R

rv9aviator

Well Known Member
I am trial fitting the aileron tubes to the sticks and using Vans dimension of 94-7/32 center to center the stick is over to the right about 15 deg. instead of being centered or straight up and down. I might be able to get it centered but the bearings would be screwed way out further than normal. I don't think it would be a safe thing to do. They seem to be about an inch short. Has any one else had this problem. The only fix I see is to make new tubes. Mine measure 94-1/2 right now with the bearings screwed half way in which is a little over a 1/4 inch more than the drawing and it is still short. I could make up some of the difference by lengthening the bell-crank to aileron push rod tubes but then those rod end bearing would be screwed out further than normal. Anyone out there got some words of wisdom for me?
On the good side I got to see my electric flaps go up and down under power today. I was so excited I had my wife come out and look. She tried her best to look excited too.:) Oh well.
 
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Jim,

Something doesn't sound right to me.

My rods were cut to Van's dimensions and fit almost perfect.

Double check the length of the smaller push tubes that go from the bell crank to the ailerons and make sure they are the proper length.

While you are at it, make sure you have the bell cranks on the correct side and in the correct orientation.

Getting them rigged was a pain for me and took me some time to get correct.

Congrats on the flaps! You are almost there from the sounds of it.
 
I will double check the length of the short tubes and see if there is a problem with them. I'm sure the brackets are on the right as I've installed a TruTrak servo on the right wing and the left is the one I'm fighting right now. I haven't even tried the right side yet but I remember going over the brackets in detail making sure they were right.
Thanks
 
too short

Yeah Jim, mine was a qb and I cut the tubes EXACTLY to plans, If you search through the old post, I told others to not cut them till the rigging stage, I ordered new tubes , mine might have worked but I didn't like the amount the bearings were screwed into the cones, a few threads
on each end was not enough for me.. you might double check
but thats what happened to me.. I didn't want to worry about it
later..


Danny..
 
Man I wish I would have seen that post. I have checked everything I can think of and they are simply too short.
 
old post

Jim, I just did a search for those old post, search "Aileron push rods" and
read the thread, I think the other guy had a stick weldment that was
bend or crooked stick, and a few others posted simular issues.. also
I made a 2nd alignment bracket so I could have both rigged at the
same time.. doing it alone it really helped having two of them
one on each belcrank,


Danny..
 
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pushrod too short

Mine was too short also to keep me in the warm fuzzy feeling...probably about two threads worth. I went to the MC Masters catalog and ordered two more rod end bearings with longer shanks. It sure made me feel better knowing there's lots of thead screwed in the rod ends.

Good luck
G.P.
 
same boat

G,
Would you post the McMaster part numbers on the long shank rod bearings?
Steve
 
At least one of the pre-first-flight inspection checklists I've looked at wants the pushrods long enough so that if the jam nuts back completely off the rod end bearings, the control rod will not fall off if it rotates all the way to one side. It mentions adding a second jam nut to limit travel if necessary.

I think one of mine might fail that test, but I have to verify the bellcrank positions first.
 
Problem solved

I finally figured the long aileron tubes would work even though there is more thread showing than I would like. The rod end can't unscrew all the way out because the jam nut will stop the travel with a few threads still in the tube end. I am making new aileron to bell-crank push pull tubes and will make them 1/2 inch longer than the drawing calls for. That should take care of the problem. I would definitely wait until I was ready to rig the wings before making the tubes up. If I had it to over again I would make the large tubes 1/4 inch longer and the short tubes 1/2 inch longer. Keep in mind that is working on my RV9 but your mileage may vary. I did call Gus and he said they have been the same dimension since 2000 and no one has called in about them being too short so it must be something I did wrong.:rolleyes:
 
Jim,

On the long tubes, are you going to add a second jam nut like Mike suggests, to keep more threads in the tube end? Could you add a second jam nut to the short pushrods, too, instead of having to make new ones?
 
That would be fine on the long tubes but there is not enough threads inside the tube to drill for the safety wire as it is. I had some 1/2 inch .035 wall 4140 tube laying around anyway so I am just going to make new ones.
The extra jam nut is a good idea though.
 
rv9aviator said:
I did call Gus and he said they have been the same dimension since 2000 and no one has called in about them being too short so it must be something I did wrong.:rolleyes:
Click to expand...

That is the type stuff that does frustrate me with VANs - this is a 'common' issue / multiple people have suffered - basically the CAD drawing is right for exactly 50% of the rod end bearing in, it would make FAR more sense to have 75% in for the 'norm', reducing the length is easy and safe and you then have the option to lengthen. Ours was with quick build fuse and wings - not something we could get wrong - and yes the tubes were cut +/- 1/64".

I would agree adding 1/4" to 1/2" to main wing push rods would help, and 1/4" to the wing/ailerons. We also went the welded route for the wing ones just seems a neater end result.

YMMV,

Carl
 
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