I did not build my RV-10 but I have owned it for over 7 years now and have made many modifications and upgrades to it. One minor problem has been the door struts. I have purchased the Van's heavy duty ones a couple of times but I fly the airplane a lot and the doors are opened and closed hundreds of times each year. These struts usually work OK when it is warm but in the winter months they start to sag. I am in the replacement mode right now and came to the RV-10 forum and searched for door struts. Nothing recently was posted but going back a few years there is a lot of information and based on that I ordered the Bansbach struts that should be here this week. During this search several people posted pictures of their installations and I couldn't help but notice that one person had the struts positioned one direction (non-movable end on the air frame) and the other person had it position exactly the opposite way. I wondered which way was correct so I got my plans out to investigate. It turns out that the plans show that the non-movable fixed end of the strut should be attached to the air frame and the other end attached to the door. My question is does it really matter and if so why? Just curious.................