Frustrated - Surfaces Won't Balance

[LevelWing]

About 18 months ago we embarked on a journey to paint the plane (C Model). We did all the prep work ourselves to include the sanding and stripping of the control surfaces. Our friend painted it (he's experienced in aircraft painting) and it turned out beautifully. Except the control surfaces wouldn't balance. More specifically, the elevators and rudder won't balance. The ailerons were no issue and are back on the plane. We re-stripped the control surfaces thinking maybe there was too much paint on them. As it turns out, even stripped, the surfaces won't balance. I've contacted numerous people for help and there doesn't seem to be much luck. I'm now asking the MooneySpace community for their advice/opinions on what should be done. N201MKTurbo has been very helpful during this process, it's just unfortunate nothing has worked thus far.

We need to add weight to the elevators/rudder but Mooney apparently doesn't make the parts anymore and suggested we find a salvage/junk yard for the parts. We're currently in the process of doing that, but it would seem others should have it. My mechanic has contacted the big shops, including Lasar and Beegles along with Mooney itself. I'll post the part numbers in the event anyone has a lead on them here. Some of you may remember me asking for a particular Mooney manual a while back, which is directly related to this. The J model manual will tell you to add weights where necessary but the C model manual will not.

1ea. P/N 460011 Rudder balance weight. Mounts with 4 rivets. Minimum actual weight of 3.55 lbs. (56.8 oz.)

2ea. P/N 460011 Elevator balance weights. Mounts with 3 rivets. Minimum actual weight of 3.50 lbs (56.0 oz.)

I appreciate any advice/guidance you all can provide.

[thinwing]

Owner produced if not available from Mooney...what are they made of?if they are riveted in place ,prob not lead are they simple steel stamping?plates?Maybe an Email Stacy Ellis at Mooney could give some ideas

[LevelWing]

I've contacted both Stacy Ellis and one of the engineers at Mooney, as has my mechanic, and they don't make the parts anymore. 

[thinwing]

Ok..than its owner produced...I also assume once you stripped the rudder and still couldn't balance this condition is not new.Can you detect a water or debris inside from prior stripping?

[Alain B]

Just now, thinwing said:

Ok..than its owner produced...I also assume once you stripped the rudder and still couldn't balance this condition is not new.Can you detect a water or debris inside from prior stripping?

Maybe you can get a copy of the enginering drawing , and get them made in another machine shop . 

[LevelWing]

5 minutes ago, thinwing said:

Ok..than its owner produced...I also assume once you stripped the rudder and still couldn't balance this condition is not new.Can you detect a water or debris inside from prior stripping?

Is there anything in writing that says I can use something owner produced? My mechanic can make what he needs but he wants something in writing stating that it's legal. I believe that's the biggest hold up I have in all of this; having something to reassure the mechanic that it's legal and safe.

[ArtVandelay]

Is there anything in writing that says I can use something owner produced? My mechanic can make what he needs but he wants something in writing stating that it's legal. I believe that's the biggest hold up I have in all of this; having something to reassure the mechanic that it's legal and safe.

Its in the regulations, Mike Busch has a video on this topic. Take one of the weights down to you local fabricator, and tell them you need copies of this piece. You dont have to fabricate it yourself but you do have to insure it's fabricated to same dimensions, material, ie you are ultimately responsible for the part, and you AP has to be confident as well.

[LevelWing]

10 minutes ago, teejayevans said:

Its in the regulations, Mike Busch has a video on this topic. Take one of the weights down to you local fabricator, and tell them you need copies of this piece. You dont have to fabricate it yourself but you do have to insure it's fabricated to same dimensions, material, ie you are ultimately responsible for the part, and you AP has to be confident as well.

Through Google, I've found the following (I assume this is what you're talking about):

https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC 20-62E.pdf

http://aviation.stackexchange.com/questions/8409/how-are-owner-produced-parts-handled-under-faa-regulations

http://www.ecfr.gov/cgi-bin/retrieveECFR?gp=&n=pt14.1.21&r=PART&ty=HTML#se14.1.21_19

http://www.eaavideo.org/video.aspx?v=1105297993001

I've been taking the wrong approach to this it would appear. I've been looking for a way to find the parts to purchase, not producing my own. 

[tony]

I think this is what you need.  21.9(a)(5)

Sec. 21.9
[Replacement and modification articles.]

[(a) If a person knows, or should know, that a replacement or modification article is reasonably likely to be installed on a type-certificated product, the person may not produce that article unless it is--
(1) Produced under a type certificate;
(2) Produced under an FAA production approval;
(3) A standard part (such as a nut or bolt) manufactured in compliance with a government or established industry specification;
(4) A commercial part as defined in Sec. 21.1 of this part;
(5) Produced by an owner or operator for maintaining or altering that owner or operator's product; or
(6) Fabricated by an appropriately rated certificate holder with a quality system, and consumed in the repair or alteration of a product or article in accordance with part 43 of this chapter.
(b) Except as provided in paragraphs (a)(1) and (a)(2) of this section, a person who produces a replacement or modification article for sale may not represent that part as suitable for installation on a type-certificated product.
(c) Except as provided in paragraphs (a)(1) and (a)(2) of this section, a person may not sell or represent an article as suitable for installation on an aircraft type-certificated under Sec. Sec. 21.25(a)(2) or 21.27 unless that article--
(1) Was declared surplus by the U.S. Armed Forces, and
(2) Was intended for use on that aircraft model by the U.S. Armed Forces.]

[LevelWing]

Thanks. By reading that and everything else I've found, it would appear that the parts I need fall into the allowed category. My mechanic has the ability to make the parts, but this is probably what he needed to do it and feel confident legally.

[thinwing]

Correct..next you either need an example or a factory drawing and specification of materials used..I am surprised the factory can't help you more..for the rudder and elevator ,except for the extension piece on the long bodies ,why isn't a balance weight built for a new Acclaim not very similar?

[LevelWing]

My mechanic was provided the specs by Mooney which includes the minimum/maximum weights. It's not a drawing but it does specify exactly what the weights must be for them to be allowed. If that's what you're referring to then I think we're set.

[thinwing]

No Drawing so how do plan to define the shape and dimensions.?

[LevelWing]

2 minutes ago, thinwing said:

No Drawing so how do plan to define the shape and dimensions.?

I'm not sure. I don't know if he already has that information or not. If not then he'll probably reach back out to Mooney for the designs if they still have them. Is there a reason he can't determine what it needs to be on his own if that information isn't available?

[ArtVandelay]

23 minutes ago, thinwing said:

No Drawing so how do plan to define the shape and dimensions.?

I assume there is already weights on it that can be used as templates?

[jetdriven]

It's made of cast lead. You should be able to make a mold and then finish it with a file. 

[thinwing]

Anybody on MS static balanced a control surface before?

[MB65E]

13 minutes ago, thinwing said:

Anybody on MS static balanced a control surface before?

Yes. Several times. Ailerons were harder for me. Just be sure you have the most current manual and you are looking at the right S/n per your airplane. It's changed a few times, and there are several different sets of flight controls and Data points. Mine are all "in" but don't breath on them while balancing them. My ailerons were really close. I refinished them trailing edge up to allow for the paint to dry fwd. I was also told by some others to sand the clear off the bottom...

Its kinda black magic. I'd venture to guess over 50% of our airplanes don't meet the book spec with paint on them. There will not be a real answer other than re-making the weights... But "why it's heavy now without 6 layers of paint???" I know...

strange!

-Matt

 

 

[takair]

Just to confirm, your mechanic is using the allowable static UNbalance force?  Unlike balancing a wheel or a propeller, this means that the surface will not be truly balanced, but may actually still be trailing edge heavy.  This is measured at the unbalance point provided in the mm.  On some aircraft you would need so much weight that it would create other issues.  If you don't take this unbalance force into account, it can be a frustrating experience.  The balance is that required to prevent flutter and is calculated and test flown by the manufacturer.  

[cliffy]

Lets start at the beginning -

You are sure you are following the MM by model AND serial number for your surfaces?

What condition are you balancing in - 

        Correct orientation, correct side up?

        With or without the steel bellcrank arm on?

       Are there any "repairs" to the surfaces? Patches? Non factory skin laps? Any repairs ever to the surfaces?

       Any Bondo on the surfaces? 

      What figures are you working with for the math?     Arm length to where the scale is pressed, weight on the scale?

      Pictures of your set up would help    Not trying to knock who ever is doing it but maybe something is being missed or done wrong 

Let's try an go over everything before you go wild on making parts . It balanced at one time even if it was when it left the factory.

 

[MooneyMitch]

I just went through this process last week with my rudder balancing during the paint process.  Rudder was over top limit before and after stripping.

After much deliberation and consultation, mechanic simply removed top rudder cap, calculated needed additional weight and molded a new lead piece to top cap piece and installed the new lead piece up against forward end of existing lead rudder weight and reinstalled top cap.  New paint installed and we're good.  My newly painted vertical stabilizer is shown in my site photo.  Hope this helps you.  

Incidentally, a '64 E model is in the paint shop at this very moment with the same issue................rudder out of balance as removed from aircraft prior to paint stripping process.

[RobertGary1]

3 hours ago, LevelWing said:

I'm not sure. I don't know if he already has that information or not. If not then he'll probably reach back out to Mooney for the designs if they still have them. Is there a reason he can't determine what it needs to be on his own if that information isn't available?

My understanding is that if Mooney provided the drawings and your A&P makes the parts it's not an owner produced part, your a&p is now a producer and would need a PMA certification. I think owner produced means you need to drive this.

 

-Robert

[DonMuncy]

16 minutes ago, RobertGary1 said:

My understanding is that if Mooney provided the drawings and your A&P makes the parts it's not an owner produced part, your a&p is now a producer and would need a PMA certification. I think owner produced means you need to drive this.

 

-Robert

No. My understanding is, anyone can make owner produced parts as long as the owner is involved in the process. Telling the person making it, how, what materials, etc.

[cliffy]

The A&P can't just make a part from drawings. The owner HAS to be part of the process telling how to make it. or design it, or some other participatory process. Then it qualifies as Owner Produced. There should be written records showing the process. Lots of information on the net about OPPs  and how to do it correctly. There are several steps to qualify and you must meet ALL of them for the part to qualify. 

[thinwing]

20 minutes ago, DonMuncy said:

No. My understanding is, anyone can make owner produced parts as long as the owner is involved in the process. Telling the person making it, how, what materials, etc.

That's the way I see it also   A simple make me balance weight grog!should do it but the reason I brought up the balancing procedure itself was that Any a and p that didn't. Know owners could produce their own parts made suspect his ability