substituting pop rivets

[prkaye]

In general, is it acceptable practice to substitute pop rivets for regular rivets if the need arises? There is a place at the front of a HS tip rib where I could not make a regular rivet work, even an oops rivet (the skin kept pulling away from the rib). I got a pop rivet to work.

Will the pop rivet have sufficient strength; is the difference only cosmetic (it's on the underside of the HS so I'm not concerned about the cosmetics)?

A related question, if an inspector sees a rivet he doesn't like, if this is in a place that cannot be accessed for bucking because the structure has been closed off too much, can the rivet generally be replaced with a pop rivet? (has anyone experienced this?)

[Build9A]

I doubt the inspector will make you replace a pop rivet. As you probably know some homebuilts are constructed entirely of pop rivets. I know the area you are talking about on the HS and lots of us have problems with those 2 or 3 rivets. I'm not a DAR but I wouldn't be afraid to fly with a few pop rivets. In fact, I used a few cherrymax pop rivets in the forward fuselage where (in my opinion) they were next to impossible to buck, filled them in and painted them. No one ever knew until now. Jack

[Mel]

Blind rivets are approved most everywhere on the RV with the exception of the main wing spar. Be sure we are talking "blind rivets". "Pop" rivets are a hardware store variety and should not be used anywhere on an aircraft. Blind rivets used in aircraft should meet some kind of spec. These may be "Cherry", AVX, or other brands.

[chaskuss]

Originally Posted by prkaye

In general, is it acceptable practice to substitute pop rivets for regular rivets if the need arises? There is a place at the front of a HS tip rib where I could not make a regular rivet work, even an oops rivet (the skin kept pulling away from the rib). I got a pop rivet to work.

Will the pop rivet have sufficient strength; is the difference only cosmetic (it's on the underside of the HS so I'm not concerned about the cosmetics)?

A related question, if an inspector sees a rivet he doesn't like, if this is in a place that cannot be accessed for bucking because the structure has been closed off too much, can the rivet generally be replaced with a pop rivet? (has anyone experienced this?)

As Mel mentioned earlier, the use of a single 7/64" Avex rivet to replace a 3/32" solid rivet would probably not be a problem. Most of us have one place or another where we simply could not proper buck a rivet. If you check the shear strength info, you'll find that to have the same strength, you actually need to go up one size (ie replace 3/32" solid with 1/8" Avex) to maintain fastener strength.
So, if you wanted to replace a row of 3/32" solid rivets with Avex blind rivets, you should increase the rivet diameter by one size. Cherry Max blind rivets however, DO have the same strength as their solid counterparts. Alas, they are not made in 3/32" diameter.
Charlie Kuss

[prkaye]

Which brand of blind rivets is it that Vans supplies with the kit? I had some that came with the kit to use for the middle main rib to spar rivets of the HS.

[chaskuss]

Originally Posted by prkaye

Which brand of blind rivets is it that Vans supplies with the kit? I had some that came with the kit to use for the middle main rib to spar rivets of the HS.

I am unsure of the brand, but they are Avex quality.
Charlie Kuss