Can anyone tell me where the flaperon stops are.
Also I dont have the last page of the drawings 75-za-7 06/10 control deflections can anyone help with this
Thanks Hamish

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Welded a 1" extension!?!?!!  EGADS!!! 

I sure hope I don't have to do something that drastic.  I'm pretty sure I will have to have the main sticks lean a bit which will really suck, but like John says it shouldn't be too much of a problem.  The right wing is the problem, it can go down about 16 degrees, but only goes up about 6 from neutral. 

I also had issues with the slot in the fuselage for the flaperon vertical rod. So far I've had to widen it about 1/8 or an inch and cut out about 1/4 more from the top so it would let the rod have full movement.  Don't know why it would be so off but from what I've read I'm not the only one with these issues.  Hoping to have it all figured out by the weekend!

Didn't do any welding. Just used an extension (female threaded) from hardware store, and screwed in threaded portion of bolt with head cut off.

Thanks for clearing that up, don't know where I thought I saw you welded something to it... LOL

That might be a last resort option for me as well if I can't figure this out.  :(

1/8 of an inch? I think you'll need to step out the surgeons perspective into the carpenters mindset. I attached a picture to show how much I took out, and it's probably 8 of those 1/8s, minimum. It seems there's quite a bit of geometry that goes on with the whole set up, and quite a few ways to get the same equation. All I know is I finally got it to work, but I also have more down flap deflection than normal, which I'm ok with, as I can adjust that later if I want to take that out.  

Hope the picture helps.

LOL, well I only started carving it out, I'll probably have to take more.  I'm thinking that zen put that slot in there as a general "idea" of where it should go and not as specific plane!  I wonder if anyone has ever gotten this working without having to hack that hole up? :(


What I found worked for me was to move the bolt up and down and mark with a Sharpie where the spacer contacted the edge of the "banana" slot. Then, I took a Dremel with a coarse aluminum oxide drum and sanded that area. The sanding action allowed me to easily keep the slot's contour smooth.  Eventually, the flaperon could move freely and the spacer/bolt cleared the skin. But you've got it right - that slot is only an "approximation" of the final result!


Well I finally got the deflection close enough to what I need!!!  What a nightmare this was to do!  The right wing did not want to get the up deflection that was required no matter what I tried.  I finally got it to 11.9 degrees up on the right wing and that's at the absolute limit that I can get the tie-ends in safety.  I'll take it!!!

One issue causing me grief was the elevator cable... when connected it created a bounce when the sticks are pushed to the right, so I disconnected it and it really helped get everything adjusted to work smooth.

The dual sticks were part of the problem... they just didn't allow the play I needed in the lower ends due to the "box" setup at the bottom of the sticks.  I had to grind the bottom side of the box a bit on the left side and the adjacent top area of the "box" to let the stick move a bit more to the right.  That gave me an extra two degrees or so.  Shouldn't be noticeable once I repaint the bottom of the sticks.  Don't know if this would work on the "Y" stick as I never installed it and don't know how it's mechanized at the bottom, but I'm pretty sure it wouldn't be like this... anyways, it works. 

NO WAY should this be that hard to do.  Putting threaded ends on the attach arms below the sticks would make this go away!  I'll probably try and make my own once I get a new welder... an entire Saturday blown to do this...cry!

Everything is tight but there seems to be a hair of "slop" in the flaperons, I can move them up and down, maybe one or two degrees without the sticks moving... this normal?

I don't know why you had so much problems - like I said, I had zero problems setting up my dual sticks and zero modifications! Maybe 'cause they are a low-volume option there's more variation in the fabrication? Or, there could have been a problem down-stream of the stick that forced you to modify the controls??? Who knows!

Almost no controls are perfectly linear in movement-response. Seems like mine have a degree or two of "wiggle" in them, but nothing that you would interpret as "sloppy" in-flight. Sounds normal to me.



Redid the flaperon adjustment yesterday.

1. magnetic level to ensure control shaft is vertical and centred.

2. Adjust short rods so that bellcranks are parallel with tube.

3. Adjust long rods till both flaperons are neutral with stick centred as measured by magnetic level (this takes forever).

4. With a digital level, and not moving the aircraft, measure the angle of the to surface of the inboard flaperon from horizontal. mine were about 19 degrees. Now put the flaps all the way down and measure again, you should have 15 degrees of flap(ie measuring 19+15 =34)

5. Move flaperon up and measure deflection angle from horizontal on one side and down on the other.

6. Subtract angles and see if you have 13 degree deflection up (you wont) so chew away at the slot until you do.

7.Repeat 5 and 6 the other side. the same with flaps up you have to chew on both ends of the slot. Make sure you get more than 13 degrees because you don't want the bolts to touch the skin at all under all flight conditions-so that nothing can lock.

9. mark the limits of the controls with a sharpy where the stops fit. Pull everything apart. mount the stops oversize, then file forever until you get 13 degrees up and down both sides.

9. mark the limits of the controls with a sharpy where the stops fit. Pull everything apart. mount the stops oversize, then file forever until you get 13 degrees up and down both sides.


What worked for me was to go ahead and install the stop's mounting bolts and put some grease paint (actually, I borrowed one of the dear wife's old lipsticks!) on the end of the bolts. I then used a Mark I eyeball to "guesstimate" the position of the stop and lightly touched it to the bolt ends, to make grease paint marks where the holes needed to go. I then drilled the stops (I also lightly radiused the edge that contacts the tab on the torque tube) and installed them. I was very fortunate in that I think I maybe hit one of the stops a few light file strokes, but they were really, really close to where they needed to be!

My fall-back method was that if the stops were really off and needed adjustment, I could just slot the bolt holes in the stop and adjust it that way ... really not a bad method to use, anyway, vs having to do a bunch of filing!




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