Baby battery not included is available from us