Hi so im making these copper lanterns…have been forever …recently a decision was made to attach the cross bars with rivets…they had been soldered in the past but the joints kept failing…i habe had very limited success aircraft riveting these on…sometimes the rivets will take but even on the ones in which they take theyre not exactly forming an ideal shop head…and the failures terribly mangle the frame which i have spent months on…i need help with my technique in THE WORST WAY ASAP PLEASEEEE!!!
If no-one at the space has the knowledge you need, I can get you in contact with a friend of mine who does aircraft maintenance for a living. He lives in Florida, so probably better to find local help first.
If you’re using pop rivets, I’ve been looking into getting a pneumatic rivet gun. Maybe this is something the space could add? I’ve had similar troubles with the hand rivets, especially using a cheap hand gun from HF. @hon1nbo Do we have a pneumatic rivet gun in the shop?
No we do not. They are likely not regular pop rivets. Most aircraft rivets need to be bucked on the back side. @motopilot I believe has a lot of experience in it. He may be able to give you some pointers.
Solid rivets or flat rivets are bucked, generally in aviation and can be used on things like Airstreams. When doing decorative things, it can sometimes be impossible to get a bucking bar behind the metal that needs to be mechanically fastened. You can either design the piece so that you rivet the location prior to forming or you use a different style fastener.
In general, using tools that aren’t HF quality can produce very nice results. Using the tools you currently have access to, can you make the rivet do what you want on two pieces of flat stock repeatedly? If you’re using quality tools, then I would look at your process. If not, then it may not be possible to get a repeatable solution with the tools you currently use.
You can always try to buck a rivet by hand, but only a masochist would go this route.
Are some good and some bad? If so harder to isolate the problem and may be inconsistent technique. If they or almost all have the problem then it probably listed below.
Is it a copper rivet? If so the first thing I would do is anneal them to get them as soft as possible. They’ll work harden when you upset them, they will have work harden when they were formed as a rivet. If an Aluminum rivet what type/number? They come in different hardness. Is there cracking?
My first guess without looking is you probably have the incorrect Grip length and it is too long of a rivet and are having to upset more then you need.
Second, is the hole the correct size? If it is too big, it doesn’t take much, the rivet will move around making it hard to get a smooth upset. Upset should be about 1.5 times diameter of rivet shank.
Are you using the correct rivet set on the manufactured head? This mat will be a likely cause if deformed or cut on manufactured side.
What are you using for a bucking bar? Proper shape an weight helps a lot. Also is it being held firmly in place at the start and through out imparts? If it isn’t it will bounce around causing the head to malform. If the head is coming out “wedge shaped” then it is likely not being held perpendicular or bouncing.
Some other items:
I would strongly suggest you practice on some flat material until you isolate the rot cause of the problem. Then once you can consistently do it then go back to your project. I squeeze controls the process better with the right "bucking bar set-up you could squeeze them with the arbor press (the hydraulic press would probably take to long.
Hope there is answer is all of this.
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Not that I am aware of; I have seen members bring their own rivet guns when
working at the space.
-Jim
I think my issue is holes to big…drilled some holes smaller and it worked rather well…now im just trying to figure what to do with most my holes a little to big…they dont need to be aircraft or structural grade…just hold. To often they keep rolling and then when they take…the copper the brass bars are mounted on often gets mangled…
Rivet should just slide in or lightly touch when put into hole, no side play. You’ll need to get the right sized drill for it.
Is the “mangling” on the upset or preformed head? Radiused or flat surface?
If on the preform/manufactured head I’d say wrong set size, if damage is around the head then the set is likely too big and deep so hitting outside. If set were too small the head would be damaged.
If the upset side, my guess bucking bar bouncing around and hitting material, wrong shape/size (If on and inside radius, make sure it isn’t too wide or you are over-driving the rivet. Again make sure correct grip size is being used.
You may try some softer rivets so they drive easier - they will still work harden when driven Something like this:
https://bylerrivet.com/products/items-list.aspx?cat=425
You might also consider potential galvanic corrosion issues with riveting copper with a dissimilar metal.
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I have all the riveting tools and could help you sometime. A squeezer might be just the ticket for what you’re trying to do.
Do you have photos?
arent brass and copper like 95% same composition i believe. though certainly galvanic corrosion is a concern with dissimilarity. i couldnt imagine it being a problem in this case.
I didn’t know if you were going to use aluminum rivets. It’s an issue with aluminum rivets.
i have tried on just copper scrap and the results are terrible. id say my problem definitely is holes to big…the rivet just tumbles. the ones that have “TAKEN” will hold for this but would certainly not be passable as proper shop heads. at first i was definitely using the wrong set. most of the successes have been when i did preheat the rivets. The rivets in the proper hole size fit and form with ease. The solution at this point is to replace messed up bars and to patch holes to large with a soldered in copper patch on the back side and redrill to proper size. its a pain but theres no way around this from where im standing. yes all of this has been very helpful.
i had thought about a squeezer but its a rather difficult position for such a large tool unless it is a vertical squeezer like one of the long ones where the squeeze throat is perpendicular to the body of the tool…if you have one of those then yesss.
absolutely. thankyou for your concern as galvanic corrosion is a nasty little silent demon thats easy to forget about.
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Brass is primarily Copper and Zinc
Bronze is primarily Copper and Tin
I think itd be wise to take you up on your offer…the air hammer riveter keeps mangling… definitely not user error 
I’ll be there on Sunday during laser maintenance