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Riveting success?

All,

I need a critique on my back riveting...scrap it or build on?

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Thanks
 
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critique

Patrick
Welcome.
Absolutely horrible! I would trash it.:D

Seriously, I don't see why you would need to ask. They look fine. Maybe just a hair over-driven but It might just be the pic.
Get a set of rivet gauges or look up the min/max and drill a piece of scrap to check shop heads. They are just a hair pushed over but not worth drilling. Probably because the rivet set is not perpendicular to the shop head. Most of us have a flat ground on the set to allow it to get close to the flange.
Nice work. Build on!

Are you using Sherwin Williams P60G primer? If so, I would go much lighter.
 
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Larry,

Appreciate the quick reply and confirmation on the rivets. They are a little over-driven based upon the Avery gauge.

I'm using the SEM rattle can at the moment. Thinking of switching to Duplicolor purely because of cost. I will probably switch to my spray gun on the wings, still building confidence with it and trying to find a good place to build a small booth. Competing with space in the garage.

Pat
 
rivets

As they are stiffeners, build on. I still think they look fine.
Look up the min/max dimensions for shop heads and shoot for something in between. No need to hit the max every time.Make a min gauge so you know how small is too small.
It won't take long before you won't need a gauge.
 
Look up the min/max dimensions for shop heads and shoot for something in between. No need to hit the max every time.Make a min gauge so you know how small is too small.

This is a good suggestion. One of the first things I did was make a go / no-go gauge using the actual min and max sizes and I use it every day.
 
Next time you rent or ride in a certificated aluminum airplane, take a look at the accessible rivets. For extra fun bring your rivet gauge. ;-) These planes are built and maintained by professionals, but after looking at them as closely as you look at your own work, you'll feel much more confident about the rivets you set!
 
Not to hijack the thread.....

What are the min/max shop head sizes for a -3 or -4 rivet? I have the single hole go/no go gauges for each but always wondered which is better, slightly over or slightly under.

Would love to make a min max gauge if I knew the diameters.


E
 
They look ok, but you wanted some critique, so here goes.

When you backrivet, be sure to hold the set perpendicular to the work. It's hard to tell from the photo, but it looks to me like some of the rivets are smushed to one side a little, indicating the back rivet set was slightly angled when you squeezed the trigger.
 
Min max

Look at the specs. There is no max on the diam. Of
the shop head,only min. However, there is a min and
a max height of the shop head. Use a dial caliper to measure.
The standard no go gauges are set up with the mean. And do not
represent max or min.
 
Plus 1, and some suggestions....

They look ok, but you wanted some critique, so here goes.

When you back rivet, be sure to hold the set perpendicular to the work. It's hard to tell from the photo, but it looks to me like some of the rivets are smushed to one side a little, indicating the back rivet set was slightly angled when you squeezed the trigger.

First, they look fine and as long as the manufactured heads look good you should build on IMHO.

Some do look a little canted to one side, and I had the same problem. If memory serves, I tried to correct this by either applying a bit more firm pressure with my thumb and fingers holding the back rivet frame to ensure that a) it was flush and therefore perpendicular to the riveting surface and the rivet shank, and b) that the back rivet set would not move when I started riveting.

I may have even applied some pressure with my other hand on the top of the rivet gun instead of holding the back rivet set, but I think I actually did the former method by holding the rivet set with my left hand and the gun with my right.

Then there is the question of which back rivet set you are using - i.e. from which tool manufacturer? One company produces a rather large diameter one that many others have reported having problems with while trying to center the back rivet set over the rivet shank. This is because the diameter of the frame is too large, and contacts the vertical part of the stiffener. Other manufacturers make a slightly smaller diameter one that fits better on the stiffener, and therefore also centers better over the rivet shank, reducing the tendancy to cant the rivet to one side or the other.

Perhaps the most accurate reason I found for the slight canting of the shop heads was that my arms and hands were not kept close to my body and to the centerline of the rivet gun. In other words, every time I rivet I try to place my hands, arms and eyes in a position that is as close to the centerline of the rivet gun as possible. I think when you start getting your arms further away from your body that there is a tendency for the gun to lean back toward your body when you start riveting, and this is the reason why the canting occurs.

Keep two hands on the gun/rivet set-don't try to rivet with one hand and hold the skin open with the other - ask me how I know! Go slow with the rivet gun, making sure that the back rivet stays perpendicular and does not slide. - Easier said than done sometimes, but those are my suggestions.
 
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Nice Work

Patrick,
Your riveting looks great... as stated in the Van's construction..
buck them half the diameter of the rivet and the shop head should be 1-1/2 times the diameter. you can check this with the rod end of a micrometer until you get comfortable. If you measure every rivet with a guage I'll see your plane in a decade. Yours look great..... keep building...

a long time sheet metal guy told me that if you take your finger and press it over the shop head that is correct a few times... you'll almost know when a good head is formed..Again. you can measure a few with a micrometer and be extremely accurate until your know what is right. Every now and then in the build I would just double check to make sure I was still accurate with a micrometer.

There are several places during your build you can not get a guage into and finger press method works pretty well. All your rivets on the second set of skins for the wings you'll hardly be able to reach... but your finger will be able to press hard enough to basically judge how they are. Then when you get done with a section. Take a telescoping mirror and flashlight and remember what Van's stated and look at all your rivets... you will probably have to reset a couple but generally you'll do fine.

Don't worry, after a few thousand rivets... and drilling out a few... you'll get pretty good. And you'll get some that will cause you to take a break and come back. Remember it is always better to drill out a rivet head with an under size drill first... don't be afraid to angle the drill to get the bit centered in a head of a rivet. only drill the head out and use a punch to drive out the body. It will keep you from elongating a hole.

All the above is my honest opinion and what I did, I had a couplel sheet metal who retired from Dobbins AFB riveters look over my plane... I told them don't be nice.. If you see something let me know so I can correct it. Get your work inspected by an EAA tech inspector a couple of times during the build. Most of these fellows are pretty good and will make great suggestions.

Jack
 
Nice job Patrick! I want to know how you managed to back rivet all those stiffeners without putting any visible marring on the primer around the rivets. It looks fine to me, but maybe go a little lighter on the primer. If there are any that are not perfectly square, or slightly overdriven, don't worry about it. Make small adjustments and build on. If you put every driven rivet under a micro scope and offer it up to the scrutiny of this gallery of experts (and we are all experts), you'll be a gray beard before you get to enjoy the flying part.

It's good to get oversight when you start, and you're doing that now, so - way to go. You're doing a great job. Head the advice here, and in a short time you'll be an expert too, and your eye will be as good as anybody's. I look forward to seeing your finished airplane.
 
Looks good with the minor critiques and possible corrections already given. Here is a little trick you can use to develop your skills at recognizing properly set rivets, especially those that will be blind to you, when you start closing things up.
Measure your shop heads and establish what you know is within tolerance. Set some rivets in some scrap on both sides of the tolerance, and some right in the middle. Use your thumb or forefinger and press down on the shop head. It will leave a very well defined depression. Measure that. After a little while, you will be able to recognize a properly set rivet by how it feels when you press you thumb or end of finger on it. You will be amazed at how accurate you can become simply by how it feels when you press on it.
You will also be able to visually learn how they should look over time.

I never used a rivet gage. I measured them until I was comfortable with sight and feel. Experience will take it from there.
Keep in mind, for most structures in an RV, it is not even recommended to remove an improperly set rivet unless two are side by side or there are more than one in every four or five. That is a lot of poorly set rivets that will still have little or no affect on overall strength of the airframe.
Now, that said, we are picky animals us RV builders. Most of us just don't sleep well unless we remove it and do it over.

None of yours are even close to being a concern. Nice job.
 
Thank you!

Everyone,

I really appreciate all the feedback provided. I know its been said many times, but this is such an awesome forum!

This is my second run on the rudder skin. The first is now training material after I got into a groove and the back rivet plate was not longer where I thought it was. As Mike and Bryan pointed out I was a little concerned that some of the rivets were a little over driven and smushed over. Advice taken on board to keep the gun in tight to the body and perpendicular to the work.

I'll have to adjust my pattern while painting. I think I may be moving a little too slow putting a little more paint down than I need.

Dave - photo below of the other side of the work. I think it looks good, no proud rivets.
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Again I really appreciate everyone taking the time to reply. I'm sure I will continue to second guess some...maybe all...of my work until I get really comfortable. Until then I know I can rely on members of this forum to keep me grounded.

Pat
 
I had to lean the gun a little towards the upward stiffener flange in order to get a back rivet that wasn't pushed over.

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Just learning here also, but we were experiencing the same problem here of the rivets being not perfectly round to the hole when back riveting. Did some research on it and found that the work bench we use (made for wood working) was not solid enough and with the small back riveting plate thickness of ?? we have it caused deflection or bouncing. We proved this by laying carpet on the concrete with the back riveting plate between the carpet and then back riveting the stiffeners. They came out perfect on the floor.
 
Looks good to me!

I replaced my entire elevator skins since I was paranoid about my heads bent over a little bit. I also had problems since it always seemed to bend when I was using the bucking plate so I used a buck bar. That made it even worse since it wasn't as flat as I wanted. Finally replaced the skins and met with a local builder that showed me some tricks. Lower the pressure on the riverter way down to about 37psi rather than 90psi. Sure, they may still bend over a little bit, but noting to stress over!

I'll share my ugliness here -
http://www.mykitlog.com/users/displ...&project=2260&category=9074&log=179719&row=51

and...
http://www.mykitlog.com/users/displ...&project=2260&category=9074&log=179720&row=50

and some more...
http://www.mykitlog.com/users/displ...&project=2260&category=9074&log=179723&row=47

Anyway, you see my problem! I replaced it re-built that. Only about $65 for each skin and a few hours setback. Yours looks great!

Tom
RV7A
98% done with empennage
Currently waiting for airport house sale to close to keep building!
:)
 
pressure

Tom
I did that too but not on my Lucy. Before getting some excellent mentoring, I tried setting rivets with my gun at 90 psi. Holy cow!
 
I learned the hard way about PSI starting out. I was like what? Adjust the air pressure? O, that's better!
 
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