Dynamic prop balance - worth it?

[Slick Nick]

I’ve got my prop coming off at annual here for a warranty re-seal (it was just overhauled last year and one of the blades started weeping.) I haven’t noticed much in the way of adverse vibrations thus far, but is the cost of a dynamic balancing worth it when the prop is reinstalled? I typically run at either 2500 or 2400 rpm depending on if I’m doing a best power or Econ cruise. If I get it balanced to a specific RPM, say 2500, will that make a noticeable difference when I choose to run 2400? 

I fly a lot, and as I mentioned I haven’t really noticed much vibration as it is, but if it’s something I’m missing out on I’d definitely go for it. A smoother running engine is good for longevity. 

Would love to hear some feedback, good or bad, if it’s worth it. McCauley C214 2 blade on a ‘91 J model. 

[mike_elliott]

yes

[Hank]

Yes, dynamic balancing is worthwhile. 

[Pinecone]

Another yes.

Vibration is bad for most components and actually the airframe itself.

[Paul Thomas]

Lower RPM have higher amplitudes. 

[MikeOH]

Yes.

[EricJ]

A buddy was having one of our local prop balancing guys do his airplane, so while he was here I had him do mine, even though I didn't really have any complaints.    He said mine was pretty good to start with, but he did manage to get it better.   On his instruments it wasn't a huge change (I don't remember the numbers), but it was a difference.   Interestingly, even that small change was noticeable in the airplane.   It really did make a noticeable difference, which I thought was pretty cool.

[FlyingDude]

Yes, I do dynamic balancing (as an a&p) and every single one of my customers said they could feel the difference. 

[dkkim73]

Any opinions on rebalancing after changing cylinders? (3 since balancing after prop overhaul)

[GeeBee]

23 minutes ago, dkkim73 said:

Any opinions on rebalancing after changing cylinders? (3 since balancing after prop overhaul)

Yes, do it. I just had mine done last Friday. I usually do it every 3 years or 500 hours whichever occurs first. I was talking with the shop about changes that require re-balance and changing cylinders is one of them.

[Bolter]

(on my former J) I also thought nothing of my vibration levels, but was convinced by my A&P to let him do it.  Sure enough, it was a seat of the pants measurable difference, for all of my typical operating speeds.  I do not think that balancing for 2500 rpm means that 2600 and 2400 rpm will be rough as a trade off.

I do not think I have heard anyone complain that balancing did not make an improvment.  

[Hank]

1 hour ago, GeeBee said:

Yes, do it. I just had mine done last Friday. I usually do it every 3 years or 500 hours whichever occurs first. I was talking with the shop about changes that require re-balance and changing cylinders is one of them.

What is your rationale for this? 

I had mine checked at annual in 2018, having been done during overhaul by the previous owner around 2003-04. It was still under 0.01 ops. Haven't checked it since.

[GeeBee]

1 hour ago, Hank said:

What is your rationale for this? 

I had mine checked at annual in 2018, having been done during overhaul by the previous owner around 2003-04. It was still under 0.01 ops. Haven't checked it since.

Prop blades erode, sometimes you have to dress out nicks and if you have de-ice boots so do they. Mine did not change much but it did change. 

[Slick Nick]

Thanks everyone for the input! I’ll be getting it done 

[TaildraggerPilot]

It’s worth every penny, as long as the pennies don’t add up to more than $425

[hubcap]

Definitely worth it in my opinion. I noticed the biggest difference in cruise, not so much in the pattern or climb.