Notes on the 5-Bears Website
|
Many engines builders who are interested in the plans for a model radial engine often comment on the 5-Bears website. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ I admire the work that 5-Bears has done on his radial engine, and his very nice website, however, please understand that he built his engine from plans available in 1998. Since that time, the plans I currently sell, have been revised to the point that the comments in the 5-Bears website are out-of-date. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Master Rod The plans have always specified an aluminum master rod. Building the engine with a steel rod is too heavy for the crankshaft counterweights, and will cause the engine to run with considerable vibration. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Electronic Ignition The 5-bears website has had information on the development of an electronic ignition system that gave considerable trouble. The current plans specify a very rugged CDI ignition system. ( See the supplier list ). This is a very rugged and dependable ignition system. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Improved Cam Currently, all of the engines have a cam with a constant acceleration lob profile. Six cams were tested over a two year period, before the optimum lift, and duration were developed. This cam design was not available in 1998. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Impeller & Seal Plate The rear of the crankcase has been re-designed to incorporate a real seal plate that separates the rear main bearing-mounted oil pump from the intake space. In addition, a 12 vane impeller running at crankshaft speed, leads directly to the intake pipes. This ensures complete atomization of the fuel. This improved design was not available previously. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Piston Rings The piston rings have been re-designed to lower running friction and provides more effective sealing than the previous design. Notes on the use of mineral oil for break-in are also included. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Please keep these improvements in mind when planning your radial engine project. Your set of plans will always include the most recent developments. Supplements are available for plans that were purchased previously.
|