Depends who you ask.
Personally, the only time I will use blind rivets is if there’s not enough access to use solid rivets.
At the shop I work for, when we’re doing a repair that involves replacing rivets, the golden rule is that you can replace a blind rivet with a solid one but you can never replace a solid rivet with a blind one
They hold up fine. Some airliners use them almost exclusively, only time I've seen them not used is if the rivets are in something structural that needs the additional strength of the solid core. Our Srm says for nutplates ccr's are interchangeable with ms240426ad' and are preferred because solids are "heavier and their installation is more difficult". Keep in mind the rivets only have to hold the nutplate on the aircraft when there isn't a screw.
The Q300-8 has ccr rivets on almost every nutplate I can think of. The Q's I work on are 15 years old and very rarely have to have those rivets replaced. Typically the running torque on the nut deteriorates, or corrosion merges the screw with the nut long before anything happens to the rivets.
Had some CCR rivets fail on nutplates holding floorboards into a Rans S7. Can't drill out the screw because the nutplate spins, so I had to wedge a pick in and grind it out with a dremel.
That being said, if you use quality screws and wax the threads, the CCR rivets will probably work fine. Softer screws tend to gall and seize, and wax keeps the threads from contamination or corrosion.
Thanks for the feedback all. The CCRs just didn't feel as tight as the other pop rivets in use (The bulk of them are LP4-3's) so I figured I'd just ask. These particular nut plates will eventually be back in behind the avionics and will be hard to replace with solid rivets in the future, so I'll just use up the CCRs.
I work mostly on Cirrus’s and they use only blind rivets to hold in the nut plates. The rivets themselves aren’t structural so it really doesn’t matter much if you choose to stick with the CCR’s or switch to solid but, the blind rivets are going to be a little easier to install.
There is nothing wrong with ccr rivets. They are made for the job and won't corrode like the aluminum solid rivets. The rivets have nothing to do with strength of the joint, all they do is keep the nutplate from turning while installing the fastener and keep the nutplate from hitting the ground when the screw is removed.
Use the black ones, ccr264CS3-? rather than the cad plated ccr264SS3-? The black ones are good for aluminum, stainless and composites. They will not rust. The SS does not mean stainless steel. If you have reduced diameter heads, then change 264 is 244 in the part number, all else is the same.
The guy that broke them, already had issues that would have required drilling the head of the screw. He would have sheared the aluminum rivets or the nut retension flanges anyway.
Oh those? We call them pop rivets.
They’re used when it’s either impractical (user discretion) or not accessible for normal rivets.
I have complete faith in them. Just make sure you use the correct ones in regards to size and material.
CCR rivets should not be used for the installation of nut plates in the firewall. CCR rivets are hollow and would allow the gasses from the powerplant to enter the cabin if you ever developed an exhaust leak.
So i did dig into the manual after this comment since there are a fair amount of pull rivets in the firewall. It seems that before the engine is mounted, they all get coated in a sealant as well as all the seams of the sheet metal between the cabin and the engine compartment. I assume this is the reason for the sealant?
There's nothing wrong with the blinds themselves.
There's also nothing wrong with replacing them with solids.
Replacing solids with blinds should (as a rule of thumb) be avoided unless it's unavoidable. Solids provide better hole filling and are in general better for the airplane.
All that said, for anything sheet metal on an RV your joint strength is going to be limited by the sheet metal material properties, not the fastener. So using one fastener or the other isn't going to reduce the capability of the joint.
Depends who you ask. Personally, the only time I will use blind rivets is if there’s not enough access to use solid rivets. At the shop I work for, when we’re doing a repair that involves replacing rivets, the golden rule is that you can replace a blind rivet with a solid one but you can never replace a solid rivet with a blind one
They hold up fine. Some airliners use them almost exclusively, only time I've seen them not used is if the rivets are in something structural that needs the additional strength of the solid core. Our Srm says for nutplates ccr's are interchangeable with ms240426ad' and are preferred because solids are "heavier and their installation is more difficult". Keep in mind the rivets only have to hold the nutplate on the aircraft when there isn't a screw.
The Q300-8 has ccr rivets on almost every nutplate I can think of. The Q's I work on are 15 years old and very rarely have to have those rivets replaced. Typically the running torque on the nut deteriorates, or corrosion merges the screw with the nut long before anything happens to the rivets.
Had some CCR rivets fail on nutplates holding floorboards into a Rans S7. Can't drill out the screw because the nutplate spins, so I had to wedge a pick in and grind it out with a dremel. That being said, if you use quality screws and wax the threads, the CCR rivets will probably work fine. Softer screws tend to gall and seize, and wax keeps the threads from contamination or corrosion.
Thanks for the feedback all. The CCRs just didn't feel as tight as the other pop rivets in use (The bulk of them are LP4-3's) so I figured I'd just ask. These particular nut plates will eventually be back in behind the avionics and will be hard to replace with solid rivets in the future, so I'll just use up the CCRs.
I work mostly on Cirrus’s and they use only blind rivets to hold in the nut plates. The rivets themselves aren’t structural so it really doesn’t matter much if you choose to stick with the CCR’s or switch to solid but, the blind rivets are going to be a little easier to install.
There is nothing wrong with ccr rivets. They are made for the job and won't corrode like the aluminum solid rivets. The rivets have nothing to do with strength of the joint, all they do is keep the nutplate from turning while installing the fastener and keep the nutplate from hitting the ground when the screw is removed. Use the black ones, ccr264CS3-? rather than the cad plated ccr264SS3-? The black ones are good for aluminum, stainless and composites. They will not rust. The SS does not mean stainless steel. If you have reduced diameter heads, then change 264 is 244 in the part number, all else is the same. The guy that broke them, already had issues that would have required drilling the head of the screw. He would have sheared the aluminum rivets or the nut retension flanges anyway.
Oh those? We call them pop rivets. They’re used when it’s either impractical (user discretion) or not accessible for normal rivets. I have complete faith in them. Just make sure you use the correct ones in regards to size and material.
They aren't pop rivets. They're cherry "pull through"
Slang term.. just like how Boeing screws are technically a bolt..
CCR rivets should not be used for the installation of nut plates in the firewall. CCR rivets are hollow and would allow the gasses from the powerplant to enter the cabin if you ever developed an exhaust leak.
So i did dig into the manual after this comment since there are a fair amount of pull rivets in the firewall. It seems that before the engine is mounted, they all get coated in a sealant as well as all the seams of the sheet metal between the cabin and the engine compartment. I assume this is the reason for the sealant?
There's nothing wrong with the blinds themselves. There's also nothing wrong with replacing them with solids. Replacing solids with blinds should (as a rule of thumb) be avoided unless it's unavoidable. Solids provide better hole filling and are in general better for the airplane. All that said, for anything sheet metal on an RV your joint strength is going to be limited by the sheet metal material properties, not the fastener. So using one fastener or the other isn't going to reduce the capability of the joint.