Dynamic Prop Balancing

[FlyingMonkey]

Has anybody had a prop dynamically balanced on a CT? It supposedly makes a world of difference on any airplane, and my CT seems pretty "vibey"...

[FlyingMonkey]

Next question...anybody know a shop in the ATL area that is good at balancing props for a reasonable cost?

[Adam]

Before balancing (I defer to Roger that its a good idea) I wonder if you have set the pitch? I have found (even on new planes just delivered) that the prop pitch being off a few degrees between blades causes vibration and mediocre performance issues. Many threads already in existence here about wide open throttle (wot) desired RPM settings in straight level cruise flight. I was amazed at the difference in performance of my bird that was experienced just by making sure pitch was identical on all three blades and then all three set for wot in cruise flight. (others will opine on best RPM, I go for 5300 myself)

[FlyingMonkey]

Before balancing (I defer to Roger that its a good idea) I wonder if you have set the pitch? I have found (even on new planes just delivered) that the prop pitch being off a few degrees between blades causes vibration and mediocre performance issues. Many threads already in existence here about wide open throttle (wot) desired RPM settings in straight level cruise flight. I was amazed at the difference in performance of my bird that was experienced just by making sure pitch was identical on all three blades and then all three set for wot in cruise flight. (others will opine on best RPM, I go for 5300 myself)

 

Pitch is set the same for all blades, at least to the limit they can be the same.

[Ed Cesnalis]

I think most shops that do balancing don't want to balance a CT because the spinner bulkhead is composite.

[FlyingMonkey]

I think most shops that do balancing don't want to balance a CT because the spinner bulkhead is composite.

 

Hmm...interesting. I'll have to ask around. Is that where they typically attach the weights? Could they put them on the flat metal prop hub instead?

[Anticept]

Neuform props (at least on LS) do not have composite hubs. The hubs are two part metallic plates, anchored to the crank flange. These two plates bolt over the metallic root of the blades posessing circumcised recesses. These tubular roots have a narrow hollow core which might be where weights can be placed. I'm not sure.

 

There was a dead mouse found in one of my prop blades a while back. That was a surprise.

[Tom Baker]

I have seen one CT with a screw and a couple large area washers on the spinner backplate.

[Ed Cesnalis]

I have seen one CT with a screw and a couple large area washers on the spinner backplate.

 

I have had shops tell me they don't do CTSWs because they are reluctant to put screws in the spinner bulkhead and at least 1 guy that says he does it that way.

[Adam]

 

 

There was a dead mouse found in one of my prop blades a while back. That was a surprise.

 

How the heck did little guy get up in there? I bet he thought he had a great home until after a few seconds at 5000 RPM!

[Anticept]

It's apiece of cake. FD and others put weights and or screws on our type backing plates all the time. It's the others that are

un-informed. I have a balancer and it isn't that tough to do. FD uses screws as weights mounted to the backing plate. Mount it to the top lip or the back, either works.

 

I might ask you about the balancer that you have. We've taken the prop off and apart for an engine change, and I'd really like to make sure I haven't thrown it out of whack.

[Runtoeat]

I had my prop ballanced. Don't understand the concern of where to put the offsetting weight. Just added the right diameter and thickness washer to the prop bolt (C9996260) corresponding to the light spot. Ballancing made a noticeable difference. Adam's comments about insuring the pitch is same for all blades is correct. I set all blades to within .1 degree of each other with a fixture I made which accepts a digital protractor. This made a difference similar to the improvement I got by ballancing.