SB 14-01-31; RV-6, 7, 8

[tracy]

I wonder what the relation would be to those who are operating at gross weight a lot of the time? If the heavier weights are an issue, could the GW be reduced to do away with SB.

[Mark Burns]

Originally Posted by Rotorheadrob

RV-8A
O-360 A1A
Hartzel CS
Finished 1999
+1100 hrs
Multiple Owners
Yes-Acro
Yes-grass
Yes-dirt
Yes-pavement
Yes-VFR
Yes-IFR
Yes-Formation Flying
Yes-long X-C trips
Yes-Hot Wx ops
Yes-Cold Wx ops

No Cracks. 😎👍🍺

Notches??
I'm guessing "No"

Mark

[GaryK]

RV7A
2005
1135 hours
O 360
Hartzell BA CS Prop
95% pavement
Relief notches in all 4 corners
No cracks on either SB.

Gary
N715AB

[lostpilot28]

Originally Posted by Neal@F14

I checked all 4 corners...

Two of my corners were blatantly obvious that there's no sign of even the remotest possibility of a crack, but two corners (upper starboard and lower port) had enough paint on them that I couldn't be absolutely certain... so I spent the time with a box of q-tips and various solvents to remove the paint and in the end there were no cracks to be found. I discovered that fully-cured, ten-year-old polyurethane paint and epoxy primer is awfully tough to remove with typical hardware store solvents... a mixture of non-chlorinated brake cleaner and MEK worked better than any other solvent alone, and it still took a long time and a lot of rubbing with q-tips. I wasn't about to use any harsh chemical paint stripper for fear of inducing corrosion.

Thanks, Neal. I ended up using a lot of Q-tips and some lacquer thinner. Most of my empennage was primed with rattle-can primer, so it came off pretty easily.

I think my motive for asking the question about upper vs. lower cracks would be to see if anyone is seeing cracks on the bottom corners. Seems like the upper corners are getting all the attention...

[Terry Lutz]

RV-8
s/n 80462
200 TT
Completed 6/06
O-360-A1D
WW200RV - balanced
some grass
some acro
towbar
no notches
no cracks

[Mark Burns]

When I removed the top angle I was surprised to see fretting.
See photos below. The metal was flexing a good bit to cause this.
Its not deep and can be cleaned up with Scotch Brite.
I checked the botttom, both sides with dye penetrant and no cracks on the bottom.
In the photo the elevator is turned upside down.

I've cut two of the spar flanges back at an angle so far.
Surprisingly, this may be the most difficult part of the SB.

Mark

[bret]

I finished taking mine apart this morning, if you really look at it, this mod is going to add a great deal of strength to the forward spar. I can see where the flimsy sheet metal spar could flex easily during non SAL flight, stalls, spins ect.

[bret]

I wanted a little more room so this is how I did mine.

[floridawing]

Thank you for the pictures and post! It is very much appreciated!

[gerrychuck]

Originally Posted by jrm7997

I was just thinking about this very topic. What should you use to remove the corrosion resistant materials or paint to be able to do this inspection?

I've heard of using MEk but also biodegradable paint removers or aircraft type paint removers.

Not trying to hijack this thread but maybe make it part of it???????

Or is there another thread asking this question?

Thanks

I did my initial inspection yesterday, but had a tiny niggling doubt about one corner. Went back today with a can of lacquer thinner from Canadian Tire (MEK and toluene). Cleaned the 10 year old overspray and primer very easily; only had to use 2 Q-tips to get down to shiny metal around the notch. Glad I did; my hi-res photos after cleaning leave no doubt that there is no crack, and the cleaning process only took me about 5 minutes.