So we are supposed to cut a slot in the aileron leading edge skin for the center bearing bracket. No dimensions or details given. No biggie I can get creative on a slot width and can even find the center point w/ ailerons neutral but I am struggling to find the recommended aileron deflections, up/down, to decide on the slot height. Seems I've seen them somewhere once upon a time but it eludes me now.
( in a whisper ) if you can point it out to me I promise I wont tell anyone else the top secret numbers.

Hi Flydog,

On page 12 of the "assembly manual" under the heading "Control System" item #8 describes the minimum aileron travel as 22 degrees up and 16 down.   Shhhhh

However you want to be sure the slot is cut long enough that it does not act as the "control limit stop".   IIRC I kept cutting the slot longer until the controls could move to the limit (which seems to be when the teleflex cables "bottom out" and then made sure the slot was just big enough to accomodate this amount of deflection - and also verify this meets the minimums of 22 and 16 degrees.

When the controls are detached (such as removing a wing) care must be taken so as not to deflect the aileron so much that this slot is "torn longer" by overdeflection resulting in the slot "colliding" with the aileron hinge strap and elongating it.  If this does occur however, it is probably only a minor inconvenience and not major damage.

In searching the depths of my memory more deeply I'm thinking that the limit of control movement is not the "bottoming out" of the teleflex cables but rather the "collision" of the triangular aluminum plate mounted to the torque tube (the plate that the aileron cables connect to) with the wooden member that supports the front edge of the seat.  This member can have "extra wood" glued to it to limit the control movement to something close to the "required" degrees of travel.  This is a better control limit stop than bottoming out the teleflex cables.  In any case the slot in the aileron leading edge should not serve as the control travel limit.  This slot should allow for the rotation of the aileron until something that is designed to serve as the limit of travel actually engages to limit further travel.

Tnx Fenix
Guess I skimmed the manual too fast. See it now. Will gestimate and create a slot at this point for those deflections and fine tune at final rigging.
Regarding control stops, Vaughan Askue in Flight Testing Homebuilt Aircraft, recommends to have a limit at the control being moved and the control doing the actuation. I am not too worried about having a stop at both ends. I'd recommend this book to anyone flying exmental or ultralights even if they did not build it themselves.

I think the (actual) aileron control stopping travel ends up being your Knees/legs being hit if you move the stick full right or left.

The limit is likely your knees when flying, but if a gust of wind blows the aileron while tied down without a gust lock you want something to "take the hit" that is intended to do so.

I have seen plans and planes with control limits installed at either end of the system.  My Hatz calls them out at the control stick and my RV has them on the ailerons.  If you installed them at both ends it seems unlikely you'd get both of them to "engage" at exactly the same time so only would be "in operation".  However on something like the rudder (as it is usually cable actuated) it is good to have a positive stop at the rudder end as well, again in the event of being blown by the wind while tied down.

Vaughan's book is very informative and highly recommended by many experienced aviators. I've bought it twice because "something" happened to my first one.  I would not contest anything he said but might add that if the control limit is at the control surface the pilot's hand force is then applied to the entire control system after the stop is reached.  If the control stop is at the control stick the force of the pilot stops at that point and does not stress the entire system.  I discussed this with an engineer however, and his position is that the control surface can apply much more force to the system than the pilot can and that is why the stop should be at the surface.  However it seems to me if the control surface was hitting its stop on its own that would be due to something like flutter, and the cause has already been lost.  My non credentialed opinion is that as long as you have a control stop you are far better off than the limit being something that is not really intended, designed, or capable of limiting further travel without damage.   Let me repeat that I am not an engineer and I'm pretty sure Vaughan Askue is!  So he wins.

Quoted from Fenix

... I discussed this with an engineer however, and his position is that the control surface can apply much more force to the system than the pilot can and that is why the stop should be at the surface. ...

I don't believe that our control surfaces could overcome our ability to resist their movement. Maybe so in a B17 but not in a MiniMax.

In the UK it was mandatory that the control system was able to handle the maximum force that the pilot could reasonably apply, and without breaking. Presumably so that if the pilot realised the error of his ways he still had control remaining to put in the correct control input, if there were one.