Rear seat attach

[cessna170bdriver]

Miles
Instead of screws, I use hex head bolts and a 3/8” socket on a 1/4” ratchet to tighten and remove them. Much easier than screws.

That is actually a structural Phillips head bolt (go back and take a look at the picture in my first post). It’s the one that Mountain Airframe installed during the rebuild. I was able to put it in with a Phillips hex drive bit and a 1/4” ratchet. I don’t think a hex bolt would have been any easier. The hard part was just getting it lined up and the threads started in the anchor nut.

[Bruce Fenstermacher]

An old trick is to find a screw or bolt an 1/8" longer and sharpen it like a golf pencil, so that it self aligns in the hole. Easier said than done cause you also need a good grip length.

[N2625U]

An old trick is to find a screw or bolt an 1/8" longer and sharpen it like a golf pencil, so that it self aligns in the hole. Easier said than done cause you also need a good grip length.

Then run a die to smooth out the threads of the part you sharpened. I ran the die on the bolt first then sharpened the end and ran the die out smoothing the threads. Did that on mine and it works great.

[GAHorn]

The tubular seat frames are often distorted and it's likely never corrected in any kind of "jig". A heavy person** can bend the frame ever-so-slightly which results in this sort of mis-match and the seat frame is the likely culprit. But correcting it can be a real "bear" with the most common solution being what has occurred in this example... a little "encouragement" applied to the seat with the hardware not given final tightening until all are started.

Cessna would have done us all a favor if they'd installed that rear seat on tracks but that has it's own complications as we all know.


** The 170 lb FAA person these airplanes were designed around rarely exists these days. The more likely 220+ is common today and it results in twisted seat frames and cracked seat tracks. (I recently observed a single engine Cessna disembark only two guys who likely exceeded the entire design of that floor. And my own weight isn't very close to what Cessna planned-for.) The floor beneath the pilot's seats and the cabin entry-steps and the upper door hinges (oft used to support weight when entering/exiting) all suffer from it. Addt'l stress is suffered by the front seat-backs especially when someone raises their butt by leaning back on the seat-back reaching for the seat belts they're sitting on. Seat back failures during takeoff/climb can and has resulted in accidents. Inspect yours often.