Dynamic Propeller Balancing

How to keep the Cessna 170 flying and airworthy.

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Bruce Fenstermacher
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Re: Dynamic Propeller Balancing

Post by Bruce Fenstermacher »

Tom, you blew your cover. :roll:
CAUTION - My forum posts may be worth what you paid for them!

Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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bgiesbrecht
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Re: Dynamic Propeller Balancing

Post by bgiesbrecht »

Thread resurrection!

I just did this yesterday. Dynamic balance with a full spectrum analysis. I had meaningful vibration and my flying buddies were all getting their props balanced with amazing results.

My starting IPS was 1.5! 8O The first washer placement brought it down to 0.8 and what a difference. After some back and forth we got it down to about 0.4. I can’t believe the difference felt. Worth every penny.

The spectrum analysis indicated about 0.4 from the middle, so something slightly amiss with a plug, etc. Will be checking those this weekend...but I can barely feel it.

If you have any vibration at all, highly highly recommend doing this.
Former owner of:
1953 170B
N1977C
s/n 26122
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canav8
Posts: 1006
Joined: Thu Sep 25, 2008 2:34 pm

Re: Dynamic Propeller Balancing

Post by canav8 »

bgiesbrecht wrote:Thread resurrection!

I just did this yesterday. Dynamic balance with a full spectrum analysis. I had meaningful vibration and my flying buddies were all getting their props balanced with amazing results.

My starting IPS was 1.5! 8O The first washer placement brought it down to 0.8 and what a difference. After some back and forth we got it down to about 0.4. I can’t believe the difference felt. Worth every penny.

The spectrum analysis indicated about 0.4 from the middle, so something slightly amiss with a plug, etc. Will be checking those this weekend...but I can barely feel it.

If you have any vibration at all, highly highly recommend doing this.
I hope you meant 0.04 IPS. 0.4 IPS is still high. Most guys can get it down to 0.07 with not to much trouble if they have experience. I guarantee 0.07 if the prop can be balanced. I have had 2 props that I could not balance. One was because the owner had a cracked #4 cylinder and the other one was a prop that had a bent blade on a Howard. The owner finally admitted he bumped into his prop when parking his RV camper in the hangar. The hardest prop balance I ever did was an Italian 4 blade composite on a Suburu Legacy 6 cylinder. It took all day but I got it down to 0.02 IPS. I have never been able to balance one to 0.0 IPS yet. About 40 props now. Also I am finding that insurance is now requiring Dynamic prop balancing on claims.....YMMV Doug
52' C-170B N2713D Ser #25255
Doug
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