Done with page 23-02 and the Longerons

I even spent some quality time with my freshly minted Longerons

The hard part was the bending of the last 6" at a 4 degree angle.
I have the feeling to have gone through an initiation after spending almost a week on this page 23-02.
BigJohn method worked well but what helped most is that I bought a 2 pounds rubber mallet. The one I was using was half that. The instructions are not very clear in this regard: what is a "Heavy Soft Face Hammer"? Even so, I still discovered a few things: when you are finished bending the end to the right 4 deg. angle, you find out that the end is also bending downward. You then unbend it upward to find out that it is now bent only 3 deg... etc
This thing has a life of its own!
When eventually I was finished, it dawned on me that I had marked the beginning of these 6" ending the longeron with the initials of "Start Of Bend", the term used by VANs and I found it was very appropriate!

Section 23 Started but....

... In the last couple of days I had to fight a battle on two fronts:

• I worked on the infamous Longerons bending, a well known ordeal requiring patience and lots of concentration


• My laptop died on me, without warning, leaving me naked in the middle of my tax filing entirely relying on Turbo Tax

I am glad to have emerged from these battles with no loss and confident about the future of this project. I am writing this on my new laptop, a cheap HP Pavillion, after finishing tonight my two longerons bending. I have been lucky, first to have a back-up only 1 month old and that the disk of my dead laptop was intact, allowing me to recover it's content (with the help of the "Geek Squad" from Best Buy).

As fort the Longerons, here is page 23-02:

I avoided the crude method of bending described above by VANs and requiring lots of banging. After reading about the hardship of some fellow builders with the hammering, I bought a Longeron Die which allows to do the bending in a vise. It is still a cumbersome painstaking process because a great precision is needed to conform to the curve on the template. It took me two days to do the two longerons because of the learning curve (pun intended!). I could now do one in 1 hour... too late!

I still have a problem with a "straight bend" at the end that I can't do with the Die. I need to consult the VAF Forum.

Done with section 22

I did the lower firewall sealing with the Firemaster sealant I received from VANs. What I received was not what I expected in term of usage. It is a dispenser that requires to mix the full content which was about 10 times what I needed. I dismantled the dispenser and did a mixing of only what I needed. Messy but doable! The question is: will the unmixed left over be still usable when I need it? Overnight the mix cured well, I was impressed that the unused mix popped out of the cup providing me a flexible molding of the cup!

Page 22-05

No need to turn the assemblies upside down to do the job as the picture would suggest. There are not that many rivets that riveting from below is painful. The mating of the Forward Assy to the Mid Assy was not too tricky, just a few push & tugs. One problem you will face is the rivets on each side of the steps cannot be set without unscrewing the steps. No big deal, takes only 10 minutes. You may waste more time figuring out how to rivet around the steps. I went through a few builder's sites looking for hints until I found that Marty mentioned the problem and the solution.
I am done with section 22, except for the ProSeal application and riveting of the lower firewall shelf. I hope to receive the ProSeal late today if UPS makes the 2 days shipping from VANs.
Here is how my plane looks now:



Are not the steps inviting to climb in?

Sight Glass + Fuel Tank in cockpit = Bad Mix?

Yesterday I had the visit of a neighbor pilot, just back from Sun'n Fun. While I was telling him about my mulling of the Gas Tank option and that I was concern about getting a good seal around the sight glass, he told me the following scare he had in his aerobatic Christen Eagle a few years ago:
He was flying with a passenger in the front seat about 13 miles from RDU. His passenger told him he was smelling gas and shortly after he too started smelling gas. Then the passenger told him he was seeing gas dripping at his feet just under where the gas tank is located in the Eagle. He called an emergency, cut all power leaving only ignition and started climbing, waiting for the engine to starve at any time and trying to get enough altitude to glide to RDU. He managed to land on runway 23 with the fire trucks waiting... very, very soft landing! By this time 6 gallons of gas had dumped on the floor of the cockpit. There was a crack in the sight glass of the gas tank. He later found out that there was an AD for the Pitts which is the certified version of the Eagle. This AD required to change the sight glass every 4 years - his was 20 years old and as the Eagle is Experimental this AD had been missed by the previous owner.
This enlightening story led me to decide to build the tank rather than buy the pre-built tank. Although this might seem counter intuitive, here is what I think:
- There is no way to predict if a problem similar to the Pitts' AD will happen on the RV-12. Likely VANs was careful choosing the plastic use for the sight glass and the way it is fastened. However the oldest -12s have 2 years of flying and are not that many.
- In case problems arise in the future I will be in better shape taking care of the fix if I built the tank myself.
- I might well, as several -12 builders have already done, decide not to wait for a problem to close the sight glass window and put a mechanical level sensor. Here again having built the tank will make things easier.
Conclusion: I will order my finishing kit without the prebuilt tank option.

ago

Page 22-03 & 22-04

Completed page 22-03, except that I am waiting for the ProSeal to rivet the Firewall shelf.

Page 22-04:
This is an easy page, done in less than one hour.

Page 22-03

The first thing I notice: need some Pro Seal. This time I cannot use "great stuff" as I did for sealing the foot step in section 21. After investigating VAF and EAA 1114 for the best source, I ordered a small quantity from VANs, will take two days to arrive. This investigation brought back the question of the option of buying the fuel tank prebuilt as it is the main user of ProSeal. Still pondering the option with just a couple of weeks left before ordering the finishing kit. The question I have to answer is: Do I trust myself more than the guys that will build the fuel tank for me if I put down the $400 extra for the option?
Do I? Do I?

Answer later...

Done with page 22-02...

... and my take on it: it's not for sissies!
There are a few errors or omissions but they are pretty trivial like not mentioning to dimple a platenut or countersink a rivet hole that is matched by a dimpled hole. No big deal for a builder that has reached this phase alive. The problem is that VANs made the economy of several pictures and instead offers only depiction of the assembly once completed. The trap is that if you rivet some parts in the wrong order you will have to undo it (don't ask me how I know). I will not offer any hint beside the obvious: go slow and read instructions twice before doing anything irreversible. If you understand well how the whole thing comes together ahead of riveting you will be in good shape
Actually this page is a great initiating process, if you get through unscathed (or like me with minimal damage to your ego...) you are good for the rest of the build.
Now let's proceed to the next page.

Starting Section 22

This is what section 22 is about:


Page 22-02
Has bad reputation among builders and for good reasons. Here are Builders Web sites links documenting the problems:
Marty's RV-12
Schmetterling Aviation
Also searching for Page 22-02 on VAF may be helpful.

s

Page 21-20 and End of Section 21!

It may look simple but you will likely face the two problems I had:

- The system block studs are fastened with tiny nuts (MS21042-08) that require a 7/32 wrench. These wrench are not commonly found: Lowes does not carry them neither Auto Zone etc... At Sears I found a Midget Wrench set of good quality for $20. You probably can buy only one wrench at a specialty store online but with the shipping cost you will not do much better.

- You cannot fasten the studs without help and it will be easier if you tilt the fuselage on its side.

Finished my Plane!

I'm done with my build, I quickly painted it in blue and flew to Sun'nFun where you can see it on the picture




April's Fool Day!!!!!