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1:1 Scale

Well Known Member
I was planning on spending the whole day today countersinking the spars and riveting my leading edges in place, but the first three attempts at setting rivets through the spar and W-408-1L (inboard most rib) have got my blood pressure up a bit too high for a "recreational activity":(

I started with grinding down my offset rivet set:
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I really don't want to take anymore off of it for fear of getting a sharper edge on it.

These are the rivets that my wife and I have set so far. Not pretty:
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Even if i wanted to drill them out, I'm not sure if I could. I don't have a 12" drill bit, but I'm not sure if that would even be the best tool for the job:confused:

Any input is welcome! I'm going to go eat some ice cream out of the carton;)
 
Let me guess, you seemed to beat on them for ever? Believe it or not, my strong suggestion is much higher air pressure at the gun. The offset rivet set consumes a lot of the energy, along with longer rivets in the relatively thick doubler on the spar. All that adds up to needing higher pressure, and hold the set and gun with two hands (partner bucking). Also, believe it or not, it is sometimes easier to drive such rivets with a long straight set that isn't perfectly aligned than the offset set. The longer the set, the higher the pressure you'll need. For reference, I wouldn't be afraid of 80psi on a 3x gun where the set is long, rivets are long, and material is thick. Been there, done that, twice now.
 
We beat on them longer than I wanted to, for sure. It's a 2X gun with the pressure regulator on the compressor set at 120psi. I think one of the big issues is there isn't enough pressure being placed on one end of the rivet (don't make me put it in print;) ). I've never been fond of the offset set, either.
 
1:1 Scale said:
We beat on them longer than I wanted to, for sure. It's a 2X gun with the pressure regulator on the compressor set at 120psi. I think one of the big issues is there isn't enough pressure being placed on one end of the rivet (don't make me put it in print;) ). I've never been fond of the offset set, either.
Click to expand...

2X gun is a lot of the problem.
It does not have enough ommf on an AN4 rivet in structure this solid.
If a rivet doesn't set with-in the count of thousand one, thousand two, thousand three; it is going hard and will not set with any size gun.

See if you can borrow a 3X gun to try. Another help is to use a small piece of duct tape wrapped around the spring and rivet set. This will help keep the set from rotating in the gun, but you can still rotate the spring to orient the set to what ever position you need it.

One other thing...it looks like an old rivet set...surplus maybe? Is it possible that it is actually for AN5 sized rivets? They can be hard to distinguish, it looks kind of large on the end. If it is #5, it would also be causing some of the problem visible in the photo.
 
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12" Drill Bits

I'd recommend you get some 12" bits...you'll use them during the build.

Sizes #40, #30 are needed. Get the good cobalt ones.

You can drill standard rivets out on the spar using a 12" long #40 bit. Use an electric drill and take your time to make sure you're aimed at the center. Once you drill slightly past the head of the rivet, change over to the 12" long #30 bit and drill just deep enough to pop off the rivet head. Then switch back to the #40 and finish drilling through the rivet shank. Doing it this way takes a little longer but you run less risk of messing up the hole. Once you've drilled the center out of the shank you can pop it out using a 1/8" punch. Practice on some scrap before you try this on your spar-you'll be able to develop this skill in no time.

I'd also recommend some "Snap Soc" rivet set caps from Brown or Avery. These are plastic caps that fit over the rivet set. You should only need the 1/8" size and a bag will last a long time. They really help prevent Smileys-see:

http://www.averytools.com/p-884-snap-socrivet-set-caps.aspx

As an alternative you can use a small piece of duct tape on the rivet set, but I much prefer the Snap Socs.

Enjoy the ice cream and good luck,
Mike
 
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I agree with both comments. The 1/8" rivets are generally much harder to set than the 3/32 ... especially the longer rivets. I had to increase the pressure to 90# on my 3X gun to get some of the longer ones set.
 
As Scott says...

"hold the set and gun with two hands (partner bucking)"

This really does make a difference - a lot of builders are reluctant to actually hold the set while bucking, but it helps with these offset sets...

If you don't, the set starts to rotate and everything goes to h*&^ quickly, and smileys grow...:mad:
 
Agreed on the 3X gun as well - that will make a big difference. I run 40-50 psi on a 2X for -3 rivets and 80-90 psi on a 3X for -4 rivets with good results. You want to form the shop head on the rivet with a minimum number of blows before the material work hardens - after that happens, you're not going to move the metal no matter how long you beat on it.
 
Thaks everyone!

I've ordered up some 12" drill bits and a 3/32" and 1/8" punch, and have a friend that has a "2X gun with a 3X piston" that he really likes and is going to send me to try. I'll also try the duct tape in the tip and around the spring. I had tried holding the set on the second and third rivets, and they were getting better, but I think we just worked on them too much in the end.

Scott, I bought the set second hand, but it has "1/8" 470" stamped on it, so I'm pretty sure it's the right set:)

I guess I'll dimple ribs and prep the top skins for riveting until the tools get here:) Sucks waking up at 2AM to the thought of "rivet defeat" though:D
 
Use Blind Rivets?

For my RV-9, after looking at the contortions that would be required to drive those rivets attaching the LE to the spar, I asked Van's whether blind rivets can be used. Here is their answer:

"It is acceptable to attach the leading edge ribs to the spar with LP4-3 or LP4-
4 blind rivets. Be sure to use the proper grip length rivet for the material
thickness."

...Joe
 
First real frustration

Kelly, I had the same problem and same frustration. For me part of the solution was Blue Bell coffee flavor.
2 of my middle ribs on the first wing looked just like yours. Repeated attempts kept comming out the same way.
I called Vans and asked about using nut plates on the second wing's rib flanges and screws through the spar. They were ok with it as long as I was ok with the extra weight(2 rivits, nutplate, screw and washer per 1/8" rivit hole). Wish I had done it sooner instead of fretting over it for a week.
Vic
RV-8 Wings and tail done. Working on Fuse.
 
az_gila said:
"hold the set and gun with two hands (partner bucking)"

This really does make a difference - a lot of builders are reluctant to actually hold the set while bucking, but it helps with these offset sets...

If you don't, the set starts to rotate and everything goes to h*&^ quickly, and smileys grow...:mad:
Click to expand...

Which is why, when working single handed with the offset set, duct tape around it is really useful to stop the set from rotating. Mind you, I only do this if I absolutely must; as long as I can wait for assistance, I'll wait so I can then use both hands. I hate that offset set. Stupid thing.
 
Two hands

I've had very little help. But where it really made a difference was on these -4's. Gotta hold the set in one hand, gun in the other. If you need to, get a different helper, politically correctly, of course. The Avery set protectors worked for me too, but I suspect a lot of that is mental; they are a bigger help when there is a inexperienced helper on the gun.

I do differ with some gun comments. The rivet forming gets done by the bucking bar. My tungsten bucking bar was rec'd about halfway through these, and it made a world of difference. I haven't has a place where a 2x at 60 psi wasn't sufficient, but I've also got a regulated header tank (10 gal) and only use 10' of hose to my tools. This stuff matters.

I also have some cherry structural rivets in some of these holes, generally closest to the spar flange, out of frustration. And some smiley ones. And a rib doink or two. An extra dab of primer and it all disappears. You're in a lot of company.

Build on!

Rick
 
Ah yes, remember those rivets well. I had tendonitis in my riveting arm for months after that. Riveting and reaching don't mix...
 
I bucked those while my wife drove them in. We used a 10" extension in my rivet gun. We found that keeping the set as straight as possible and using plenty of force would keep the rivets looking nice.

Holding the set in place never hurts either. It took us a while to get over the fear of touching the set while the rivet gun was pounding.
 
Geico266 said:
Get your hands on a 3X gun for the larger rivets.
Click to expand...

Ditto what Larry said.

or even my favorite - a 4x....you can always turn the air pressure down on the bigger guns. I think you'll find that most people who've shot lots of rivets prefer a 3 or 4 - not I many I know prefer a 2.

Lots of other good advice as well. Mel makes a good point about holding the offset sets - almost a must do.

My 2 cents as usual.

Cheers,
Stein
 
1:1 Scale said:
I've ordered up some 12" drill bits and a 3/32" and 1/8" punch, and have a friend that has a "2X gun with a 3X piston" that he really likes and is going to send me to try. I'll also try the duct tape in the tip and around the spring. I had tried holding the set on the second and third rivets, and they were getting better, but I think we just worked on them too much in the end.

Scott, I bought the set second hand, but it has "1/8" 470" stamped on it, so I'm pretty sure it's the right set:)

I guess I'll dimple ribs and prep the top skins for riveting until the tools get here:) Sucks waking up at 2AM to the thought of "rivet defeat" though:D
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Hey Kelly,

I've got a 3x gun, 12 '' bits and snap socs. give me a call if you want to use them, i've been busy building some barns. I'll be out of town in november.

danny (bend)

i've also got the tungsten bars if you want to use them
 
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