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Prop vibration solved.

Storch

Member
We bought our 10 with 150 hours on it. IO-540D4A5, two bladed Hartzell HC-C2YR-1BFP/F8068D.
It has had that nagging slight vibration since completion.It follows the engine RPM,gets worse at lower RPM. We put an additional 350 hours on it in the last couple of years. We read all the posts, did all the usual magneto timing, chaffing inspection, prop balance twice, retorquing of everything, etc. Nothing worked.Fortunately we found Les Doud, [email protected], and he suggested reclocking of the prop.
But as most of you know this engine-prop combination will not allow the prop to be moved at all (because of the physical location of the bushings-the prop will not receive them due to their differing lengths). Les sent us the Lycoming crank flange bushing guideline, with the stock location and the desired reclocked location of the bushings and their respective Lycoming part numbers. We ordered the bushings from AC Spruce, it took about a month to get them.
Now for the big news. You cannot remove and install the bushings without a special tool. We tried all the homemade remedies. There simply is not enough clearance between the backside of the crankshaft flange and the engine. I finally located the tool at Lycoming. Its a ST-115 (Special tool). They will not sale it or rent it to you but Van Bortel-Air Power will because they are an authorized Lycoming dealer. I called them, gave them the part number and it was at my place in a few days. Costs-they charged me $1354.00, but refunded it when I returned the tool. Rental cost-$100 per month plus shipping. The tool makes it a snap.We did have to use a long socket and an AN 6 bolt on one or two of the bushings to start them. Very obvious and simple. Entire project can be done in less than a day.
We reclocked the prop so that with #1 at TDC, the prop is horizontal. The prop only needed to be moved one hole. Previously it was at the traditional 11-5 position for hand propping.
Smooth as silk.
 
Kudo's for Les Dowd

My story is identical to yours. And the path sounds identical including two dynamic balanceing's, and lots of research, then Les. My experience was about 10 years ago with a Super Six. I am surprised not more people have talked about reclocking their IO540.

Steve
 
I had the exact same problem, although I have an IO-360 with a WW RV74 prop. Balanced twice, everything else you can think of. A friend suggested re-clocking the prop. Fixed instantly. Never been smoother.
 
Thanks for sharing your experience! I am still far away, but does it mean this prop & engine combo should be installed this way by default?

Thanks,
 
I understand that you had a positive result with your re-clocking. But I don't understand the physics on why this was a solution. I would have thought that a balanced prop wouldn't have made any difference. Can you elaborate more on the details on how you or Les came to this conclusion?

thanks,

bob
 
The prop wash from the blades hitting the wing roots could cause enough "thump" (I'm guessing here) that if it was in resonance with an existing engine first-order vibration it becomes noticeable, but if it's out of phase it is not?
 
I don't recall the conversation exactly, but I have a friend who was a member of the "core" engineering design group for several OEM engines.

We got to discussing crankshafts, including why/how you can get a crank failure by taxing into high grass.

Possibly related to the above is the several "orders" of crank vibrations (think bending) that exist. It may be the location of the mass in conjunction with what the crank is doing (because of firing impulses and shape of crank) that leads to this "Phenomena"

FWIW
 
Vibration resolved.

I understand that you had a positive result with your re-clocking. But I don't understand the physics on why this was a solution. I would have thought that a balanced prop wouldn't have made any difference. Can you elaborate more on the details on how you or Les came to this conclusion?

thanks,

bob
Bob,
The prop balance(s) did not work. I sent Les the spectrum plot data card from the balance and he deduced, correctly, that it was a 1/2 per revolution vibration. After balancing, the prop was at .01 IPS, nearly perfect. So there is nothing wrong with the prop. I had even sent the prop back to the shop for an internal inspection. More wasted money.
There are tons of smart guys who have very in depth engineering-physics backgrounds who have posted very complex explanations for why this phenomena exists. In 40 years of working on airplanes I had never experienced it. It simply does not seem to make sense.

But it does exists and the solution works. Thanks Les and the folks on this site who helped!
 
Vibration thump

The prop wash from the blades hitting the wing roots could cause enough "thump" (I'm guessing here) that if it was in resonance with an existing engine first-order vibration it becomes noticeable, but if it's out of phase it is not?

During this grand adventure, I did discover a very pronounced "thump" type vibration. I have a basic interior with no side panels so it was easy to find. It is located on the side wall where the copilots right knee touches the side wall of the fuselage. Very noticeable in flight when you place your palm on this area. I affixed a sheet of ABS plastic with some heavy duty Velcro and it helped. Probably a 2024 doubler would be better.
 
Clocking

Can't offer a scientific reason for why this works but Mooney issued service bulliten M20-206 to reclock the prop 60 deg backwards. This was for the 201 models with counterweighted Lyc IO-360s. It states that it doesn't change the engine vibration level but does make it less noticeable in the cabin.

Don Broussard

RV9 Rebuild in Progress
57 Pacer
 
Advice?

..so, for us guys who haven't yet ordered or installed our engine and prop combos yet, is there something we can do to make sure the engine prop combo we buy is "correctly" clocked? You mentioned that the original setup you had was clocked to allow hand-propping. Is there a way to specify that an engine be set up properly for the 2-bladed Hartzell combo? When ordering a new prop and engine together, can we be sure that it has been properly clocked, or is this something that the builder must do?
 
Storch,

Thanks for that post!
I've balanced my prop to .01ips and ran a few vibration surveys in flight with my balancer. My engine is smoother at 2700 than at 2360 rpm. I bought all new vibration mounts (i have the not so good VIP mounts, got Lord mounts now), but haven't installed them yet to see the difference.
My half order vibration in flight is .07ips at 2700rpm and .13ips at 2360rpm.
What kind of numbers were you seeing on your spectrum?
Check out the spectra below. The dotted lines are set at half order vibration.

Lenny

vibsurvey2700.png

vibsurvey2360.png
 
No.1 Crankpin identification

SI 1098G refers to No.1 crankpin from which all other bushing locations are referenced, but does not say how to identify this crankpin.
Is it marked on the prop flange? Something else?
Please help.
Thanks.
Johan
 
New Bushings

Hi Storch, I have the same problem that you had and want to re-clock my prop. Did you have to buy new bushings, or could you have used the old one's? I see they come in oversizes; how did ya know if you could use the stock size or oversize. Thanks Barry
 
For the people with an IO-360 and WW prop, the prop can be clocked in any position without changing the bushing. The oversized bushing positioned the flywheel, but will fit all the holes on my prop hub.

The best way I can describe the vibration I felt was a deep shake. Even though the balance came out to .04, then .01 IPS, I continued to feel the vibration. Was told the Grumman tiger needed to be clocked a certain position for the same reason.

The best reason we could figure out with the 4 cylinder engines is the highest load on the prop is on the downward movement. With the lightweight prop, it was accelerating when the pistons fire, then decelerates on the down pass. Caused a deep feeling shake.

Not an engineer, but it really made a difference on my plane. Once again, YMMV.
 
You cannot remove and install the bushings without a special tool. We tried all the homemade remedies. There simply is not enough clearance between the backside of the crankshaft flange and the engine. I finally located the tool at Lycoming. Its a ST-115 (Special tool). They will not sale it or rent it to you but Van Bortel-Air Power will because they are an authorized Lycoming dealer. I called them, gave them the part number and it was at my place in a few days. Costs-they charged me $1354.00, but refunded it when I returned the tool. Rental cost-$100 per month plus shipping. The tool makes it a snap.

Now I'm very curious... what does this super special tool look like?
 
What if you have a 3-blade prop? Is that immune form this phenomena or???

I remember that the early Cirrus had a vibration problem with the old 4-point engine mounts. Apparently that was solved with a 5-point mount IIRC.

~Marc


For the people with an IO-360 and WW prop, the prop can be clocked in any position without changing the bushing. The oversized bushing positioned the flywheel, but will fit all the holes on my prop hub.

The best way I can describe the vibration I felt was a deep shake. Even though the balance came out to .04, then .01 IPS, I continued to feel the vibration. Was told the Grumman tiger needed to be clocked a certain position for the same reason.

The best reason we could figure out with the 4 cylinder engines is the highest load on the prop is on the downward movement. With the lightweight prop, it was accelerating when the pistons fire, then decelerates on the down pass. Caused a deep feeling shake.

Not an engineer, but it really made a difference on my plane. Once again, YMMV.
 
Actually, Dayton has a Catto 3 blade prop, with an O-320 and told me about is. If I remember right, he had this problem also.
 
Vibration-bushing size

Hi Storch, I have the same problem that you had and want to re-clock my prop. Did you have to buy new bushings, or could you have used the old one's? I see they come in oversizes; how did ya know if you could use the stock size or oversize. Thanks Barry

I purchased new stock size bushings, a little pricey but good piece of mind. Never got a definitive answer on reusing them.I believe I recall the oversize being a greater O.D.- I assume that would be for a repair if the hole had been erroneously enlarged?? Not certain.
 
Vibration-crank pin

SI 1098G refers to No.1 crankpin from which all other bushing locations are referenced, but does not say how to identify this crankpin.
Is it marked on the prop flange? Something else?
Please help.
Thanks

Yes, I had the same question. I did not find any identifying marks. Try as we did to understand the location of the Lycoming 1098G "No.1 crank pin" we could not do it with absolute certainty. However with our new engine-prop clocking combination, the new placement of the bushings naturally fell into place.What we did was determine the physical location of where each new bushing placement (in the crankshaft flange) would be according to our new prop location.We did not have to change all the bushings. The new position of the prop allowed some of the existing bushings to remain in place. Then going by where the prop needed to be (in relationship to the crankshaft flange) we simply placed the bushings in the respective hole. To achieve the desired new reclocking position we only had to move the prop one hole counter clockwise as viewed from the front of the airplane looking aft. Thinking it through lead us down the this placement path and it worked perfectly.
It did require quite a bit of head scratching.
 
Actually, Dayton has a Catto 3 blade prop, with an O-320 and told me about is. If I remember right, he had this problem also.

I'm having a very similar problem with my 3 blade Catto. I went from a wood two blade to the Catto and I have heavy shaking at about 1400 RPM and not as smooth as my wood two blade at cruise. It was described above ad sort of a "thumping" and that is what I feel. I have clocked the prop, and even sent it back to have it reworked by Catto and still the same.

The Catto's are building me a whole new prop now, and I'll have it in a few weeks. less wood, more carbon this time. Hopefully that will do the trick.

Let me add- Nichole at Catto has been very patient with me and at a whole, very accommodating. I have been told by others that they want happy customers, and they are trying very hard to make sure that I am!!

I'd like to know the outcome of "Dayton" above.

PS: sorry about jumping in with my issue...
 
Vibration-clocking

..so, for us guys who haven't yet ordered or installed our engine and prop combos yet, is there something we can do to make sure the engine prop combo we buy is "correctly" clocked? You mentioned that the original setup you had was clocked to allow hand-propping. Is there a way to specify that an engine be set up properly for the 2-bladed Hartzell combo? When ordering a new prop and engine together, can we be sure that it has been properly clocked, or is this something that the builder must do?

When I refer to hand propping-it's the typical position nearly all two bladed props stop at. Just like a J-3, easy position to hand prop. I assume this is a carry over from the old days. Again, my experience is I've never heard of this phenomena prior to our 10. Nobody I talked to in the aircraft industry including Vans, except Les Doud and some folks on this site, had ever heard of it. It seems the stock factory position is ok the majority of the time.
 
Prop position for hand propping

When I refer to hand propping-it's the typical position nearly all two bladed props stop at.

Stopping in the 10-4 o'clock position is only true for 4 cylinder engines. The 6 cylinders have another position (about 2-8 o'clock) position where it will stop. 4 cyl crankshafts can be laid flat (all journals in same plane). 6 cyl cranks are triangular geometry.
The OP has 6 cyl engine.
Johan
 
Any idea how he chose one position clockwise as correct or was the plan to start with that?

The plan from the start was to have the prop horizontal with the #1 Cylinder at TDC. It just so happen to require moving the prop in that particular direction and only one hole.
 
My Vibration Solved Also

I had the same problem as the OP. I have an IO-540 with the Hartzell HC-C2YR 2-blade. I normally cruise at 7000'-10,000', WOT, 2300rpm, LOP, 11.0-11.5 gph. and always had a slight 1/2 order vibration, (felt more like an oscillation) when I pulled the rpm back from climb rpm. I re-clocked the prop one hole CW as the OP described and now it is much smoother at cruise, (it was always ok at high power settings for take off and climb). Thanks again Storch for getting this info on the forum.
 
Barry,

Did you need the Lycoming bushing removal tool, and did your replace the bushings with new ones or reused the existing bushings? I'm planning to re-clock mine too this weekend. The accelerometer is still mounted in the cabin and I'll be able to get some in-flight spectrum data for comparison.

Lenny
 
Bushings

Hi Lenny. I was able to remove the bushings with a brass drift and a hammer, they came out easy. I spoke with a few engine guys and they said it was ok to reuse the bushings if the threads were ok and they had a good fit with the prop flange. I removed the 72060 from the index position and installed a 72074 bushing, which has the 0.78 dia and 0.78 height for the prop drive; I then traded a 72061 and 72062 positions so I had the 72061 one hole CW from the original index. I used a long 1/2'' bolt with spacers and nuts to install the bushings. I now have five drive bushings and one flush one, and the flywheel is still index properly. As a side note, when I checked out my original bushings, two of them were not seated all the way against the prop flange, so I pulled them in tight also; I guess I thought that the prop torquing would pull them in, but it did not. All in all not to bad of a job to do. Email or pm me if ya have any more questions
 
I just did this and it worked for me!

My friend Scott Schmidt sent me this link when he noticed it here. He knew I had tried a few things to make my RV10 run smoother. I initially dynamically balanced the prop. That didn't change it much and it was surprisingly well balanced to begin with. I then called Lord mounts and tried some different mounts on the diagonal that they suggested. That didn't seem to work either. So I left it as is and put up with the rumble. I have an IO-540-N1A5 which has a thicker crank and heavier counterweights. I thought it was just an engine/plane/prop combo that had a shake and that was that. I noticed after flying other RV10's that mine had a worse shake. Scott Schmidt's and Tim Olson's RV both felt smoother than mine. After Scott sent me this link I started doing some research. I read all the prior posts and then called Les at Hartzell. I left a message thinking he may not call back. He has left his prior position and is now working for Hartzell and the NTSB on accident investigations. He returned my call and we chatted for a bit. We decided the best plan of action was to re-clock the prop by changing out the bushings on the prop flange. I was going to rent the tool or make one but after looking at them I decided to make some spacers and use a bolt and nut combo to push out the bushings. The same tools worked to pull them back into place at the new location. My prop was set at #1 TDC pointing to 1 and 7 looking forward from inside the cockpit so I had to move the bushings one hole over to make the prop 9 and 3. I changed four bushing so the weight would be balanced on the flange. I finally finished my condition inspection and flew the plane. What a difference! I can easily tell this did the trick on mine. Before I changed this the rich setting on takeoff and climbout would be the worse for vibration. Mixture set to the rich side in cruise with the prop at 2400 was bad too. I would climb to cruise altitude and run LOP which would smooth out the plane a bit. Now all settings are smooth. Made a huge difference on my RV10.
 
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Re-clocking worked for me

Thanks to all who posted on the subject of prop vibration! Re clocking worked for me. The plane is smooth at all RPMs. Since my crankshaft had five drive bushings it was only necessary to move the shorter one one hole CCW to re-clock the prop since it is the short bushing that determines the position of a Hartzell prop. Note: All crankshaft holes are the same size for the bushings, there is one larger hole on the starter ring gear support (flywheel) that indexes it (its position is not changed). The prop's position is determined by the short bushing on a Hartzell prop.
 
I will add one additional RV-10 to the re-clocking success story.

After balancing my prop to .01 IPS, it still had a slight vibration I could feel in my seat. It has been there since day one 750 hours ago. After reading this thread I decided to try it myself. I ordered two new bushings from Air Power Inc., a 79024-S and a 72155-S for a total cost of $78. I have the D4A5 with the BA 2 blade prop. I clocked the prop to 9 and 3 o'clock with #1 at TDC. It again balanced out to .01 IPS @2400 RPM.

Night and day difference. That pesky vibration in the seat is gone.
 
didn't work for me.

I have the same D4A5 engine from Van's with the BA 2 blade prop, and had to get the same bushings 79024-S and 72155-S.
My half order vibrations in cruise doubled up after the reclock and rebalance. Went from .144 IPS to .281 IPS on the half order vibrations. It was real smooth at full power, but I couldn't stand the floor thumping at cruise (2360) rpm. I ended up clocking it back to original.

Bill, did you grab a spectral graph of your balance? I'm real curious why it didn't work out for me.
 
Lenny,
I did notice that the prop was the smoothest at higher RPMs. It is still smoother than it used to be at 2300 prior to reclocking it, but definitely the least amount of vibration is at 2600+. Overall, it is far better @9-3 then it was @7-1.
The Dynavibe I am using only captures 1st order acceleration, so I do not have the 1/2 order data.
 
Hello all,

I have a RV10 with IO-540D4A5, two bladed Hartzell HC-C2YR-1BFP/F8068D.... Standard stuff from Vans..

I have been trying to isolate vibration so this seems the next step for me. I commute most days for about an hour and it's starting to be a pet peeve so I want prepare to give reclocking the prop a try. After that, I'll get Vic to balance the prop.

Questions:
Only see reference to the "special tool" on the first post. How has everyone else dealt with not having the tool?

I see two spacers .... 79024-S and a 72155-S .... that looks like I need to have on hand as well.

Anything else that I need to have on hand other than an extra hand? Appreciate this information!
Doug
 
I ordered the bushings from air power. The Lycoming tool is not necessary, a box end wrench several long bolts and washers, and a socket is all that?s needed to fashion your own removal tool to remove and install the bushings. Looking at the prop from in front of the plane, the prop is clocked clockwise, counter to its rotation, so that the blades are at 9 and 3 o?clock when #1 is at tdc. The prop hub o ring should also be replaced.
 
I Have an IO540-D4A5 and HC-C2YR-1BFP/F8068D prop and have been chasing airframe vibration for a while. Finally after having tried prop balance, baffle replacement, engine mount replacement, ignition timing and checking all areas of the cowl for interference, I re-indexed the prop and the difference is day and night. It was a painless process done by CopaAir in Florida and took 3 hrs to complete. I did not have to buy any new prop flange bushings and borrow or rent tools to perform the work. If you are having airframe vibration, I highly recommend re-indexing after you have tried all other low hanging fruits. PM me if you need specific information.
 
I'm having issue with airframe vibration on my newly flying 10 with an Aero Sport 540 and the 375HRT WW prop. I dynamically balanced it from .6 down to .04 but still feel the vibrations while flying at all RPMs. Seems reclocking is another trick to try, as a few folks have recommended it. I don't have to move bushing or anything, but how do folks determine how much to reclock? For reference, I had to add 60 grams to balance the prop. When the engine stops, the same blade is always at 6 oclock, putting the weights at 12 oclock. Should I reclock it by a certain rotation? 45* or 90*?
 
I'm having issue with airframe vibration on my newly flying 10 with an Aero Sport 540 and the 375HRT WW prop. I dynamically balanced it from .6 down to .04 but still feel the vibrations while flying at all RPMs. Seems reclocking is another trick to try, as a few folks have recommended it. I don't have to move bushing or anything, but how do folks determine how much to reclock? For reference, I had to add 60 grams to balance the prop. When the engine stops, the same blade is always at 6 oclock, putting the weights at 12 oclock. Should I reclock it by a certain rotation? 45* or 90*?

I rechecked men one bushing clockwise as others had indicated on this subject. You will have to move the index bushing. Don't overthink this.
 
I'm having issue with airframe vibration on my newly flying 10 with an Aero Sport 540 and the 375HRT WW prop. I dynamically balanced it from .6 down to .04 but still feel the vibrations while flying at all RPMs. Seems reclocking is another trick to try, as a few folks have recommended it. I don't have to move bushing or anything, but how do folks determine how much to reclock? For reference, I had to add 60 grams to balance the prop. When the engine stops, the same blade is always at 6 oclock, putting the weights at 12 oclock. Should I reclock it by a certain rotation? 45* or 90*?

You follow the hartzell recommendation. I can send you the hartzell doc that tells you where/how to reposition the lugs. Send me an email request and I will reply with the doc. I did mine during the engine overhaul.

EDIT: sorry, just realized you don't have a hartzell. However, the same clocking approach would probably work. I would be a bit concerned though as yours is a much lighter prop and may not respond the same way. I have not read of anyone doing this with a WW, so be carefull in following this recommendation.

Larry
 
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Another thing to be aware of.

A 2 1/4 extension is solid , not a spool. This requires the prop bolt holes to be 30* off from the crank flange holes. Unless the prop is correctly drilled to be compatible with this, you CANNOT align the prop horizontal (colinear) with the crank journal at TDC. My 0320 is totally balanced on engine parts and prop dynamically balanced. It is way better than a Cessna, but not turbine smooth.
 
Hartzell not balanced from new

Hi Tim and others with prop vibration,

For over 4 years I lived with a vibration that I came to accept as normal in my RV-10. I had the prop Dynamically balanced 3 times and tried to convince myself it was somehow a little better.

It was not until a persistent front crank seal oil leak convinced me to remove the prop and take it to Suncoast Aero Engines Prop shop here in Australia to have a look at it while I was replacing the crank seal.

0-3UnLEcCSK8vukr5WA-P7G4Ooif-6SfX5iHHFIVzUuCDWiiDZRrf2_ZRJeYxu4I3mETjmvz_g6-UlBvuhh3AaWR9VLhsaYa2qDMCwrZ1qL6ZY8wXLkCFtr51Due7f5kmpGVcWF7gfECvKM1aVvy9RN7kr-gkbP4nxFy0QR3a675fMST36QwP6I_YLDDUOFAZNAhQphu7bS5uuuBekDpF6t7znC-9F7GoCzHECUzn4m6fcvJHqrlkYGJFPfVCu5GKRLhmlYztHDVehfIsTGNf5fdpD_aQh0FMJD4ow9IQjoZ11nqFvXiE7pH-7O-sD5x76V7ThS6pQTgQpeqJPG7erkAai3WaL85ln5SxTPeJBvceQqOtnZC3B7nEqCocAtObfDaE1hbbwgBnm1SYeG0i1Bsrjon9KTt02cFFuJPPMBXdg3mZIohoU86jDbuzLjh_uMC560emnT-jwqGJSvwMBiH7eX3_cFoK_X2NtujerNOMR2Y5Bu9llOOpEhmnrk96_m9oiXIq-Bc6Esa0y6UNROfV9LKJaRDS8bE_EMZefSCNgfENBLRoypY4lR2bJ8CHBcpff3IhzXXYTMEKZEQaec28xszO0dknAk3fiitX4pcwtbV45B748vVYohsRGFJI4JFRndg8ulLlP4uZVZ4n2_De75HhABjyzdpgee38OBxxIKwWUPKh_EFsiokwADbxDCyPHgX16ccsOtKBxD-_cGoeo1tgjaefyWDeDxePjdZwrLJ=w499-h664-no


I visited the shop while the work was been done and was surprised that my prop was over 40 grams out of static balance and the technician was as surprised as I was ! He commented that it was rare to find a hub that was so far out of balance. It required weights to be added on both axis to get it right.
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So going back on the aircraft I also re-clocked as per the instructions listed here and have finally be rewarded will the smoothest ride I have had in my '10.
The highly accurate vibration analyser I have in my aircraft ( sunvisors )are now dead still in cruise instead of the continual flutter I had been used to.
I also Dynamically balanced the prop and engine combo again and it balanced easily.

Very disappointed to find out that it was my new "balanced" Hartzell that was the problem all along but very happy to close this chapter on my RV-10 and call it DONE !
 
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Hartzell our of balance

I just went through this as well. Your photos look exactly like my case. For years I flew with a vibration, it was there from first start on. I had it balanced and was told it was almost perfect... still had a vibration. Finally, like you, we had the prop balanced and required a serious amount of weight to get it right . the plane is so much more smooth now.
 
The previous few posts seem to indicate that somehow a static imbalance was not being detected during dynamic balancing. That doesn?t make any sense to me; I?ve always been led to believe that a dynamic balance replaces and is superior to a static balance. Anybody care to correct this and explain?

Regards
Erich
 
So after the static balance do you dynamically balance it? I would think you would have to to make up for imbalance in the spinner and backplates.
 
Hello Erich,

I was also confused as to why the dynamic balance only made minor changes to my vibration .
My thoughts are that the weights were added in both fore/aft hub location and blade location so maybe if I had access to a better prop balancer like the Dyno Vibe pro, I would seen the half order vibration recorded.

(My prop was balanced with backing plates and spinner fitted)

This is an extract from my report,

Suncoast Aero-Props
?Also for your information, Your blades are tracking exceptionally well (1/64?) and the blade angles were spot-on with 13.5? for the low pitch and 30.7? for the high with no variation between the two blades, so there?s no issues there.
The balance weights I added equate to about 50grams of weight, so hopefully after re-clocking the prop 180 and another dynamic balance your vibration should be remedied?.

I would definitely be checking static balance if you have already done a Dynamic balance with no improvement.
 
Why static not being picked up in dynamic

My guess, last person to do mine knew what he was doing (30 years in dynamic balancing of helo blades) and possibly the one prior to that didn?t. I don?t think it was any more than that. It wasn?t statically balanced after I added a spinner and other parts Hartzell didn?t include initially; it was dynamically not corrected and I thought it was, based on feedback, now it?s done correctly and it?s right.
You are correct dynamically it should pickup an unbalanced static.
 
My guess, last person to do mine knew what he was doing (30 years in dynamic balancing of helo blades) and possibly the one prior to that didn’t. I don’t think it was any more than that. It wasn’t statically balanced after I added a spinner and other parts Hartzell didn’t include initially; it was dynamically not corrected and I thought it was, based on feedback, now it’s done correctly and it’s right.
You are correct dynamically it should pickup an unbalanced static.

To add to the above I think the equipment used to balance may have something to do with it as well. In my experience with tools, test equipment (and most things in life), you get what you pay for. The vib sensor alone that I use with my MVib II balancer cost more than some entire vib kits. I've also seen folks post balance results that I know are practically impossible to obtain. In 15 yrs of balancing hundreds of airplanes I've never been able to achieve 0 IPS.
 
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