SonexBuilders.net

Just wondering how may builders have chosen to go with flush rivets on the exterior skins. I have decided to, and found that the inventory sheet sent with my tail kit doesn't match the rivets required to complete certain areas. Leading me to believe not many people have purchased the flush rivet option.

I went for the bumpy look :D Call me lazy but have you seen how many holes there are in these planes. :o

The stock rivets are "low profile" enough they don't bother me. I don't mind the look :)

I got a chance to see a sonex that had been completely flush riveted recently. I don't think it looked all that much different. Unless you are going to fill each rivet and paint the plane you still end up with a hole where the rivet stem pulls through for each rivet and can also see the outline of the head against the sheetmetal. This made the rivets just as visable as the regular ones. It actually took me a few minutes before I even relized that the plane I was looking at was flush riveted. I just don't really understand the reasoning behind doing all that extra work for very little gain.

Keith

One of the reasons I like the flush rivets, is the strength of the two dimples once they are riveted together. I guess part of it is the RV builder in me. If you have the right tools its not that bad. I have a dimpling table that you slide the skin around on, which has a two foot reach, and a pneumatic C -squeeze for the frames. Those two tools make it a lot faster, and easier. In the end it's just personal preference, as long as you

I'm using the std rivets, build time is an important factor for me, I'd like to fly my plane some time in the future too.
If I were to go with flush rivets, I'd go all the way and use solid rivets where possible.

I went all in and used solid rivets where possible. I do plan on painting and just prefer that smooth look. I will be the first to admit it is more work.
Joe/Onex0041

Question for you flush rivet guys..

How did you ever get those dang CCC-42 mandrels to not break off too high? I experienced the dreaded protruding mandrel heartache early on with the random places they are called out on the tail, as a lot of people do. I did not want to have to deal with them over the entire leading edge of my wing, so i read all the advice i could find on line, and did my own series of experiments with different dimple dies, dril bit sizes, sequences.. etc. What gave me the best results in my own experimentation was to final drill to a #32, and then use the Sonex Simple Dimple Dies with BOTH sheets at the same time. However i just riveted on my first leading edge the other day and probably half of them still broke off to high. I am extremely frustrated and would love to find a better solution. What is the secret?

All I can do is tell you what worked for me,and this was from Jeremy. Air pressure the lowest you can get away with (I use 40lbs)
and pre drill one size smaller first. For non dimpled areas that was a #31 followed by #30 and I can honestly say I have not had a ccp 42 break proud since.Will this method also work for the dimpled areas I have no idea. Jeremy said if the hole is sloppy ie not round then these rivets will sometimes cause a problem breaking proud.By up-drilling twice you get a perfect round hole.
Having to up drill twice is a pain in the butt and I have since gone back to just drilling #30 and grinding down the 1 in 10 to 20 that break proud .I figure it takes a lot less time then drilling everything twice ,of course that depends on how many break proud.
This really should not be an issue and I suspect the bean counters maybe got carried away ;)
Mike

142YX wrote:Question for you flush rivet guys..

How did you ever get those dang CCC-42 mandrels to not break off too high? I experienced the dreaded protruding mandrel heartache early on with the random places they are called out on the tail, as a lot of people do. I did not want to have to deal with them over the entire leading edge of my wing, so i read all the advice i could find on line, and did my own series of experiments with different dimple dies, dril bit sizes, sequences.. etc. What gave me the best results in my own experimentation was to final drill to a #32, and then use the Sonex Simple Dimple Dies with BOTH sheets at the same time. However i just riveted on my first leading edge the other day and probably half of them still broke off to high. I am extremely frustrated and would love to find a better solution. What is the secret?

I agree with Mike,

Making sure the holes are a tight fit after dimpling is key here, if the hole is to wide, your rivet will contract more than it's supposed to and that's when it will appear the mandrel breaks in the wrong location, outside of the rivet (but the problem is actually that it's been allowed to be pulled out of the rivet too far, it is breaking where it's supposed to)

I also experienced the problem initially but after a experimenting with drill bit sizes before dimpling to find the bit that would give me the exact 1/8th diameter after dimpling, I had no more problem.
a #32 is what I came up with.