Practice: Project 2 continues.

The control surface practice project continues.  Only rolling the leading edge, and its final riveting, remains.  Turns out I'm short one pop rivet, but that's okay.  I had some challenges getting a bucking bar at the apex of the ribs, so my rivets there aren't straight.  In fact, I had to drill out about 5 rivets today.  The good news is, I have a lot more confidence in that procedure now, so I feel like I can handle that on the real plane.  

On the trailing edge, you're asked to dimple both sides, then back rivet using the mushroom set.  The image above is me taping in the rivets.  I was really curious what this would ultimately look like.  Here it is.  Kind of neat.

I also found out what happens when you let the rivet gun go for a jog.  Ouch.

And finally, here's my air tool manifold mounted on the table leg.  The rivet gun and pneumatic cleco tool are connected right now.

Other entries for project 2 are here and here.

Setup and Project 2.

My new pneumatic cleco tool arrived, to replace the troublesome one, and can open clecos every time!  I noticed that the piston on this tool retracts much more slowly than the first one does.  That might suggest that the original one really did suffer from the leak around the piston that I noticed.

The manifold and supporting parts came in too.  I assembled it with Teflon tape and checked for leaks.  There is a very slow leak, about 30 psi in 8 hours.  That's not worth chasing down.  This manifold will be mounted under the table so I can negotiate the air tools and hoses easier.

The pop rivet set I ordered for the trailing edge of the practice control surface came in.  Turns out, the head of the nail doesn't fit through a #40 hole.  I had to get creative:  First I tried using a smaller nail, but it was too short for the pop rivet tool to grab on to.  Ultimately, I managed to get in there with some channel locks.  Without leverage, it's hard to squeeze the handles enough and it's a challenge to keep the dimple lined up with the hole. Turns out, on two holes, the dies weren't well aligned and I had to "upsize" those holes to a #30 to get the rivet to fit.  It won't look pretty when the rivet is set.  In retrospect, I should have done this.

Other entries for project 2 are here and here.

I also went to the local EAA chapter meeting last Tuesday night.  Joined and met some nice new friends.

Practice: Toolbox kit complete.

Completed the toolbox kit.

From this:

 To this:

Total build time:  6 hours 4 minutes.

A lot easier than the other projects, probably owing to having spent time with the others prior to this one, and that this project was mostly just match drilling and riveting.

What I learned:

• Rivet squeezer is much more reliable, at least in my hands, than the rivet gun.  I used the squeezer at every chance I had since, with the other practice projects, I didn't always get the head flush with the work and ended up with a nasty gap.  I had only a few rivets set with the squeezer that weren't flat on the shop end.  These probably occurred since, when applying force to the squeezer, I didn't maintain the squeezer in the same plane.

• I couldn't figure out how to set the rivets on the bottom half latch.  I tried every permutation I could think of with the tools at my disposal.  Nothing would fit with one of the holes cleco'd.  Ultimately, I left the cleco off, tapped one rivet a few times so it would set slightly, then banged the other one, adjusting the latch as I went to make sure it was straight.  After the second rivet was fully set, I went back to the first to finish it off.  This caused the rivet to squish in between the two metal layers, creating a gap.

• Even though the cupped set, for the universal rivets, typically stays put on the head, it can walk.  I ended up mashing one universal rivet head because I got too cocky.

 

• Sometimes, after match drilling, deburring and dimpling, the rivets still were a tight fit.  So I "rematch drilled" and redeburred on about 6 or 7 rivets.  Wonder what's up with that and if that technique would pose structural integrity risks on the airplane? 
• The hinge and handle could not  be cut with my snips.  In fact, the blade is now ruined.  So, I tried cutting them on my band saw.  Though it worked, it probably stressed out the blade.  The wire got red hot!
• I used the dimple dies (dice?) in the squeezer for a few of the corner holes that wouldn't fit in the DRDT-2. 
• I had a really hard time deciphering the description regarding the hinge orientation.  I eventually found these two pages that helped me get some confidence:
• Wendell Engelien's RV-6A
• Darren Rickett's RV-8 (link no longer valid)

Here are some shots of my riveting.

 

My pneumatic cleco tool from Avery didn't work.  90% of the time, it would only partially open a cleco, then stop.  I finally tracked the problem down to an air leak around the piston.  When it was leaking, it couldn't open the cleco.  The few times it had a seal, it could open the cleco fine.  I'll let Avery know so they can replace it for me.

Also, seems the time lapse software is failing me.  After a few hours of running, it starts to drift and takes images at longer and longer intervals.  For example, today it was setup to take images every 10 seconds, which it did, initially.  By the end of the build day though, it was taking images every 31 seconds.  That sucks, since I was calculating the time I spent working by how many images were acquired.  I'll mess around with it and see if I can track the issue down.  For now, my build times aren't accurate.

I'm going to switch to using a butane soldering iron for scoring the protective vinyl.  The cord from the electric iron 1) gets in the way of everything and 2) is going to get sliced by a sharp edge, which would provide me with a brief light show and an undesired spot weld.

Finally, project 2 (the control surface) is on hold.  I had to order this pop rivet set so I can dimple at the tapered edge of the ribs (the vise is cool, but I was concerned that it may still have a challenge getting into tight spots).  I broke my (borrowed) #40 countersink bit trying to make the suggested tool in the plans.  Turns out the guide hole on the bit is #30!  I didn't realize that, so it snapped right off due to the friction.  From now on I will check these things.

Here are my outstanding issues that need to be solved prior to my wings coming:

• The new bench grinder itself, or the wheels are poorly balanced.  It shakes, rattles and rolls.  Dressing didn't help.
• The drill press bits always wobble.  The chuck seems center, but the collar doesn't.  Not sure what to do just yet.

Practice: Project 2.

Time to make the practice control surface.

Had my first experience drilling out rivets since I got too excited and riveted the reinforcement plates to the spar without the ribs.  D'oh!  It caused me to bend some of the pieces and ream out the holes to a larger diameter.  So a potential space between parts became an actual space.  When banging the new rivets, their shop ends graciously filled that space preventing things from sitting flush.  Oh well.  Better to learn now than later.

Also, it's really dang hard to use the Main Squeeze and keep the factory end of the rivet flush to the work.  Takes some planning on your part.  If you screw it up (and by "you", I mean "me"), you get a rivet that lives in places it shouldn't.  I'm guessing I'm going to end up with a pneumatic squeezer to save my hands and to help keep things properly aligned.  Turns out, those bad boys are pricey though.

I really need some rubber pads on my vice.  The vice chews through anything that's put in it.  You can see some of the clamping marks on the spar.  And if you're curious what the pretty mark is on the reinforcement plate, that was from my band saw.  I wanted to see if slicing off a rivet head using that machine was practical.  Turns out it works pretty well...if you're not concerned with anything else that the blade will touch.  So, not an option for true work.

Note:  Don't drill through the length of the rivet when trying to remove it.  Drill a hole in the head and see if you can push it off with the drill bit.  If not, bang the edge of a file against the head with a hammer.  It will pop right off.  Then use a punch to hammer out the body.  Speaking of which, I really ought to get a punch.  I was using a thin allen wrench as a punch.  Shhh!

Pages I consulted during this project are below.  Thanks guys!

• http://vitsrv.blogspot.com/2012/12/rv-training-project.html 
• https://web.archive.org/web/20130301013146/http://www.etigerrr.com/ClassTutorial.htm
  
  • I wish had found this page prior to starting.  I came upon this page when trying to learn how to use the rivet squeezer.  I appreciated the methodology used with the tin snips.  My approach left a nasty, ratted-out edge.

So far up to 6 hours and 6 minutes on this project.

Other entries for project 2 are here and here.

Practice: Project 1.

Time to learn how to rivet with the practice project.  What an experience.  Key takeaways:

• Read, read, read.  Understand clearly what you're being asked to do!
• Check, check and recheck every step before you do it.

I had a number of mistakes such as countersinking for round head rivets, using the wrong dill bit size and letting the (2x) rivet gun go for a walk when pounding.  As you can see from my work, it ain't very good.  Best to learn now rather than with an airplane part.

The rivet gun wouldn't work initially.  I spent some good time trying to get it to go.  Turns out I needed to operate it in different orientations.  Apparently, if it isn't used for a while it gets gummy inside.  Once it loosens up, it happily bangs away.  It's a pretty cool tool.

If you have a countersunk hole for a rivet that isn't made for such a hole, it will kindly fill up that (what should be) empty space and separate adjacent parts.  You can see how my seam didn't sit flush.

Total time spent 5 hours and 16 minutes.