Countersunk pull rivets for nutplate?

[Mtbguy]

Hi everyone
I recently bought a new to me RV3 out of state. I’ve been traveling back and forth to work on it periodically. It’s temporarily parked outside until I can get it back home.
The original builder did a good job with construction but when he built it riveted on (each) wingtip with approximately 80 (yes 80) pop rivets per wing. I want to open up wingtips for doing some work to the nav lights and general inspection. I don’t plan on keeping the plane long term (already have an RV4), but don’t want to botch things up either.

I’m thinking drill out the existing rivets and then countersink holes around 40 holes in each wingtip, use a backing strip, and then fill in old alternating holes and touch up. Does this seem like a good plan? (I’m not a builder yet but getting started soon). I was hoping to use soft pull rivets to install the nut plates if possible since it’s an outdoors modification with limited tools available.

Thoughts or ideas.

Thanks!

Rick

 

[Ironflight]

The normal way to make wingtips detachable is much like you suggest with the exception that you don;t countersink th emetal at the tip of the wing, you dimple it. You then countersink the fiberglas underneath it to make a flush joint. Yes, you can use pulled rivets to attach the nutplates, but in most cases we use soft countersunk solid rivets (or normal harness ones - either work).

 

[Mtbguy]

Thanks Paul

 

[jacoby]

You'll come out ahead using solid rivets even if you have to buy a hand squeezer (and optionally sell it later). At current prices you'll have around $1000 in CCR rivets for those 80 nutplates.

 

[Ironflight]

You'll come out ahead using solid rivets even if you have to buy a hand squeezer (and optionally sell it later). At current prices you'll have around $1000 in CCR rivets for those 80 nutplates.

To be fair, he certainly wouldn’t need CherryMax rivets for this - Cherry N’s (look up a CCC-32 on Spruce) are $0.20 each, so more like $32 for 80 nutplates…..

 

[Walt]

Check out the CCR244CS3-02 (or -03). This is specifically designed for nutplate installation.
(reduced head/small countersink requirements)
I usually pick up a bag at one of the Osh vendors.

Cherry Nutplate Rivet - 100°, Flush Head, Corrosion Resistant, Diameter: 3/32", Grip Range: 0.063" - 0.125"

 

[jacoby]

To be fair, he certainly wouldn’t need CherryMax rivets for this - Cherry N’s (look up a CCC-32 on Spruce) are $0.20 each, so more like $32 for 80 nutplates…..

Are those actually 3/32"? They're listed as replacements for the MK319BS which are a 7/64" rivet. I can't find any actual specs on them with a quick search.

I was looking at the CCR-264SS cherry "nutplate" rivet. Not the cherry max rivets. (The mandrel actually pulls out of the CCR leaving just the barrel). The CCR are ~$6/ea right now.

The CCC also have a 120° head vs 100° for the CCR. But that doesn't matter for a nutplate.

 

[Jonnyb]

I tend to use the CCC-32 for nut plates where needed. Or the smaller headed opps rivets

 

[rockyfatcat]

I bought a -7 project that similarly had the wingtips pop riveted on and no lighting whatsoever.

I thought I could very carefully drill them out. What actually happened was when the drill bit hit sheetmetal, the bit grabbed and tore an ugly hole (times as many rivets)

I ended up installing piano hinge material as a connection between the wing & wingtip and using oversize soft rivets hand squeezed to secure the hinge.

Hindsight is 20/20. To do it again, I would load a slightly undersized 1/4-28 threaded drill bit (like for a 90 degree air drill) in a birdcage and carefully set the depth before starting.

 

[Ironflight]

Are those actually 3/32"? They're listed as replacements for the MK319BS which are a 7/64" rivet. I can't find any actual specs on them with a quick search.

I was looking at the CCR-264SS cherry "nutplate" rivet. Not the cherry max rivets. (The mandrel actually pulls out of the CCR leaving just the barrel). The CCR are ~$6/ea right now.

The CCC also have a 120° head vs 100° for the CCR. But that doesn't matter for a nutplate.

Well I’ve used them a bunch for this kind of thing….I have never actually looked up the spec to be honest!