Testing 66mm cast wheel from aliexpress. Engine ran up to 95000 rpm before the fuel pump ran out of ooomph. Fuel pump with higher pressure is needed. 3kg thrust at 0.65Bar and 95000 rpm.
@@nicolasm7012 The homemade wheels had some issues with the geometry. I bought a cast wheel and compressor for a kj66 i am going to build and I am testing this wheel to eliminate turbine issues.
@@nicolasm7012 this engine has its shaft critical frequency at 135000 rpm. Thomas kamps writes in his book that 20% margin of safety is needed. This gives 108000 rpm. I guess less margin is needed in the air when the engine is far away from people.. Yesterday i found that my preloading system (built as designed) is wrong with this wheel. Preload spring is in the rear. Dynamic force is pushing the shaft forward and unloading the preload on the front bearing. Front bearing is now in bad condition. I will make a solid spacer bushing for the rear and preload the front bearing instead.