[wirejock]

Does anyone know if there is a tungsten bucking bar with a hole to use the squeezer dies?
Is it possible to drill mine?

I'm trying various methods (practicing on scrap) to rivet the ribs to the main wing spar. Practice rivets tend to roll just a bit. Vans calls for the manufactured head to be on the rib side. The rivets are 470s and there is no way to get a set in there square. I can almost get an offset set to work but it's not perfect. It seems to be caused by the set. I can hold the gun and set in a position that results in good heads but that position is not an option against the ribs.
Maybe my OCD is kicking in again but I want perfect shop heads.
I thought if I had a hole in the tungsten bar, I could use the squeezer die on the manufactured head and back rivet the spar side.

 

[SilverEagle2]

I am a little confused here. Are these the rivets attaching the main ribs to the main spar or the rear spar?

For the main spar, simply use a straight set in your rivet gun and your tungsten bar. The ribs will move out of the way some so you can get straight on the rivets with no issues (with the rear spar removed of course).

For the rear, you can use a squeezer for most, if not all of the rivets. I used a longeron yoke and got all of them.

 

[blueflyer]

I am a little confused here. Are these the rivets attaching the main ribs to the main spar or the rear spar?

For the main spar, simply use a straight set in your rivet gun and your tungsten bar. The ribs will move out of the way some so you can get straight on the rivets with no issues (with the rear spar removed of course).

For the rear, you can use a squeezer for most, if not all of the rivets. I used a longeron yoke and got all of them.

Ditto. I did the same thing, but I shot both the main and rear spar. Below is the tungsten bar I used from avery. I use it for everything....

 

[BSwayze]

Larry,

I'll show you a way to rivet those ribs to the main spar that produced flawless rivets, almost like back-riveting. Here's a link to my page where I describe how to do this. If you look at this page and the 2 pages that follow, you'll see how it works. Basically, the spar is supported on some blocks with the ribs sticking straight up, and the bucking bar is underneath. There's enough flexure in the spar to allow you to push down with the rivet gun and essentially backrivet those rivets. You'll love it! And Jason is right, you can gently push the rib to the side enough to get a straight rivet set in there. Obviously before the rear spar is clecoed on or riveted on.

http://www.europa.com/~swayze/RV-7A/Wings/20070804.html

Here are some pictures of the setup, but you should read the page to really see how it works. Too much to put in a post here.

Here are the results. Perfect rivets. I don't have a picture, unfortunately, but the shop heads on the other side are perfect as well:

Let me know if you have any questions.

 

[wirejock]

Thanks

I did say my OCD was kicking in right?
Silly me, the spar and ribs are clecoed together and mounted in the jig. DOH!
I will disassemble and back rivet as suggested. Feel kinda stupid now but very grateful.
Thanks for saving me from making a mess.

 

[BSwayze]

Larry,

I also wanted to comment on your idea of drilling your tungsten bucking bar to hold a die. I wouldn't try to drill tungsten, or risk damage to an expensive bucking bar. But I tried this, using an old hammer head. I did this when riveting the leading edge ribs to the spar, so I could try to get the manufactured heads on the rib flanges. The clearance is very close in there for riveting, and it's frustrating. So I tried this. Here's the creation I made:

Is this what you were thinking? My idea was to hold this thing inside the leading edge on the manufactured head of the rivet, while hammering the bucktail from below. My thinking was that this allows you to follow the standard protocol of using the manufactured head on the thinner material, and keep the shop head, or bucktail, on the thicker material side (the spar in this case).

In the end, it didn't work out so well. When you pull the trigger on the rivet gun, no matter how careful you are, this setup will bounce on and off the rivet, and the die will move slightly one way or the other, resulting in rivet heads with deep cuts in them from the edge of the die. I drilled out quite a few, just to get a few that were acceptable. In the end, I abandoned the idea and used some pop-rivets, like most builders do. Again, I'm talking about the leading edge ribs, not the main wing ribs.

Perhaps if you had a helper who could hold it very accurately so it doesn't move when you hammer the rivet, it might work. But I gave up. With no regrets.

Here's a link to my specific page that shows more about this, and more pictures:

http://www.europa.com/~swayze/RV-7A/Wings/20071227.html

If someone can figure out how to take this idea and run with it, it would be great for the group. But I gave it up and moved on. )

 

[wirejock]

Hammer head

That was exactly what I thought I needed. Looks like I might need it eventually. I swear I remember someone sold a tungsten bar with the hole in it just for this sort of thing.

 

[Ultra]

Tungsten bucking bars are far softer than you think..very easy to drill and file. and surprisingly, snap very easily...

 

[wirejock]

Thanks

Thanks Bruce!
I did it exactly the same and the results were perfect.
Left wing done and secured in the jig.
Right wing tomorrow.
That was one of the best tips ever.