Aileron stops

25 Sep 2004 Aileron stops

The Van’s suggested way of doing the aileron stops is probably quite good, but I felt it was a bit complex, and it seems like it would be hard to get the stops installed in exactly the right place. I planned on waiting until the last moment to install them, because I was not too sure how to do it right.

After installing the ailerons, and looking at all the controls, I found what I believe to be a better way to do the control stops, and that is with a bit of delrin rod, installed over one of the spacers that are on the bolt that connects the small aileron pushrod, on each aileron.

I went to ACS on the web, and bought several different sizes of delrin rod. I was not sure what diameter would be best. I would have bought the delrin rod at McMaster-Carr, but they only sell it in 5 foot lengths, and I need about two inches. I bought these from ACS – they are one foot long, their minimum quantity for this stuff.

Here I’ve drilled a hole in the center of the rod so that the spacer can go in there. Turns out it’s about 8mm, which is good, since I have some excellent metric drill bits. I chose the 0.5 inch diameter rod, the smallest diameter that I purchased. The largest I bought was 7/8 inch. I’m sure I’ll find something to do with this stuff.

Here is the finished sleeve of delrin with the aluminium spacer in there. Perfect fit, with just a bit of slow rotation allowed.

Here is the delrin sleeve installed. What I like about this installation is that it is delrin against aluminium, not metal against metal. The delrin is right next to the pushrod, which means that there is almost no leverage on it. All the force of the pushrod on the delrin goes right to the aileron mount bracket, which is very solid. This bracket is where the Van’s aileron stop would have gone anyway.

The result is very solid, and I believe pretty elegant. I’ll have to suggest this to Van’s, since it more closely matches their philosophy of being clever, simple, and cheap.

Update: 20050424 – Just to clarify, one of these delrin stops needs to go on each aileron.