Is a prop balance worth the effort?

[helitim]

Flight,

My recent firewall forward overhaul was complete and a new vibration was present that came w the overhaul.  I felt that the prop overhaul and subsequent removal of the previously placed weights were to blame.  The plane was flown down to Watsonville for Specialized Helicopter to work their magic.  The initial reading was 0.6 IPS.  The final reading was 0.02 IPS.  It's like flying a different plane now.  To anyone who has not had their prop balanced or doubts the value of it, I would say you should seriously reconsider.  A properly balanced prop eliminates vibrations that can cause unseen damage to the prop, spinner, bulkhead, engine as well as translate thru the entire airframe if the imbalance is bad enough.  For $200 I feel this is money very well spent.  Just my .02 cents, or in this case $200 worth.

Tim

[bonal]

Sounds good do they do eddy current inspects as well I have one coming up soon

[helitim]

250 quid!  That's almost $400 US.  Not going to complain about our costs if that's what it takes to fly over your way.  

[helitim]

3 hours ago, bonal said:

Sounds good do they do eddy current inspects as well I have one coming up soon

Not sure but, my A&P IA has an Eddy current machine at KLVK if that helps.

[wishboneash]

Tim, thanks for your reference. I went down today to Watsonville and got the prop balanced. My initial reading was 0.56 IPS and 3 iterations later, Bruce's technician brought it down to 0.01 IPS. Very smooth flight back. 

[Mcstealth]

On March 21, 2016 at 4:15 PM, Hyett6420 said:

I have to agree.  I pebble dinged my prop on a stone and whe the prop was dressed afterwards, the vibration was not good.  I had a dynamic balance carried out for 250 quid at Elstree and the vibration dropped to 0.02ips, almost as smooth as a babies bottom.  

 

Definitely worth the money.  

I like my quid dipped in a light tempura batter and fried till golden.  

[rbridges]

4 hours ago, Hyett6420 said:

The general rule over here is, whatever the cost in dollars, will be the same  "figure" plus a bit in pounds or Euros.  We have to pay for all our social benefits you see, like the beggars in social housing wanting a free handout.  Ok I'll get off my soap box now.  

Oh oh I forgot to say, I am very very impressed you know what a quid is.  

I don't understand your reference.  We don't have any freeloaders in our country.  (that is a ton of sarcasm)

[Shadrach]

The very fact that the 2 of you get to spend time soaring above the Proletariat in your private money machines means that those poor souls are entitled to a share of your labor whether it be intellectual or physical.  The Commissar is listening...

[MARZ]

not to detract - but with the mention of the eddy current inspection.....  I just had a top end and while the prop was off decided it should go in for a look see / rebuild   2900 dollars later - I have a rebuilt, AD free propeller.  I think the next step will definitely be a  dynamic balance.

[Mcstealth]

11 hours ago, Hyett6420 said:

Well if you want to burn Her Majesties currency and commit treason in the process, feel free .  Oh it's still a hanging offence over here, lol

 squid. I like my squid.....

my Texas sense of humor I'm sorry to say. Yes. Some of us know and eat squid!!!

[Seth]

Yes Yes and Yes again. I had the prop dynamically balanced on my Missile yesterday - Tuesday - at Senswich or however you spell it at Lancaster, PA, LNS while I was in town meeting with clients.

 

My airplane is SO smooth now compared to where it was.  I dialed the prop back on the way home and watched my efficiency increase.  Very happy with the result and the entire power train is now vibrating a whole lot less, and thus there's less stress there as well as the airframe over time.

 

I plan to do this every two - three years or 500 ish hours.

-Seth

[carusoam]

Nice Pirep, Seth!

best regards,

-a-

[wishboneash]

I found that the videos taken off the wing-end mounted GoPro camera are noticeably more stable after the prop balance (I used to have these low frequency resonance oscillations at lower RPMs). 

[FlyWalt]

20 hours ago, Hyett6420 said:

You've got Trump haven't you. Didn't he free load of his Dad, PMSL.

Well, the Clintons have been freeloading off of everyone's Dad in the US since Bill got into the White House the first time. So what is the difference.

[Browncbr1]

I got mine balanced last year.. It was at .07 or so if memory serves... they got it to .04...  I noticed that the plane was just generally more comfortable in cruise.. next time I do it, I'll insist to get it down to .02

I paid $250.. even at .04, well worth it.. 

[DonMuncy]

Please don't. I read all the MS posts and it burns too many of my ever diminishing brain cells sifting through politics.

[jclemens]

.07 IPS is where my ACES 2020 unit "gives up".  Balancing to anything less than that is just a guessing game.  I seriously doubt if the vibration level is detectable by a human being at a level lower than that.  Most props start around .30, .07 is a very noticable improvement.

[helitim]

7 hours ago, Browncbr1 said:

I got mine balanced last year.. It was at .07 or so if memory serves... they got it to .04...  I noticed that the plane was just generally more comfortable in cruise.. next time I do it, I'll insist to get it down to .02

I paid $250.. even at .04, well worth it.. 

If they got it down to .04 and it wouldn't go any lower, you might consider remounting your prop 180 degrees and rebalance.  Anything below .1 is considered acceptable though.  

[Browncbr1]

yea, .07 felt ok, but .04 was a noticeable improvement in cruise comfort..  without a doubt.  Once it read .04, he stopped.. he didn't try to improve it further because he said it is diminishing return on time... He said he could probably get it down  to .03 or .02, but it would take another hour of hassle...   we had already run it 4 or 5 times and been fiddling for about 2 hours..   next time i'll insist to keep going.. 

[RobertGary1]

On 3/23/2016 at 7:55 AM, daver328 said:

Tim, 

bonal, 

for about 1 AMU you can have your hub modified to remove the eddy current inspection AD. I heard from our prop shop it was very labor intensive, thus the fairly high cost. They basically modify the hub to hold red oil that would become evident in the event of a crack in the hub (like McCaulley) ... still it's way cheaper than a new prop or new hub! 

..

I skipped it. The AD no longer requires the ECI at annual so its only every 100 hours. I have enough toys to fly that the Mooney will probably take 4+ years before its ready for the next. So my break even point is probably 20 years out.

 

-Robert

[Hank]

On March 23, 2016 at 3:26 PM, Hyett6420 said:

I just eat meat, you must be very poor to only be able to feed on a bottom feeder. . Ps that is NOT a gay reference, before anyone gets upset.  

A little fried squid is a great appetizer before tucking into a large piece if beef. Or a roasted duck. Don't have any upland birds available down here, unless Nobodyndrops in for a visit. 

Relevant Question:  I know my prop has been balanced at some point in the past (Hartzell 3-blade). It was before I bought her in 2007. Is this really something that should be redone periodically? How can the balance change if the prop isn't losing any material? No nicks, no dressing, still pretty smooth leading edges. Cody???

[Seth]

On March 24, 2016 at 2:08 PM, Browncbr1 said:

I got mine balanced last year.. It was at .07 or so if memory serves... they got it to .04...  I noticed that the plane was just generally more comfortable in cruise.. next time I do it, I'll insist to get it down to .02

I paid $250.. even at .04, well worth it.. 

Wow.  Mine was WAY Way more than that and got it down to .03.  Huge difference.  PM me and I'll let you know how bad.

-Seth

[Seth]

46 minutes ago, Hank said:

A little fried squid is a great appetizer before tucking into a large piece if beef. Or a roasted duck. Don't have any upland birds available down here, unless Nobodyndrops in for a visit. 

Relevant Question:  I know my prop has been balanced at some point in the past (Hartzell 3-blade). It was before I bought her in 2007. Is this really something that should be redone periodically? How can the balance change if the prop isn't losing any material? No nicks, no dressing, still pretty smooth leading edges. Cody???

I was told yes - every 500 hours or so, vibrations and harmonics cause things to move.  Think of it as an entire engine/powertrain balance.  Or at 2400 RPM you are moving st .24 inches per second but the rest of the ranges, 2500, 2300, 2200 are all around .04, then you now have an indication of an internal engine issue, like a cam love or lifter issue.  

Also, the prop cal be set for your preferred cruise RPM, to ensure you have the least amount of vibration where you'll cruise most.

I'm curious what Cody says as well, but after my recent results, I'd get my prop dynamically balanced if it's been 10 years.

-Seth

[RobertGary1]

It might depend on your engine. I've always run the A3B6 balanced Lycoming so vibration isn't a big issue. But I could see a balance helping more with the older A1A. 

 

-Robert

[Cody Stallings]

Your aircraft can get rougher( dirty plugs, old mags, droopy lord mounts, ect) an it's not always the prop that is the problem. But the prop is where you go to fix it via dynamic balance every time.

Its the only thing spinning on a plane that can be manipulated balance wise.

Should a prop be balanced every couple years? Yes Sir!!!!

Over time, your going to slowly get use to the small vibrations. Small vibrations that slowly get worse.

Bearing in your engine, Avionics, Exhaust, Intake tubes an Rivets all feel it better than you do.

With that being said, I have seen several props all Hartzell's have issues with vibration after being serviced. 

When you put more grease in one side of the prop than the other! It's very common