Question: 7 rudder bottom

[bret]

I hope I did not just waste 20+ Hrs. blending my rudder tips, But...for those who have done there rigging did the rudder bottom line up with with the fuse? I have a 2010 emp. kit and the bottom rudder glass had a scrib line on it where to trim. I thought I read somewhere, wait to put the bottom on till you rig with the fuse....but you know how it is.

[LifeofReiley]

Nope... You're good to go, will line up just fine.

[bret]

Phew! I was super scared there for a min. Thanks. For those that blended you know what I mean. I guess I will go start sanding the VS.

[SeanB]

Bret,

One thing I've heard from other builders is interference between the bottom rudder fairing (forward portion) and tailgear. I'm not there yet so can't confirm.

[LifeofReiley]

Originally Posted by SeanB

Bret,

One thing I've heard from other builders is interference between the bottom rudder fairing (forward portion) and tailgear. I'm not there yet so can't confirm.

Yeah... I think that was when the scribe line came into play at Van's.

[bruceh]

I just did this work on my 9 this week. The scribe lines are not even close. I ended up carefully measuring from the trailing edge of the rudder and made some preliminary cuts for the control horns. Once I was able to slide the cap up and in place, it was clear that the cap was much too low. I ended up cutting off quite a bit along the top edge from the forward end, gradually tapered up to the trailing edge to raise the cap up to match the level of the end bulkhead. Probably about 3/4". I also had to tweak one side more than the other, since the cap was not symmetrical. Looking at it head on, it was more of a J than a U shape. Here is a picture after working on this for several hours.



I still have to figure out the wiring into this, and don't forget to drill a 1/4" drain hole in the lowest point. I also ended up putting another hole for a fastener just aft of the control arms, since the cap was splayed out a bit there. There will be 10 screws on each side holding this in place.

The trailing edge of the rudder is very thin, and the cap's trailing edge is quite thick. I'm not sure if it is worth trying to get the last 2 inches of the cap flush with the rudder skins.

[LifeofReiley]

Hi Bruce,

What vintage is your tail kit if I may ask?

[JoeBlank]

Bret,

Definitely wait until you are fitting the empennage and rudder to the fuselage for the first time to make this final fit. Depending on if it is a tailwheel or nosewheel variant, the fit will be different.

Obviously the rudder bottom needs to have appropriate clearance with the tailspring on the RV-3/4/6/7/8/9 models. This is really the first time that the fit there becomes apparent. You may already have your wiring run by then so you can add that task/decison making into the mix.

On the 'A' models you really only need to worry about the fiberglass clearing the aft bottom skin and creating a nice transition off of that skin and onto the rudder bottom. Again, you won't know how that looks until the empennage is installed.

Just add that task to your Empennage Fit list and charge on into the next phase of the build...

[Larco]

If it is a tail dragger, I highly recommend waiting until the rudder is mounted on the vertical before final trimming of the bottom is done. I've done several these and on the tail dragger 7 or 9 some extra trimming was necessary. The front of the bottom interfered with the tail wheel spring. Larry

[LifeofReiley]

At at a 2011 tail kit, scribe marks are gone... no longer there. We've done a few Late tail kits with scribe lines with no fit issues. Maybe something has changed... I would think Joe would know.