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My seat flexes when I enter the cabin by stepping onto the seat. Then once seated the travel of the controls, while not blocked, do scrap the bottom side of the seat in the middle. I also an not comfortable with how far the controls come into my body.

Has anyone had to build stronger seat structures which hold the seat higher in the center? If so can you supply details.

1labelloj wrote:My seat flexes when I enter the cabin by stepping onto the seat. Then once seated the travel of the controls, while not blocked, do scrap the bottom side of the seat in the middle. I also an not comfortable with how far the controls come into my body.

Has anyone had to build stronger seat structures which hold the seat higher in the center? If so can you supply details.

Hi. The only change I made was to make mine of .032 instead of .025. Is yours a flying aircraft, or are you still building? Once my seat cushions went in, I've never had any issues with the seat. It spans between two sets of hinges and is therefore a "sling." I have the lowered seat mod, so my seat is even lower than the "stock" seat.

Hi all,
This has been mentioned a few times in posts. Years ago when we were building, we met dave webber from dynon on the flightline at oshkosh with his red sonex. He gave us a tour of his plane and mods. One thing he mentioned was beefing up the seat pan. We had ours built already so we took some .020 or .025 and doubled it up Back and bottom. Really stiffins it up. Also later added alum angle on bottom underneath sides to prevent flex, as we added the dynon autopilot servos . The roll servo is the SV-42 EL. Extra long arm. Standard servo arm wont work. Too much throw each way, the software wont accept that much arm travel. Space is tight underneath(legacy sonex) not much flex can rub on controls or autopilot arms. Its an easy mod, just make the two sheets to size, and a rivet pattern to look good. Will have to relief cut openings for the stick opening(s) to match up.

WaiexN143NM
Michael

I used a .125 aluminum angle across the underside supported by both the skin and supported by phenolic on top of the landing gear legs ( i have a tri gear).

I plan on installing the Dynon autopilot system this winter and would like to provide this additional stiffness and support for the seat structure.

Does anyone have photos of this work that they can post or PM?

Thanks in advance.

I was at the hanager today, here is what I did to beef up the lower seat area - basically a 1/8" alum angle, added a .060 doubler for the skin to provide support for the "L" brackets. I also used 1" alum tube and riveted to the alum angle for more rigidity.

https://www.dropbox.com/s/x489o8uvvtsnk ... 5.jpg?dl=0

https://www.dropbox.com/s/vuurjucymu4t1 ... 0.jpg?dl=0

https://www.dropbox.com/s/8elw5on8uvg18 ... 6.jpg?dl=0