Ola Fremming's homepage

How to make room for long pipes

Quite a few of us F3A pilots do like the simplicity of the 2-stroke engines.  Many of the models that are available are designed for the use of a YS 4-stroke, and both the light weight and lack of room for the big muffler of 2-stroke engines, can be a problem when trying to use one in these designs.  Basically there are two solutions to this dilemma, one is to make the available space for the pipe/muffler bigger, the other is to reduce the space occupied by the pipe/muffler.  Below are some pictures of both solutions.

Extension of the available space

The extension is molded on the outside of this Monocote-covered plug of balsa.

The extension is glued in position with CA, and a mixture of epoxy and micro-balloons from the inside of the fuselage.

The long Greve-pipe in position in my Alliance.  The need for the extension is quite obvious.

Reduction of needed space

My friend Martin Omholt came up with this neat trick to reduce the length of a Hatori 900 (original for OS 140RX).  The original stinger is plugged, and a new one is inserted at the angled rear part of the pipe.  It is all done with special soldering for aluminum. The soldering is not easy, but with some practice it is possible.