Pitch Servo bracket on new RV-8 Kits

[rvg8tor]

The new matched hole kits have the elevator bell crank mount formed into the baggage floor ribs, they are not riveted on separately. The Dynon bracket is designed to replace the Van's bracket that gets riveted to the baggage floor ribs. You will have to do some work to get the brackets to fit with the new kits. I promised Dynon that I would post what I came up with to make the brackets fit. I will try to attach a PDF file that contains the 3 entries from my log, if you can't open it just go to my log site and the Dynon Pitch Servo has a separate category. It worked out really well even though it took some work to get it to fit. Maybe Dynon will be able to manufacture the brackets so they fit right out of the box.


Cheers
Mike
www.mykitlog.com/rvg8tor

 

[TexasRV8]

Thanks for the "new" -8 servo attach braket post.  I was going to ask the same thing.  You Log report is excellent.  It really helped me from reinventing the wheel.  Nice job.  Thanks again for the post.

 

[coyote]

I am installing the pitch servo on a pre-punched fuse. I am using a slightly different mount. Still placing it behind the bellcrank but on an aluminum angle "shelf" between the lower longerons. I have the 2.25" al pushrod from the instillation kit but need a 3.25" instead.(still using the same pushrod attach point on the bellcrank. Could I get a 3.25 pushrod from dynon?

 

[dynonsupport]

We don't sell pushrods individually or in custom sizes outside of the kits. However, here are the specs:

We use 6063-T6 aluminum tubing (6061 would work fine, but the size we need for our rod ends is harder to source)

O.D. 0.375”  (3/8”)  fairly common.  The 8 foot length costs around $6 from McMaster Carr.

I.D.  Can be anything LESS than .213”  (a solid bar would be fine as well). The reasoning for the .213” is:  A) minimum wall thickness for tubing strength.  B) That happens to be the drill diameter required for a ¼-28 tap.

Both ends need to be tapped for the spherical rod end bearings: we use ¼-28 threads for ours.  It could be whatever you need it to be for different rod end bearings though.

We drill the ends of each tube to .213” I.D. at a depth of 1” then tap.

 

[shersha]

I installed a home-made bracket on the baggage floor ribs which are now part of the elevator bellcrank bracket on the pre-punched RV-8 kit. My bracket holds the servo in front of the bellcrank on the same side (left) as the supplied bracket - which obviously doesn't fit the pre-punched fuselage kit. My push tube is exactly one inch longer than the original one and mounts to the bellcrank in the same hole drilled in the bellcrank. It makes it easier to safety the bolts and wire it since it is more accessible. If you have an aft battery (I don't), you'll have to mount it on a tray that locates it right of center, but in the same support location as called out in the plans.

 

[TomBurnett]

Thank you, Mike Elliot, for the info on mounting the RV8 pitch servo brackets. Worked great - and saved me figuring out how to cut apart the rib/bracket.