SB 18-02-02 Potential cracking in the horizontal stabilator front spar

[Tony_T]

My take would be that by scuffing the SS washers and alum brackets and glueing them together the SS at the interface would stay in the active state. Especially if the assembly is primed. It looks like the aluminum would still be slightly sacrificial but for a corrosion cell to form there would have to be an electrolyte present.
Anxious to see where this thread goes...

[Piper J3]

Originally Posted by Tony_T

It looks like the aluminum would still be slightly sacrificial but for a corrosion cell to form there would have to be an electrolyte present.

Tony, you live by the ocean, so salt air with lots of rain in the PNW would be a consideration...

[Tony_T]

Originally Posted by Piper J3

Tony, you live by the ocean, so salt air with lots of rain in the PNW would be a consideration...

What rain?

[RFSchaller]

Seems like steel and aluminum are in contact at many points in an aircraft. I’ve never heard of it being a problem. Has anyone else?

[rv9builder]

Hi Rich,

Yes, I’ve heard of it being a problem with some PA-28s. Here’s a very sad news story and a video that shows how badly aluminum and steel corrosion can be.

https://www.avweb.com/avwebflash/new...-230590-1.html

https://www.youtube.com/watch?v=-D5vCoWKgII

[pilotyoung]

All of the posts and pictures are very helpful. I have not started mine yet. I am wondering how many owners have actually found cracks after doing the inspection?

Thanks.

[rv9builder]

Originally Posted by JwWright57

I hear you Tony! I had to re-rivet one of the anti-servo hinges and ended up with the rivet tails inside the stabilitor. I cleared them out with a magnet on a long stick and a LOT of fishing around. It was a real PIA.

Has anyone found an easy way to remove the rivet stems after drilling out the rivets for the service bulletin? Amazon.com has several magnetic pickup tools that look like they might be helpful. Has anyone tried one?

Thanks,

[ben barron]

while one of us rotated the HS around the other caught the moving remnants... took 5 minutes...not a big deal

[Jim T]

I installed the stabilator fiberglass tips at the same time. With the end ribs removed I tipped the H.S. on to the leading edge so the rivets went to the front and then up on end and out the rivets fell out.

[rv9builder]

Thanks, Ben and Jim. I appreciate your suggestions!