Balanced the prop today

[sandpiper]

Today I had a dynamic balance done on my propeller. According to the guy running the equipment, the prop was not drastically out of balance but was in a range where balancing was indicated.

 

Apparently it came from the factory balanced. Not sure if that was for the spinner, backplate and prop or just for the spinner & backplate. Anyway, there was already a bolt with some washers installed on the backplate.  But, after 7 years and 380 hours, adjustments were needed.

 

Now it is smooth as a turbine in flight and on the ground. Well, maybe not quite but the improvement is noticeable. Definitely worth the effort. Maybe I should try some of that Jet A. :unsure: (joking)

[Runtoeat]

Hi John.  Also had my prop balanced a while ago.  This made a good difference but I still noticed vibration during quartering winds while on the ramp or if strong gusts hit my prop during idled engine low speed coasting in the air.  I found my gear box was at the low end of the spec for "torque to turn".  I sent my my gearbox to LEAF for rebuild and this eliminated the vibration.

[FastEddieB]

...but I still noticed vibration during quartering winds while on the ramp or if strong gusts hit my prop during idled engine low speed coasting in the air. 

 

I think both of those issues are more related to disturbed airflow over the prop than balance, per se´.

[Anticept]

Props are statically balanced at the factory to extreme precision. Installation and aircraft nose shape introduce error in the balance, which is why you want a running dynamic balance. Just make sure you put marks on the prop, spinner, bulkhead, etc before you remove them, as it is vitally important that you keep these all in the same order on reinstallation, or you could make the problem much worse, especially if it were reinstalled in the 180 degree phase.