Van's RV-8 and SV32 Pitch servo installation hardware not runs (Safety Issue)

[lucaperazzolli]

I tried to install a brand new SV32 pitch servo into an RV-8, pre 2006 - not prepunched.
I strictly followed all the Dynon product Information respecting the drawing but I jumped into a NO-GO situation.
The elevator bellcrank bearing rivets are not cleared with the retention bolt of the servo as per Dynon plans.
I tried all the possible standard creative work like changed the washer into an L, removing the star lock washer but nothing satisfy me in a safe manner.
One solution could be changing the AN470 rivets to AN426 but I think that clearance here is a big factor, or found a different bolt ?
Advice needed, please.

Luke

 

[jakej]

Hi Luke,
A side on picture & info where the fwd elevator pushrod attaches would be helpful ?
Maybe the mounting brackets for the elevator bell crank has been cut down in the area where the servo mounts ?
That bolt you are asking about will not work in that position, from what I see the tech drawing shows a different profile for the mount brackets & the servo attach bolts will need to be on the other side of the bellcrank pivot. Just a guess here

 

[RV8JD]

This issue has come up on the VAF forums. Check out these threads, they may help:

Dynon A/P pitch servo mounting?

I am working on installing the Dynon A/P pitch servo in my RV-8 QB fuselage. As you can see in the attached image, there is interference between the head of the forward servo mount bolt, just behind the bell crank pivot bolt, and the rivets in the elevator bellcrank. It seems like this would...

vansairforce.net

Dynon Pitch Servo Installation RV-8

Hey Guys! Some questions to the Dynon Pitch Servo Installation: - How to fix the Dynon Pitch Brackets at the fuselage? Would you prefer rivets, screws or don?t fix them anyway? - Did you trim the stringers in the middle section or isn?t it more clever to trim the overdesigned pitch brackets...

vansairforce.net

 

[lucaperazzolli]

Hi Luke,
A side on picture & info where the fwd elevator pushrod attaches would be helpful ?
Maybe the mounting brackets for the elevator bell crank has been cut down in the area where the servo mounts ?
That bolt you are asking about will not work in that position, from what I see the tech drawing shows a different profile for the mount brackets & the servo attach bolts will need to be on the other side of the bellcrank pivot. Just a guess here

Thank you Jake for your answer - The brackets for the bell crank are the original kit sold by Dynon (DYNON AUTOPILOT PITCH MOUNTING KIT FOR RV 4 / 8 pn: 101020-002), no cut done. The tech drawing is mirrored respect my photo that is taken from FWD to AFT of the aircraft.

 

[lucaperazzolli]

This issue has come up on the VAF forums. Check out these threads, they may help:

Dynon A/P pitch servo mounting?

I am working on installing the Dynon A/P pitch servo in my RV-8 QB fuselage. As you can see in the attached image, there is interference between the head of the forward servo mount bolt, just behind the bell crank pivot bolt, and the rivets in the elevator bellcrank. It seems like this would...

vansairforce.net

Dynon Pitch Servo Installation RV-8

Hey Guys! Some questions to the Dynon Pitch Servo Installation: - How to fix the Dynon Pitch Brackets at the fuselage? Would you prefer rivets, screws or don?t fix them anyway? - Did you trim the stringers in the middle section or isn?t it more clever to trim the overdesigned pitch brackets...

vansairforce.net

Thank you for your interest in my post - It's seems a common problem [ you are a better VAF searcher than me ].

I asked Van's and they say not to change the original AN470 rivets (despite 0.063 thickness of the bell crank), anyway there are only 2 or 3 to change only ...

For sure it's a nice idea to use the fwd top empty hole of the SV32 to install another drilled head bolt to wire safety the 'killer' one at bottom.

I'm fighting with really small clearance, brainstorm ON !

I really don't understand why Dynon did not fabricate the bracket a little bit longer to clear this bolt that is really a factor.

Luke