[N546RV]

I suspect I know the popular answer to this one, but I'm asking anyway. My hand squezer has a pretty shallow yoke, so while I can easily get to the two "end" rivets, the center one is a different matter. I hit this wall tonight, and after standing around considering the situation, I went after the center rivet using the rivet gun with a single offset set and a bucking bar that appeared to be made for just such a situation. However, even after very carefully positioning everything and making a short test burst with the gun, the shop head was already starting to lean.

So now I have to get that thing drilled out and reevaluate how to rivet here. I'm thinking the thing to do is to go ahead and invest in a better squeezer with a replaceable yoke. As much as I want to keep up the momentum on this thing, I'm not very faithful that trying to use the gun on this rivet again is going to be any better.

So what did everyone here do? Hand/pneumatic squeezer with 3/4" yoke? Did anyone successfully buck this thing?

Thanks.

 

[tkatc]

Can't help you but I'll be watching for the replies and hopefully learning from your build. The VS is the next step for me...if I ever get through the HS.

 

[bruceh]

Get some scrap and practice your riveting/bucking. I got better and better everytime I would rivet. Some rivets look challenging, or down right impossible to buck, but it is technique/skill/experience that will over come it. Check your air pressure on the gun. It takes more psi than you think with the offset rivet set vs. the flush set. Once you get 5 or 6 good rivets on the practice material, have a go at the VS.
Every time I botched a rivet (pretty much guaranteed at least 1 rivet gets drilled out at every session), it boiled down to technique (getting it securely clamped down) or air pressure being wrong (too little or too much). I've used this air pressure cheat sheet with success.

 

[N546RV]

Get some scrap and practice your riveting/bucking. I got better and better everytime I would rivet. Some rivets look challenging, or down right impossible to buck, but it is technique/skill/experience that will over come it. Check your air pressure on the gun. It takes more psi than you think with the offset rivet set vs. the flush set. Once you get 5 or 6 good rivets on the practice material, have a go at the VS.
Every time I botched a rivet (pretty much guaranteed at least 1 rivet gets drilled out at every session), it boiled down to technique (getting it securely clamped down) or air pressure being wrong (too little or too much). I've used this air pressure cheat sheet with success.

I'm pretty consistent and good bucking rivets out in the open. The constraints in this spot just make it difficult to get the bucking bar in and hold it straight. The angle at which the ribs attach to the forward spar also make it tougher to properly judge the right angle for the bucking bar; I suspect that's what caused my problems. I could probably go back and, with more care, buck this rivet OK, but I'm hesitant to tempt fate. More likely, I'll be ordering a better squeezer in the near future.

I used to joke that the mark of a successful project was having to buy new tools. Using that yardstick, I could quit the RV project today and it would still be my most successful project by a long shot!

 

[Shockwave]

Mine has 5 rivets there.

I botched one of the holes a couple of times. I took it over to my tech counselor and with his help we got it bucked acceptably. The hole was getting bad by that point, so we drilled in between the middle and end rivets and set another without issue. We decided to make it look pretty (symmetrical) and put in another rivet on the other side.

Yes it can be bucked, and yes it is a tricky one. I think the secret was to basically bend the rest of the rib out of the way and then bend it back when we were done.

 

[Shockwave]

I used to joke that the mark of a successful project was having to buy new tools. Using that yardstick, I could quit the RV project today and it would still be my most successful project by a long shot!

LOL! I feel your pain. I thought I'd put together my tools as I went. Instead I found that nearly every tool was required on the empennage so my tool shopping never really got a break. I'm still trying to justify an alligator squeezer.

 

[rzbill]

Rivet gun, straight set (or maybe an angle set if you want) and any one of a myriad of angle faced bucking bars such as:

Bucking bar

Applied per Bruce's notes.

It is my opinion that your tool dollar is better spent on variants of sets, jaws, bucks and other hand tools than the air powered riveters. The air power won't compensate for not having the right geometry to access the rivet.

There are exceptions to this generality of course but I can say that I never "figure 8'ed" a hole or damaged a fingertip with a manual squeezer.

 

[Flyin'Bryan]

Great Advice from Bruce

Get some scrap and practice your riveting/bucking. I got better and better everytime I would rivet. Some rivets look challenging, or down right impossible to buck, but it is technique/skill/experience that will over come it. Check your air pressure on the gun. It takes more psi than you think with the offset rivet set vs. the flush set. Once you get 5 or 6 good rivets on the practice material, have a go at the VS.
Every time I botched a rivet (pretty much guaranteed at least 1 rivet gets drilled out at every session), it boiled down to technique (getting it securely clamped down) or air pressure being wrong (too little or too much). I've used this air pressure cheat sheet with success.

Phil, I checked my blog last night after seeing your post, and wouldn't you know it, the one part of the VS I did not seem to document very well is the area you are referring to. I am attaching two links - one that that discusses the rib attachment to the rear spar of the VS, as the concepts are the same, except that the forward spar is another case where you are mashing 3 separate parts together (VS704, VS702, and VS705). The second link shows one of my clamping methods.

Bruce has some very wise advice here - clamp the work, setup practice pieces with the same angles if possible, and make air pressure adjustments, etc.

As for the joint for the forward spar/rib attachments - I can tell you that I had problems as well, and I remember drilling out one rivet that became rather nastily folded over. I think I tried to squeeze those rivets with the air squeezer if I remember correctly. If I had it to do over again I would probably buck the rivets as described below.

So my best advice I guess is:
-clamp and secure the work

-regardless of the riveting method you choose, put the manufactured heads of the rivets on which ever side of the assembly gives you more clearance for the rivet gun and rivet set or squeezer.

-use a double offset rivet set and the rivet gun with air pressure turned down a bit

- Check the length of your rivet shaft. Vans has a nasty habit of providing rivet callouts in certain places that leave the rivet shaft a bit too long. if you find that this is the case, get a longer rivet and cut it down to the correct size. I did this in several areas fo the elevators while employing the same rivet techniques mentioned above, and I was glad I did.

- tap the rivets a couple of times to check the rivet shaft for signs of folding to one side or another, and adjust the bucking bar to compensate

-forget about using an air squeezer unless you can successfully bend the rib out of the way without forcing the rib flange to separate from the forward spar too much. In my experience there is just too much movement that occurs when the ram shoots up when you hit the trigger, and the position of the yoke and the sets can change in that split second, causing problems.

- or, if you wish to try to squeeze the rivets, use a hand squeezer so you can take your time and get the yoke into just the right position. Then you can perform partial squeezes and check the progress of the rivet

-If squeezing, determine the best flat rivet set to use for the shop head to clear the flanges.

- If bucking - use a tungsten bucking bar with an angle end on it to keep the bar away from the rest of the framework as much as possible. Tape up the bar to prevent dings on any other surfaces

- In the cup of the double offset rivet set, put some masking tape inside it or over the top of the rivet head to prevent smilies on or near the rivet

- Clamp the framework into position so that gravity can help you and not work against you (rivet set and gun facing down if possible, or side to side for visiblity of both sides)

- Try setting the rivet in the middle first - this is the hard one. Then you can work out to either end for the remaining easier to reach rivets on the end, while the center rivet helps hold things in place.

I realize this is a mouthful, but there you have it.

http://bryansrv8project.blogspot.com/2011/01/attaching-rear-spar.html

http://bryansrv8project.blogspot.com/2011/01/good-rules-to-follow.html

Click on the pics to get a larger more detailed image.

Git er done and KPR!

 

[N546RV]

Thanks for all the info, Bryan. I took another useful bit of information from reading your first blog post that might have helped me as well. You see, when I was first considering how to approach this, I knew that I could get the hand squeezer on the two end rivets without much trouble, and that the center rivet would be the tough one. As is sort of my custom, I decided to attack the tough one first.

My first thought was to have my co-builder/better half pull the nose rib out of the way, since that's where the biggest clearance issue exists. (due to the acute angle between the front spar and the bottom of the rib) But when i tried pulling it out of the way, the rib flange almost immediately separated from the flange. Riveting with that separation seemed like a true setup for disaster, so I abandoned that idea.

The important bit I got from your blog concerns the difference in clamping power between clecos and rivets. Perhaps if I'd set the two end rivets first, I then would have been better able to pull the nose rib out of the way before attacking the center rivet.

In any case, I think I'm going to cough up for a Main Squeeze in the next day or so. Ny hands hurt like heck after a session of squeezing the rivets on the rear v-stab spar...and my girlfriend is completely unable to squeeze -4 rivets with my cheapo squeezer. I think with a 3" yoke, I can reach that center rivet, but in the meantime, I may hit the edge rivets and see if that helps me get a better shot at bucking the center one. If I don't feel comfortable, I'll wait for the new squeezer.

 

[Flyin'Bryan]

Always more than one way to skin a cat, or a skin.....

...or a rib, or a spar, etc. Definitely if you have a pair of extra helping hands that is ALWAYS a huge plus. Sounds like you have a plan in mind, and if you just take your time with it I think it will work out fine.

If it makes you feel any better, I think the one rivet that I messed up had to be drilled out and replaced. In the process I enlarged the hole to the point where I needed to use a -4 rivet that was one size longer to ensure that I filled it. Tense moments for sure while I mashed it down, but it seemed to work out OK.

The -4 rivets definitely are no fun to squeeze by hand. Sorry to ehar that you squeezed all the rear spar rivets (ouch!). I bucked all of mine for all of the rear spars, and they came out great. Perhaps a compromise for the forward spar assembly would be to start it with the hand squeezer just far enough until it secures the parts in place, and finish it with the air squeezer or just buck it the rest of the way.

I guess I have resorted to a "resist the temptation" approach when it comes to self doubts while attempting to tackle the hard jobs. What I mean by that is that if it does not look right or feel right, then just don't do it. Think about it some more, or try something new like retooling, repositioning, reclamping, etc., and when it feels comfortable and looks right (won't ding other parts or won't cause a rivet to bend the wrong way), it usually comes out right. Sounds like you are in that same frame of mind, and that is a good thing.

Be sure to post a pic or two when you get it worked out.

 

[GAHco]

Handy little things.

If I remember correctly it is about the same on the Six.
I reamed the holes to 5/32n's and installed Hi-loks, pretty easy

 

[SilverEagle2]

As I recall, I used my standard yoke on my pneumatic squeezer for all the rivets with no issue.

I simply put the manufactured head on the flange of the VS-705 and may have needed to slightly move the rib out of the way to give the nose of the yoke room, and then let the plunger on the squeezer form the shop head on the flange of the VS-704.

I think I had to gently massage the VS-705 back into alignment but is was not extreme by any means. Once the skin was attached it all lined up.

Hope that makes sense.

 

[N546RV]

Well, the good news is that as of a few minutes ago, I got the botched rivet removed without ruining any parts. Unfortunately, the rest of my evening is booked, so no chance to do anything. Hopefully my new squeezer will arrive tomorrow and I can make a second pass at this...

 

[N546RV]

Urgh. I did get that pesky center rivet set yesterday, but only after actually botching one with the new squeezer. (that's what I get for telling Josie that hand squeezers are basically idiot-proof!) Unfortunately, I apparently overestimated how easy squeezing the rivets on the end would be. I've now botched and drilled out two rivets in each of those holes. I even tried going back to the rivet gun, and despite taking what seemed like a whole lot of time to really examine my positioning and such, I still clinched one.

Time to find some local help, I guess.

On the plus side, my technique for drilling out rivets is getting pretty [deleted] good.

 

[Flyin'Bryan]

Are your rivet shank lengths correct?

First of all - keep up the great attitude - always find the good in the things you are doing. I love your last comment. Believe me, if you are able to successfully drill out AN470 rivets in less than optimal locations, then that is truly a skill worth noting, and one to be proud of IMHO.

Are your rivet shanks the correct length after inserting them into the parts, or are they a bit too long? If they are long see my previous post about cutting down a longer rivet to the correct length with a rivet cutter. Otherwise, take a pair of hand seamers, dig out that trim bundle of small aluminum rectangle sheets that you should have received with your empennage kit, and create some mock ups of the parts with the same angles. Then mark, drill, debur, and dimple the holes, and practice setting the rivets on that. Another set of experienced hands and eyes is also a plus as well.

If you are clenching the rivets with the hand squeezer, then one other possible cause of this is that you are squeezing both handles together, causing the yoke to move to an angle other than 90 degrees to the rivet shank. You should endeavor to keep the stationary handle as straight as possible (linear with the rivet shank, with the yoke face at 90 degrees to the rivet) while you squeeze the other handle closed. This is usually the problem if you notice the shop heads of the squeezed rivets are uneven, with one side being slightly higher or lower than the other side, or they may even appear oblong or egg shaped.

Don't fret - you will get past this.