Cherry Max rivits ? ?

[autoglide]

A friend of mine asked me to look at a -3 that?s for sale at our airport, as I helped building one some 30 yrs ago.
Was built ....first flew 25 yrs ago. Construction seems to be good....no tail feather cracks, BUT was riveted (skins/bulkheads) with cherry max rivits.
The riviting job is good.
He won?t be doing aerobatics at all. I?ve never seen an RV built w cherry max rivits....should he be concerned?

[rv7charlie]

There must be more money in the rivets than the rest of the kit....

IIRC, true cherrymax rivets are supposed to be the structural equivalent of a driven rivet. Relatively easy to look up the milspec for them to compare. If they're real cherrymax rivets, I'd think the plane would be as strong as a stock build, but heavier and perhaps a bit more 'draggy'.

I once saw an in-process -4 being built with pulled rivets. It did look....weird.

Charlie

[n982sx]

So unlikely to be Cherrymax rivets that sight unseen I'm willing to say they are not.

As to pulled/blind rivets there are many many different types, all with vastly different strengths.

Sonex aircraft are built with stainless steel Cherry 'N' rivets. The RV-12 is built with pulled rivets, I believe Advel but I'm not sure. The Zenith kits are built with pulled rivets.

The Sonex aircraft are +6 -3g aircraft. The rivets are 1/8 inch diameter of various lengths.

So it all depends on the specific rivets and size of those rivets that the aircraft you're looking at is built with. Anyway to find that out?

[JoeLofton]

You need to know the type of Cherry rivets used. Some types require precisely drilled holes for maximum clamping effect, others have a hole-filling property similar to driven rivets and holes need not be quite so precise.