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Trailing edge rivets

AviatorJ

Well Known Member
Was looking for examples online of some set trailing rivet sets. Came across this picture-

http://www.aclog.com/rv-9a/images/Empennage/emp/DCP_1315.JPG

Looks like he chose to alternate shop heads on each rivet. My question is are the non-shop ends driven far enough? I ask because I did my elevator trailing edge's last night and they look really similar to that middle one.

If that's good then I'll call it a day, if not how do I best drive that rivet down without tearing up the edge... back rivet, mushroom, ect?
 
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Made a link to the picture because it's pretty big and don't know how to resize embedded pictures.
 
Trailing edge

Not a 10 but here's a photo of my 7 rudder.
2uzfayg.jpg
 
Double flush

Looks awesome! I'm just about to do this to my practice flap.

Iv read that you half set with a back rivet set than finish with a mushroom.
Would love to hear your method

Thanks
I'm sure there are lots of methods.
First proseal the wedge and cleko the trailing edge to a piece of angle match drilled to the piece. Leave it for a week to set up.
Back rivet set is fine but be careful you don't let it hit the skin as it gets close.
First pass partially set every 10th or 6th rivet. Maybe every 3rd on the practice piece.
When you get to the end, partially set in the other direction. Keep making passes till they are all set about the same.
Repeat the procedure with the mushroom set shooting for flush shop heads.
 
On my -9A, after I'd prosealed the trailing edge, cleco'd it to an aluminum angle and let it set as Larry did, I partially set the rivets (installed alternating mfg head up and down along the trailing edge) with my pneumatic squeezer. Then used a back rivet plate and mushroom rivet set and rivet gun.
 
Same, sorta...

On my -9A, after I'd prosealed the trailing edge, cleco'd it to an aluminum angle and let it set as Larry did, I partially set the rivets (installed alternating mfg head up and down along the trailing edge) with my pneumatic squeezer. Then used a back rivet plate and mushroom rivet set and rivet gun.

I did nearly the same process as terrye. I used the 3m tape method though. After I set the rivets partially with the squeezer, I used a back rivet set on low pressure and gave each a shot (alternating) then finished with mushroom head. Extremely pleased with the work.

Ps. Always impressed with your work wirejock.. Very clean and nice
 
I have tried the 3M tape method but found that pure patience worked even better and with less mess. I've never done the proseal method. I do alternate shop heads on either side of the piece and slightly set with a back rivet set first. Then every fourth or fifth rivet, full set with mushroom. You mainly want to avoid fully setting them in order as it will cause a bend in the trailing edge. If you're patient and work them down slowly, you come out with a nice straight edge without any excess materials used.
 
Thanks
First proseal the wedge and cleko the trailing edge to a piece of angle match drilled to the piece. Leave it for a week to set up.
Back rivet set is fine but be careful you don't let it hit the skin as it gets close.
First pass partially set every 10th or 6th rivet. Maybe every 3rd on the practice piece.
When you get to the end, partially set in the other direction. Keep making passes till they are all set about the same.
Repeat the procedure with the mushroom set shooting for flush shop heads.

That is the process I used, except instead of a week, let the proseal and 3M tape sit for 3 days. I got my rudder down to take a look at that edge, it looks the same as my elevator and almost seems like instead of 3-3.5 rivets I should use longer ones... but per the Vans construction manual it states don't be tempted to do that.

I'll leave it for now until a Tech Counselor can take a look. Maybe the 10's just don't flatten out like on the 7. And I agree your work is fantastic.
 
Thanks

That is the process I used, except instead of a week, let the proseal and 3M tape sit for 3 days. I got my rudder down to take a look at that edge, it looks the same as my elevator and almost seems like instead of 3-3.5 rivets I should use longer ones... but per the Vans construction manual it states don't be tempted to do that.

I'll leave it for now until a Tech Counselor can take a look. Maybe the 10's just don't flatten out like on the 7. And I agree your work is fantastic.

Thanks
I just checked out your blog. Parts like very nice. Blog is easy to navigate too.
 
Thanks I appreciate that. They're far from perfect but my hope is structurally everything is on point, the rest can get covered up with paint.
 
On my practice piece, I used the back rivet and mushroom set method.
Thinking I might use my pneumatic squeezer to partially set the rivets and finish with the mushroom set (possibly a flush die in a C-frame rivet set)

Maybe this will become more obvious as I do it, but with partially setting the rivets in alternating directions, doesn't that leave small bumps every other hole that interferes with keeping the back rivet plate flush to the skin on the rivet I'm trying to fully set??
 
Double flush

On my practice piece, I used the back rivet and mushroom set method.
Thinking I might use my pneumatic squeezer to partially set the rivets and finish with the mushroom set (possibly a flush die in a C-frame rivet set)

Maybe this will become more obvious as I do it, but with partially setting the rivets in alternating directions, doesn't that leave small bumps every other hole that interferes with keeping the back rivet plate flush to the skin on the rivet I'm trying to fully set??

If you have rivets all inserted fom the same side, no. The factory side would be on the back rivet plate. Skipping around insures against pulling a curve in the trailing edge.
Now if you want every other rivet to be inserted from the opposite side, things may get interesting. I know some builders do it.
 
If you have rivets all inserted fom the same side, no. The factory side would be on the back rivet plate. Skipping around insures against pulling a curve in the trailing edge.
Now if you want every other rivet to be inserted from the opposite side, things may get interesting. I know some builders do it.

Thanks, Larry.

I've seen others mention inserting rivets from opposite sides and guess I just figured I would do that as well as jumping around like described in the plans. In the end, the alternating sides didn't seem to make sense, as you say, might make things interesting. I think they turned out pretty good.

VUKNIS1I1625ZbgxwN_SBaakyGOrZTO5tLDROaK0S5agVlRVEAOJqlliryYac2_SgVPJ9ZaJzKZGIhu2xoXyIi_zErA3rG4beSgjce4qrE1T50uDzj2Tub72zmRggnzS_SUuD29h-HmKrkDTmiSL24f85PmNWkJNWUQf19-Jwub7UU3huIfj5iyIw1JjS_21cVJ2uAwRJFHCRDKUGuoprLJ7jQkXQQcql5ByB5nSgypZNXm4GyIsht37JM5ePUCUICsEAZURmjAg3_5MqnlMGLJAnExxe2T_nuX-NohpdHPRdn2KDZO_1pdCO1TL2PkHEzBJRW1a7GzRc60K7O44FU6pM1jfZ1f2fH1bJ100MoukXyO883n9ZGE3MhF0H9c4IbCvXTe1176sbLlTRnIr_krMX7VoFwzaNPagGar3gmez2JS5Y9o3OWMLU4XAmvKQMDd-BNkNIdHiUKWXf7NtDmaMAGiSIUVLETCYnIyGz61ytVk37RQV2J6Omrc4GUOCsb_4KMbocjug4ZE3X_cha0Kj4jouOtpFsBcHnXAgjP1X6PX-C4y-g8LCOhaQwZX6BjUK=w1199-h900-no
 
Mushroom head for Trailing Edge

Why do you use the mushroom head to finish the trailing edge?

Can't you use the back-rivet set to finish it?

I found that the back-rivet set can dent if you don't "end" perpendicular to the skin.
However I'm not able to use the mushroom head without either pounding the back-rivet plate or keeping it too much on the trailing edge pounding the skin (and stiffeners).

Which one should I "pound"?
 
Hey Justin.

I too really like your blog. I agree with Larry that it is nice to navigate through and I've found it very helpful thinking through some of the build decisions that you've already made and articulated.

One point I have is with respect to alternating the shop and manufactured heads. It makes sense to me to do that on the rudder where both heads are equally visible but i don't think it makes sense on the elevator where it would seem to make more sense to put the manufactured head up for cosmetic reasons. That's what I did. I know that the main point of the post was how to set the rivets but I thought I would mention it.
 
Pounding

Why do you use the mushroom head to finish the trailing edge?

Can't you use the back-rivet set to finish it?

I found that the back-rivet set can dent if you don't "end" perpendicular to the skin.
However I'm not able to use the mushroom head without either pounding the back-rivet plate or keeping it too much on the trailing edge pounding the skin (and stiffeners).

Which one should I "pound"?

Marcel, I don't see a response to your question so I'll give it a try. If you can position the trailing edge at the edge of the back rivet plate, you should be able to "pound" the rivets without pounding the plate. Just make sure to check the position of parts every time. Nothing ruins a day like missing the plate.
 
My instructions said straight trailing edges was one of the most difficult parts of building a flying surface. With that in mind, and being far from accomplished with the rivet gun, I decided to find a way to get good reliable results with a dead straight trailing edge. I'm accustomed to building race cars in jigs and fixtures so Van's "in the air" method is all new to me, and a little scary. Point is, I'm blessed with tools and equipment most of you do not have and do not want to buy. One of them is a six foot by six-foot by .625 steel blanchard ground surface plate flat and square to .010. With this one can usually get a true result.

I milled an eleven-degree angle in a 4" x 2" x .5" steel block. This matches the angle of Van's trailing edge internal aluminum strip. The idea here is to end up with two parallel surfaces to squeeze against. Also, the oversized block insures everything stay flat and true without any dents or smiles in the skin.
I invested in the Numatx air over hydraulic squeezer because its half the weight of the pure pneumatic squeezers and comes with a foot pedal which is amazingly handy when you are trying to keep a couple of components aligned as is the case with the trailing edge rivet squeezing process.

Here is a picture of the simple steel block with the eleven-degree angle.

te1.jpg



te1.jpg
te2.jpg



te2.jpg


Above is the block positioned on the bottom of the trailing edge offering two dead parallel surfaces for the squeezer to work on. I installed the largest diameter flat squeezer set I had in the nonmoving side of the squeezer, and held it firmly over the shop head, then brought to piston up against the steel eleven-degree wedge block, and when all was well aligned squeezed the rivet. I had the entire structure clamped down on the surface plate so I could maintain a dead straight trailing edge with no problem.

I realize all this is worthless without the tooling but if you have a squeezer your local machine shop can make you the angle block or I'll send you mine, my next RV build is well over a year away :D
 
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Proseal?

Did I see someone say they did NOT use proseal on their trailing edge?

I am about to the point of riveting my elevators and will need to order proseal for this job only. Seems like I am going to have a BUNCH left over. Is there a local alternative that people have used and like and might be available in a small amount?

I do have several fellow builders in my area but nobody with proseal that isn't hard as rock.

Jim
 
There are a few that have used the 3M tape vs proseal. I think this is what is in the RV-14 plans.
Here is a link to the stuff in the Vans store.

I ended up going the proseal route as I knew wanted to get some experience dealing with proseal prior to working on the tanks. All in all it wasn't a terrible experience. I did end up buying this tape and used it for the shims attaching my vertical stab while I drilled them.
 
Proseal

Did I see someone say they did NOT use proseal on their trailing edge?

I am about to the point of riveting my elevators and will need to order proseal for this job only. Seems like I am going to have a BUNCH left over. Is there a local alternative that people have used and like and might be available in a small amount?

I do have several fellow builders in my area but nobody with proseal that isn't hard as rock.

Jim

Vans sells a small bottle.
 
That is good to know! I'm thinking about the tape, I feel like I have plenty of past experience with proseal!;)

Is the bonding component just to help keep the edge from warping during the riveting process? (There wasn't anything quite like the split trailing edges on my 6. I think the elevator skins are made of dinosaur skin or something like that:p


No, wait, my shoes are made of dinosaur skin!
Jim
 
Did I see someone say they did NOT use proseal on their trailing edge?

I had a very early 9/9A kit. If I remember correctly, no mention was made in the plans to use ProSeal or tape on the trailing edges. I used lots of weight (sandbags) and clecoes to hold everything in place while riveting. The results were OK, but if I did it again, I would try the 3M tape.
 
I had a very early 9/9A kit. If I remember correctly, no mention was made in the plans to use ProSeal or tape on the trailing edges. I used lots of weight (sandbags) and clecoes to hold everything in place while riveting. The results were OK, but if I did it again, I would try the 3M tape.

That is good to know! I'm thinking about the tape, I feel like I have plenty of past experience with proseal!;)

Is the bonding component just to help keep the edge from warping during the riveting process? (There wasn't anything quite like the split trailing edges on my 6.

As Mark mentioned, originally the T.E. were just riveted without bonding.
The bonding isn't considered a structural requirement (though it does have a small structural benefit). It was added to help people get a better finish and straighter T.E. when riveting.
 
I used Loctite Hysol slow cure structural epoxy, mostly because I had it. In retrospect, with the squeezer tooling I previously pictured in this thread, I don't think any adhesive is necessary.
 
Vernon,

I may have misread, did you put the manufactured or shop head next to the steel block? I think I am going to mill a block like you showed and try that.

Questions - did you start with 1/2" thick steel plate? Does that leave enough room for the two skins, wedge and block for the squeezer?

Any issues of the angle block trying to "squirt" off the trailing edge when you start to set the rivet?

Did the block need to be as long along the edge as it appears in the photo or would a short section work as well? Something less than the rivet spacing is what I'm thinking.

Did you have the block fastened to the bench as well as the elevator?

Thanks for the info and the pictures!

Jim
 
Vernon,

I may have misread, did you put the manufactured or shop head next to the steel block? I think I am going to mill a block like you showed and try that.

Questions - did you start with 1/2" thick steel plate? Does that leave enough room for the two skins, wedge and block for the squeezer?

Any issues of the angle block trying to "squirt" off the trailing edge when you start to set the rivet?

Did the block need to be as long along the edge as it appears in the photo or would a short section work as well? Something less than the rivet spacing is what I'm thinking.

Did you have the block fastened to the bench as well as the elevator?

Thanks for the info and the pictures!

Jim

subscribed. Inquiring minds want to know.
 
Vernon,

I may have misread, did you put the manufactured or shop head next to the steel block? I think I am going to mill a block like you showed and try that.

I put the non moving end of the squeezer, fitted with the largest diameter flat set I had on the manufactured head and I put the manufactured head on the top skin for aesthetic reasons. The plate was held under the TE and addressed by the moving plunger.

Questions - did you start with 1/2" thick steel plate? Does that leave enough room for the two skins, wedge and block for the squeezer?

My squeezer has two push rods of different lengths so I can make it work with anything I can get between the jaws. Cleveland sells flat sets in .063 height increments plus an AN 960-10 washer (3/16 to revert to common folk descriptions) can be had in .031 or .063 thickness. These combinations give you endless combinations to work with.

Any issues of the angle block trying to "squirt" off the trailing edge when you start to set the rivet?

None, that was the reason to make the block in the first place.

Did the block need to be as long along the edge as it appears in the photo or would a short section work as well? Something less than the rivet spacing is what I'm thinking.

My block is 4" long and that's adequate. You want a fairly long block so every squeeze keeps the TE dead straight.Just be sure to chamfer all the edges so you don't make any visible impressions in the T4 aluminum. It's a lot softer than the 1030 block.

Did you have the block fastened to the bench as well as tme elevator?

No No, with the elevator (or rudder or wing) clamped to the table you want the entire squeezing mechanism to float and find it's best alignment. That's what the entire cleko/match drill then rivet process is all about. Everything in front of the TE is solidly riveted (hopefully) so you want to recognize that integrity and work with it.

Thanks for the info and the pictures!

Jim

I hope this works, the forum does not seem to like inserting information in existing text strings. We will see what we get :D
 
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