SonexBuilders.net

Hi Folks

The tailwheel on my Sonex has quite a bit of rotational play in the top rod bracket, even with a new top bolt. I'm assuming that the through-bolt hole in the steel fuselage fitting has worn oversize. My question is, can this fitting be removed from the fuselage without de-riveting or is there another fix for this if it's a common problem?

Regards

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Taper pin will fix a sloppy bolt hole. If the hole centerline is aligned with the skin hole, then you could taper ream it from the bottom and have the pin nut on the top. I would do that before drilling out all those rivets.

Rick Caldwell
Xenos 0057
Taper pins instead of bolts

Check out the saddle clamp in my thread.
viewtopic.php?f=39&t=578&start=390

Also I bonded my tail spring into the socket. That would help as well.

Thanks Both

Yes the hole is aligned so I guess the taper pin is the easiest option and like the idea of taper pins generally in that sort of application where a bolt seems doomed to be sloppy. I’ve never used them so will try to figure out what I need.

Regards

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There is an article about taper pins here

http://www.sonexfoundation.com/uploads/ ... lation.pdf

Though the size is different it may be helpful

The one scary thing about that idea is you have to make the taper in a solid piece of Ti. Also you will be doing it freehand and not on a drill press.

Is a taper pin a good idea, Ti aside, considering one piece is solid and one is a tube? You are never going to be able to draw the pin in further than the solid piece will let you, which makes it hard to draw tight into the tube.

Are you guys using the good bit for drilling your holes? Step drilling?
I used double margin drill bits on all my critical holes. Double margin or stove burner bits drill a nice round hole.
I would also leave the shank of the smaller bit in the hole while updrilling. That would lock the two pieces together and prevent movement and missalignment.

Thanks all for the replies. I'm going to try bonding it in with Hysol first and see how that works before considering the taper pin approach.
Regards
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This past Sunday I drilled 3/16" hole with a carbide bit by hand using the Drill Rite Guide for my Flyboys tailwheel socket. Then I updrilled to 13/64" with a regular drill bit. Then I reamed the hole with a #1 taper pin reamer using my variable speed pneumatic drill. I went slow and used lots of cutting fluid. I also let things cool periodically. All came out fine. I now have a vertically installed taper pin located 1" down on the socket. The taper pin on the upper end was done on the mini-mill a few months ago.

I did the same thing years ago on my One Design tailwheel. No problems with it loosening. I also had a taper pin on the One Design elevator trim tab torque tube that was originally a bolt. It would get loose after a few years so I would ream a little on it and re-set the taper pin. Then it was tight again. It would loosen because of the thin walled tube used. This shouldn't be a problem with the thick walled tailwheel socket. My experience is that taper pins stay tight longer than bolts in torque tube type applications.

Rick Caldwell
Xenos 0057