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I have been thinking that if I mounted the vertical tail to the fuselage with machine screws instead of rivets, it would be very simple to remove if need be. Has anyone else given this any thought?

Hi,

Why would you want to do that? Keep in mind that the engineers at Sonex determined the correct number and type of rivets to hold the tail under expected loads. Screws will provide a different strength. How many would you need to be equal to the rivets?

I've owned my OneX for about 5 years now and have never had even a remote reason to remove the tail.

Just my 2 cents. Build to the plans. It's faster and IMO safer.

-- Michael
OneX N169XE
author of the 'Flight Data Viewer'

Hi,
I don't think machine screws should replace rivets in structural parts of the airframe.
I have replaced the rivets on a one to one basis by small bolts and nuts on both sides, see pic. The holes were drilled to the correct diameter and the nuts received a dot of inspectors paint to check for tightness during inspections.

You have done exactly what I am thinking about doing. I would use #6 screws with nylocks. The only problem that I can foresee is that the threads only supply a percentage of fill for each hole. On the other hand, the SS rivets most likely don't swell to fill the hole either and there should be slop with a #30 drill. Anyway, I haven't mounted my tail yet but that is a lot of rivets to remove if I would want to remove the tail and the screws would make it easy by simply drilling out the fairing rivets. Thanks for your input, I am going to continue to think it over.

Actually the Sonex rivets do swell to fill the #30 drilled holes. Some other rivets like the ones that Zenith uses do not.

David A.

DCASonex wrote:Actually the Sonex rivets do swell to fill the #30 drilled holes. Some other rivets like the ones that Zenith uses do not.

David A.

Indeed, I've drilled out enough of them to see that the part of the rivet that's inside the hole has almost a machined look where it has swelled against the inside edges of the hole.

This actually brings up an old point about not using too high a pressure on your rivet gun so it takes half a second or so to fully pull the rivet (versus a super quick pull), as a fast pull will work-harden the rivet more quickly during the travel distance and might not allow full swelling of the rivet. I think Jeremy had made a video about this somewhere.