Set Screws for the Aileron Bell Crank

[Stogie6]

Good morning all Onex builders out there. I was completing the adjustments to the set screws on the aileron bell crank assembly (drawing ONX-W21) for both wings. In order to ensure zero "slop" when the ball and paddle mate, you adjust the 5/16 - 18 thread set screw accordingly. My issue is when it is all said and done, I have zero thread visible on the back nylon nut. For that matter, only about a third of the screw is engaged with the nut. I would like to see at least two threads projecting out, but I am not able to get this to happen. I built per plans - followed all details, etc. So, long story short - does anybody know of a supplier that has a longer set screw (1 1/4 inch or better) that I can replace the original set screw with? I am continuing my search on the internet, but thought I would ask. I may have to make one (actually - 4)!
Thanks for the input.

[Onex107]

Instead of taking all the adjustment on one screw, can't you take some on the other one also, so both screws take some of the adjustment? It shouldn't effect the total aileron movement. Mine needed very little change to be tight.

[Stogie6]

Instead of taking all the adjustment on one screw, can't you take some on the other one also, so both screws take some of the adjustment? It shouldn't effect the total aileron movement. Mine needed very little change to be tight.

I will go back and review, but I adjusted all set screws, not just any one specific. Made a turn on the allen wrench, tested the fit, and so on.
Thanks for the post.

[Stogie6]

Here is the answer from Tech Support. I guess this could make sense...

The nut on the backside of each paddle is providing back-up duty to the nut on the “outside” of each paddle. Our prototypes are flying with only a single nut on the “outside.” We do not feel a longer swivel is necessary to get more engagement of the aft locknuts.

We looked and our supplier (MacMaster -Carr) does not offer a screw longer than the 1” screw we provide.

Sonex Aircraft Tech Support

Sonex Aircraft LLC
511 Aviation Road
Oshkosh, WI 54902
Tech Line: (920) 230-TECH (8324)
Mon, Wed. and Fri. 10 AM to 12 AM and 2PM to 4PM CT

[kmacht]

If you have a Fastenall by you they have 5/16-18 x 1.5" set screws or you can buy them from them online. P/N 0177704.

Keith
#554

[thomasjones42]

This message string is almost a year old but I just encountered the same problem. Just for info I found that the Fastenal part number listed earlier does not have a ball end as do the Onex supplied screws nor did Fastenal have the ball end screws. I did find online an Item # 74698515 at MSC Industrial Suppy that has a cap bolt head, a ball end and a length beyond the head of 1.25 inches. They are not cheap (about $7.00 each plus shipping) but are stainless steel and I find that they allow me to use both lock nuts and still have thread left for additional adjustment. MSC calls them "Round tip ball clamping screws". Other sites call them "ball ended thrust screws". As Sonex pointed out earlier, the longest I found anywhere online with the same head they supply was 1 inch. For what it's worth.

Tom Jones
ONEX #133
Aerovee Turbo

[inventor]

I was installing my ball end set screws the other day and noticed that one of the balls is missing. I don't know how it fell out but it could be a major problem if it happened after installation since the end of the set screw with no ball is a sharp gouger. I am thinking of using something with a rounded nylon tip and doing away with the set screws. I am wondering if anyone else has had this problem or found an alternate solution.