Sheared Rivits in both Main Gear Boxes

[GAHorn]

Cessna's manual refers to replacement of Hi-Shear rivets with AN bolts...not common AN420's, etc..

An excellent example of such an approved replacement can be found on the wing-strut attachments to their end-forgings. (In fact, Cessna did just that in about 12 newly-mfr'd airplanes in late '52 while they had rivets on back-order. Ultimately they abandoned Hi-shears and went with 420's.)

BUT.... anytime threaded fasteners are used to replace rivets... one should consider that only reamed-holes will equally share the load with bolts (which should be close-tolerance bolts in the case mentioned by Tom.) Otherwise, only one bolt in a set might be carrying the entire load.

[T. C. Downey]

If you are going to all the trouble of reaming and setting bolts, you will be better served by these
http://www.peerlessaerospace.com/Produc ... ISULOK.pdf

[48RagwingPilot]

FWIW, when I converted my '56 C182 to C182TW in 2011, had to install new inboard and outboard gear boxes as well as a new floor above the landing gear bulkheads and a new belly skin below. The only way to gain access to drive the rivets was to detach and roll up the entire floor forward of the rear door post. Somewhat time consuming but makes access possible. Even then I had to use AN bolts and cherrymax rivets in several instances due to lingering access issues. The Seattle FSDO had no issues with either.

[T. C. Downey]

Even then I had to use AN bolts and cherrymax rivets in several instances due to lingering access issues. The Seattle FSDO had no issues with either.

They shouldn't,, the structural repair manual supports the usage of both.

[mschwab]

Dear George, Bruce and Gang;

Thank you for the very valuable information and time you have spent on me and my airplane problems. I immensely appreciate, George and Bruce, all the time, effort and stress you spend on this group! I also appreciate all the members that so graciously give help also. And a very special thanks to blueldr for the special tutelage!!! I'm a bad typist and worse speller and I need a blueldr to keep me hopping in the right direction (ribbit-ribbit). I feel kinship to you blueldr and know you will have my back!!! I really would like to know you better! Could you teach me how to do spell check on this site...plz). I will try to digest all this information and make the right dicision. I will continue to watch all my posts in case any new info shows up. Thank every one for the help and I'm so thankful for you guys.

Yours truly

Mike

[blueldr]

Sorry, but my spell check is my daughter, Nancy, who says she hasn't misspelled a word since the third grade. I just email her in HongKong where she is a pilot for FedEx and has been flying the Asian routes for about eighteen years now.

[mschwab]

Thank you one and all for the wealth of information and ideas for my difficult and perplexing problem. Now I have to make the right decision George and Bruce...I appreciate so much all the time and stress you spend on The Hanger. Money could not buy the experience and wisdom of the fine people that are so kind helpful! And to blueldr...a special thankyou for your tutelage! I am a bad typist and worse speller.....BUT....I am very assured that the blueldr has my back and will keep me hopping in the right direction (ribbit-ribbit)! :^D I will not tackle this job immediately so if any other ideas please let me know. Thank you.

Sincerely
mike

[blueldr]

Rivits, rivets, ribbits , ribbitt, --- what the hell. Good luck on the repair, Mike. If you need any duck tape, I have some.

[GAHorn]

Rivits, rivets, ribbits , ribbitt, --- what the hell. Good luck on the repair, Mike. If you need any duck tape, I have some.

Waddle he need duck tape for?

[blueldr]

Among my contemporaries, duck tape is used, rather than new through bolts, on a MAJOR overhaul.

[mschwab]

thanks on the tip for close tolerance bolts. Since it appears I can replace sheer rivets with close tolerance bolts and not the regular rivets I will proceed with that. Any tips or pearls on removing these large rivets??

to me

---------- Forwarded message ----------
From: Jeff Meyers
Date: Wed, Jun 19, 2013 at 8:58 AM
Subject: Re: Rivets and Bolts
To: Michael Schwab

I believe you will have a hard time finding equivalency charts for replacing rivets with bolts. This is due to the rivet being used for shear applications and clearance fit bolts are not recommended for this.

But I'm sure a solution exists depending on the application (primary structure, brackets, etc.) and the access available. Find out the application and access for these holes, because a blind rivet might be a solution.

Jeff

On Tue, Jun 18, 2013 at 10:59 PM, Michael Schwab wrote:

Hey Jeff,

My dad was working on his plane and was looking for charts that show equivalent sized aviation grade nuts and bolts to use to replace rivets that are gone since the rivets are in a spot nearly impossible to replace with rivets. Do you know of any such charts or where they might be found?

Michael

[Aussie_1]

Guys

Just done an annual on my C170 and found the same problem, or at least the LAME did. Repair required removing both gear legs, drilling out the sheared rivets and replacing with structural screws. Seven rivets, three on one side and four on the other required replacing. About a $1,000 repair job.
Finding the problem was a bit of luck in the first place, an inspection through the floor access inspection panel revealed a single stray rivet head much searching required to locate the source.

The concerning issue is what caused the problem. OK there has been a couple of "arrivals' and I normally operate of a grass strip but nothing that I would expect to cause this sort of damage.

I guess the moral of the story is always take a look in those hard to get at places every so often.