Sonex ?? Pop Rivets?

[el con]

I'm thinking of building a Sonex. Looks easy to build, inexpensive,fairly quick for 80 to 100 hp ,and fuel efficient.
Both a good friend ( w/RV-8) and my mechanic say they have concerns about all those pop rivets.
Anybody out there have some input on the plane or the pop rivets?

 

[CJones]

I'm thinking of building a Sonex. Looks easy to build, inexpensive,fairly quick for 80 to 100 hp ,and fuel efficient.
Both a good friend ( w/RV-8) and my mechanic say they have concerns about all those pop rivets.
Anybody out there have some input on the plane or the pop rivets?

Van's RV-12 uses all pop-rivets IIRC. And 'Van' is a staunch advocate for standard squeeze/hammer rivets, so someone must have convinced him pop's are OK.

 

[etsisk]

First of all, these are NOT "pop-rivets"! They are pulled rivets, but they are aircraft grade Cherry rivets. They are a known quantity and are well within spec for the forces that would be exerted upon them. There are some places on the Sonex where you have standard (pounded) rivets in use - primarily the spar caps, I believe.

You may decide to not go with the Sonex - but the rivets should not be the reason you don't.

The plane is really well engineered, the plans are simply astonishing - best plans, hands down, in the industry. There's a lot of builder support from Sonex and the computer boards, as well. Don't let the pulled rivets run you off.

 

[jmaynard]

I can't speak to the Sonex in particular, but the Zodiac is pretty much completely built with pulled rivets. (In this case, not Cherry, but Avex.) Nobody's ever reported problems based on them, and they contribute essentially nothing to airframe drag.

As long as you use aviation-grade rivets, things will be just fine, and they're a lot easier to get right.

 

[GigG601XL]

Go read this. http://www.zenithair.com/kit-data/ht-86-12.html

It is from the designer of the Zenith 601XL, 701 and several other things, including parts of the Concorde.

A&Ps look down on anything they don't understand and most know NOTHING about aircraft design.

RV builders look down on everybody.

I'm thinking of building a Sonex. Looks easy to build, inexpensive,fairly quick for 80 to 100 hp ,and fuel efficient.
Both a good friend ( w/RV-8) and my mechanic say they have concerns about all those pop rivets.
Anybody out there have some input on the plane or the pop rivets?

 

[kyleb]

Go read this. http://www.zenithair.com/kit-data/ht-86-12.html

It is from the designer of the Zenith 601XL, 701 and several other things, including parts of the Concorde.

A&Ps look down on anything they don't understand and most know NOTHING about aircraft design.

RV builders look down on everybody.

Not everybody. But those Zenair guys... aargh. ;-)

Anyway, pop rivets have their place in the world. Zenith designs (and Sonexes) have been around for a long time and there has been no indication that the pop rivets are a problem.

 

[wanttaja]

I'm thinking of building a Sonex. Looks easy to build, inexpensive,fairly quick for 80 to 100 hp ,and fuel efficient.
Both a good friend ( w/RV-8) and my mechanic say they have concerns about all those pop rivets.
Anybody out there have some input on the plane or the pop rivets?

"Pop Rivet" is a trademarked term; the Sonex doesn't use Pop Rivets. PULLED rivets, yes, but probably dozens of homebuilt designs do. I believe even some of the "regular" RVs end up using a pulled rivet or two.

Driven or pulled, as long as (1) The designer ensures his use reflects the lower individual strength of a pulled rivet, and (2) The builder uses *specifically* the rivets specified by the designer.

This last point is important. I bought 1/8" "Avex Rivets" from a local supplier. Several years later, I bought another batch from Aircraft Spruce. They were quite dissimilar.

Ron Wanttaja

 

[GigG601XL]

This last point is important. I bought 1/8" "Avex Rivets" from a local supplier. Several years later, I bought another batch from Aircraft Spruce. They were quite dissimilar.

Ron Wanttaja

Very true. When I first started building my 601XL Chris Heintz specificly called for Avex rivets that were made in either the UK or Canada. (I don't remember which because I got all mine from Zenith and they test each batch.)

 

[Henning]

Remember, not all pulled rivets are created equally. "Pop Rivetstm" are completely unsuitable in an application where any sheer force will be applied and are only good for a minor pulling force due to not being cored, and that the flaring bulb pulls up the center and flares the blind side of the rivet. I would not use them in any structure or on a stressed skin. There are however several manufacturers of pulled rivets (Cherry, Avex...) that make a product that I would not hesitate to use because the blind end pulls a flat, and that causes the rivet to squash and pull tight and firm, and then leaves the core in the rivet to protect against sheer deformation.

I wouldn't build a Sonex though because it's butt ugly.