elevator pushrod problem

WingsOnWheels · #1 01-03-2015, 03:55 PM

I am rigging the elevator an ran into a problem. The forward (small) pushrod is contacting the top of the hole in f-605 before the elevator stops. I could make the hole slightly larger, but the rod is at a point it will hit the underside of the floor at the extremes of its travel. I double checked my measurements and the bellcrank and contol stick weldment, both are where they should be. I will call Vans tomorrow, but is this a common issue, or has someone else run into this problem?

RVDan · #2 01-03-2015, 04:16 PM

Make sure the belcrank aft of the baggage compt is positioned correctly. It should be vertical ( relative to the fuselage level ref.) when the elevator is neutral.

WingsOnWheels · #3 01-03-2015, 04:39 PM

Quote:

Originally Posted by RVDan

Make sure the belcrank aft of the baggage compt is positioned correctly. It should be vertical ( relative to the fuselage level ref.) when the elevator is neutral.

It is. The pushrod touches at both the forward and aft extremes, so i can't adjust it out.

AltonD · #4 01-03-2015, 05:12 PM

Don't know about the six, but on the 7, the sticks are not vertical with a neutral elevator. They are actually quite forward. Drawing shows maybe 30 degrees tilt from straight up and down.

RVDan · #5 01-03-2015, 05:58 PM

Same for the -6, the stick is forward when the elevator is neutral. The only thing I could think of is that the bellcrank pivot point is located wrong. The stick doesn't change the contact point in the rear much. Any pics of where the rod contacts?

WingsOnWheels · #6 01-03-2015, 06:55 PM

The pushrod is contacting where it passes through f-605, The rear spar bullhead. There are no clearance issues at the bellcrank. Since it is contacting in both dorections ( up and down elevator), it isnt a neutral point issue. I measured the weldment to make sure it was correct, no issues there. This is a later fuselage kit, there have been a few places where vans changed to rv-7 parts that dont quite work. I not sure if there have been any changes in this area, ill have to consult my old vs new plans.

ChiefPilot · #7 01-06-2015, 01:17 PM

I had the same problem on my -6A. Van's suggestion was to trim until there was no binding. I didn't need to remove much - perhaps 1/16th of an inch - and filed out the tooling marks.

gyoung · #8 01-06-2015, 04:45 PM

Enlarge the hole, just don't cut into the carry-through strap. Hopefully you got the strap low enough on the bulkhead to give you room.

Ralph Inkster · #9 01-06-2015, 09:38 PM

I imagine you have adjusted the up & down elevator stops per the manual, for max linkage travel?

WingsOnWheels · #10 01-07-2015, 05:26 AM

Thanks for the replies. I spoke to Ken at Vans on Monday and he said I could trim more from F-605 and could also trim a little from the yoke on the control stick weldment to keep it from hitting the rod end at full up elevator travel.

I did a little bit of trimming last night and played with the pushrods some more. Since the hinge point for the control sticks is off-center, I bought myself a bit of clearance by making the sticks more vertical in neutral.

At this point I can solve the binding at F-605 and at the rod-end. However, I find that the pushrod break the plane of the floor buy ~3/32" at full down elevator travel.

If there are any RV-6 building that happen to have there floor center cover open for maintenance, could you send me a picture showing the position of the control stick weldment at full forward and full after travel? Also, could you let me know how much clearance you have to the floor at full down elevator travel?

The place where I have an issue is where the seat slopes down from F-605 and then goes flat before sloping up to F-604. Here is a quick MS paint drawing to show the issue.