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Flush rivet sets

rightrudder

Well Known Member
What are you guys using for flush rivet sets? I've got a pretty large diameter set, and I'm having problems with it chattering, moving away from the head of the rivet and denting the skin a little on my horizontal stab. I know a lot of this is from inexperience, and my technique will improve over time.

My set doesn't have the rubber guard around the outside. Is this recommended? I'm taping up the set's face with blue painter's tape, and this seems to help a little, both in protecting the aluminum skin and reducing the "walking" tendency. Also, as a do more, I've developed a better trigger finger, so when the set does begin to move on the surface, I'm quicker to stop so the denting is minimized.

Thanks for any/ all input.
 
You may be using too high of an air pressure---------this causes unwanted bouncing.

Try setting a few rivets on some scrap, and using various air pressure settings.

Good luck.
 
I'm with Mike on this one. For me 40-45 psi feels good for 3/32 rivets and 60 for 1/8. I also go in 2-3 short bursts to keep the walking to a min.
 
The flush set shouldn't be bouncing around. Hold it firmly and like Mike said, you probably have too much air pressure. If this is a 3X gun, here is a chart of pressures to use.

My best suggestion is to buy some 3M heavy duty clear packing tape from your nearest Staples. Cut about a 3-4 inch piece. Fold over one edge so you have a tab to pick it off the surface you lay it on. Use this as "rivet tape" over the flush heads of the rivets you are bucking. It keeps the rivet in place, and protects the surface of the aluminum skin from the steel of the flush rivet set. This third hand makes it much easier to work the rivet gun and bucking bar together without worrying about knocking out the rivets as you shoot. As you have probably found out, sneaking up on the trigger gently gets the rivet shank to expand and hold on to the hole, then as you continue pulling the trigger the gun will produce the necessary hard hits to fully set the rivet.
 
I am with Mike and Carlos that the air may be too high.
I actually used more like 30# for the 3/32" rivets.
I also learned from a pro that to don't pull the trigger. It is like shooting a gun, you squeeze the trigger. Bring in the speed slowly like a variable speed drill. If the set is walking you are not holding it perpendicular.
 
Great, guys. Wonderful suggestions. I'll get some of that packing tape on the way home, and be extra-mindful about the pressures.
 
Interesting thread! I've encountered similar problems on my wing skins. I've had excellent results using a large diameter mushroom set with the rubber ring from Cleaveland, despite their reluctance to recommend it. I think maybe it just covers up poor technique and inexperience, though. The results are good. I think while waiting for my fuse kit I'll do some more practicing and see if I can't get a good solution. I need to add a good pressure regulator at the bench so maybe I can find the right pressure and the right technique.
 
it may take a few thousand rivets to learn this, but listen when you rivet. the rivet makes a low to high sound[sort of a screech] as it is squeezed. hitting it beyond the high pitch is just flattening it too much. also, too light of pressure will require hitting the rivet too many times, which can make it not seat perfectly.
 
I set my 3x rivet gun by sound and feel while hammering it against a price of wood. There's an EAA home builder video online that's pretty good info on flush riveting. I insert a rivet, cover it with a small post-it, then hold the gun firm and square against the skin before pulling the trigger. I got the best results when I consciously think that I'm going to hold the flush face firm and square to the skin before pulling the trigger, and continue holding it there until after I have let go of the trigger. Then lift. I think most my dings came from lifting the rivet gun off of the surface of the skin a split second before it completely stopped hammering, if that makes sense.
 
Great responses here. I think sometimes it's just a lapse of concentration when I release the pressure of the set against the skin at the end of a burst. I'm right-handed, but some situations require holding the gun in the left hand, which introduces another variable.

Oh well, none of the dings is too bad. They're like the mole on Marilyn Monroe's cheek…they add a little distinction to the beauty. But I'll strive to not add any more distinction, if possible!
 
The gauges that come with compressors and regulators vary widely, so an indicated pressure that works for one builder won't necessarily work in another builder's setup. Rivet on some scrap using varous diameters and lengths of rivets until you find what works for each one, and remember it or write it down. If you ever have to change out the pressure gauge, you'll want to again check the results on some scrap.

I use a small in-line regulator right at the gun, so it's convenient to adjust the pressure as requred, and it also lets me leave the compressor regulator set at 90psi for the drill, squeezer, or die grinder.

FP12082013A0002L.jpg
 
pressure

Once again pressure has nothing to do with it. We don't get to adjust the shop air pressure when on the job and most of us do not have a regulator on our guns.
It's all about technique. That and a decent gun with a feathering trigger.
 
Are you using the swivel head set? If not get one and that will stop the dents. for 3/32's I use like 35 PSI in short burst
 
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Are you using the swivel head set? If not get one and that will stop the dents. for 3/32's I use like 35 PSI in short burst

Yes, I'm using a swivel-head set, with a decent 3X gun whose trigger allows good modulation. I think I just need practice.

If I feel the dents are too unsightly, can a small amount of body filler be used later? I will work really hard to avoid dents in the future.
 
Flush rivets

+1 on the heavy packing tape. I actually use from one to four or more strips depending on the project. I put a cross hair on each with a a thick sharpie. Then when the mushroom set is placed against the work, I look at the set for the reflection of the cross hairs. It tells me I'm centered and square against the surface. With a bucking partner, I set a rivet, pull the tape, stick it on the skin for the next set and move to the next one. We can move pretty fast.
+1 on the regulator. I have two pigtails. One is labeled "high". One is labeled "low". I don't have to mess with pressure as much. The high one never changes. It's for the squeezer and the drill. The low one gets tweaked depending on rivet size.
My dents came because the gun was lifted before it stopped. :eek: Now I concentrate on leaving the gun in place for a second or two after my finger comes off.
I like a rivet to set in about 1 second burst. On my Sioux 3x and regulator, for a 3 rivet, it's about 22 psi but I've never actually measured the pressure with a super accurate gauge. I agree it's very relative.
 
It does take practice and playing with the settings on your particular setup. I would suggest getting some real thin scrap and setting at least 100 rivets before you go any further. Also make sure you keep the gun square with the work and that work cannot move at all. After you get a feel for it you will find that you can even hand the gun to someone else without any problem. For me it was all about dialing in air pressure and keeping the set firmly in place until the gun stopped. Enjoy perfecting the craft. You will, we all go threw this in the beginning.
 
The yardstore had a 1-3/4 swivel head that I really like a lot. I line it up well but if my hand moves a bit the swivel keeps things on target better.... Way fewer smilies, and it also helps set things on a curve better. they advertised is as a factory surplus special and may still have a few.
 
Again, fantastic input, everyone. I set some rivets last night, and the packing tape idea works great! It provides just a little bit of damping action and reduces the skating of the set--not to mention providing that third hand. Thanks, Bruce and Wirejock. :)

My technique is a ton better now. One rookie mistake that may have contributed to the dings was that the spring on the end of the rivet gun (that retains the set) wasn't fully screwed on; it was contacting the backside of the swivel and not allowing it to "float" properly.
 
New tip

Doug
I just tried a new trick and it worked well.
When you use packing tape it tends to get dirty on the sticky side making it difficult to see the rivet head. I mentioned making a cross hair target on the tape. The tape is placed so the cross hair is on the rivet head and it makes it easy to get the set on the center. The problem is the rivet set tends to wear it off . Today I put my cross hair on the sticky side. I finished off the top skins and the marks were still easy to see after all the rivets were done.
now if I could just hold that gun so I don't dent the skin!:eek:
 
I've tried a bunch of different tapes, and by far my favorite is electrical tape. It comes off without leaving residue, is cheap and doesn't tend to break like masking tape does.
 
Good stuff, Larry. Thx. I've been researching lightweight fillers so I can do a little touch-up on the dings in the paint-prep phase.

I hope to join the HS halves tonight with the forward spar….big step for me. :)

Electrical tape, huh? I've had such a good experience with the clear packing tape that I don't need anything on the face of the set. I'm glad it works for you.
 
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Dings

Doug
Don't mess with the dings. If you have it painted by a shop, they will fix them with the right filler compliant with the primer and paint.
If you decide to paint, ask the experts here first so you use a product that works with your product choice. You don't want a paint chip because it didn't stick to the repair.
I leave them so it's a constant reminder to be more careful!
 
Sounds good. It'll be painted by an automotive body shop that's only a couple hundred yards from my work. I've already talked to the foreman there and he's well versed in aluminum prep, compatible primers, etc. The worst dings are on the underside, too, so even if I leave them alone they won't be seen...unless I polevault over my nose gear, that is. :eek:

The left side is turning out great Thanks, VAFers! I should have the whole assembly riveted up by the weekend.
 
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