To prime or not to prime…

Many wars have been fought over the choice to prime aluminum or not. Many thoughts, considerations, pros and cons exsist over the use of primer on aluminum aircraft.  I made my decision, and I’ll live with it: Minimum primer.

Here are my guiding rules about decisions in building my aircraft.

  • First, did Van’s tell me to do it? That is an overriding decision point.  If Van’s said do it, I do it. Remember, I’m not an aeronautical engineer, I’m an aircraft assembler.
  • If Van’s has no preference, I ask: “Would Cessna do it?  Cessna aircraft, and the Cessna 172 in particular, are the safest aircraft in the sky. My motto is ” Cessna Safe”.
  • Finally, for more modern options (that are not related to safety of flight issues) I look at what other guys on the forums have done. BUT only AFTER they have some time with it.  Beware of advice from folks who have “heard from a friend…” or “read this on the web…”

Avionics is a BIG gray area here. Cessna does not use Dynon Avionics, but how cool is THAT in an experimental aircraft.

Murphy’s Law of Selective Gravitation:
“If while working on a large object with tools (car, airplane, boat, etc.) the dropping of any tool will cause the said tool to roll to the exact center of the object.”

Be sure to build a nice paint stand.

Resist Temptation!

There is a common riveting mistake we will all make. Sometime, the bucking bar holder (usually me) will push the rivet slightly out of the hole, and when the hammer hits, is squeezes funny, and the rivet head stands out slightly.  You might be tempted to say “Well, maybe if I hit it again, it will look ok…”

STOP!!!!

Anytime you use the word “maybe” in a sentence like that, you are probably about to make a mistake.  Don’t even try. Just drill out the old rivet (these are usually pretty easy) and start again. Don’t give into the temptation of a quick fix that you will regret later.

Murphy’s Law of Thermodynamics:
“Things get worse under pressure”

Rudder

Sharp tools..

When I was first setting up my empennage, I went over to my shop partners band saw and cut a stiffner down a little.  It was aluminum, and not very thick, but still too a great deal of time to cut.  Since I had never used a band saw before on aluminum, I did not think much about it.  Later I was talking to my hanger partner and told him I had used the band saw, he said “That blade needs replacing.  It is a scroll blade and not very sharp.”  So, I went out and got a new blade (the right size, and type) and MAN! what a difference it made! Clean, smooth and FAST cuts are now the standard.

So, just a reminder:

  • Start your project with new, sharp blades in all cutting equipment.
  • Buy NEW drill bits (stay away from eBay). They are not expensive and it will make a BIG difference as you start your new project.
  • Get GOOD tin snips. Pay the extra few bucks.
  • NEVER try to cut hardened steel with your band saw.  You’ll kiss the blade good-bye.
  • Never be holding your cat when you turn on your shop vacuum.

Vertical Stabilizer

Murphy’s Law, as it applies to aircraft…

So, I took the EAA RV builder’s class. I went over to Dan’s house and helped him a little with his RV-7. I bought and built the practice kit. I attended the EAA RV builder’s class a second time with Tom. Built ANOTHER test project.  Bought all the right tools, built a very nice work table. Got absolutely EVERYTHING ready. Finally, I got the tail skin together, cleaned and drilled and deburred and READY to go!  And when I went to drive my VERY FIRST rivet into my project: BANG!   I missed.

Big dent in tail skin.

BIG dent in tail skin

So, for those of you who have never heard of Murphy’s Laws, here is the First Law:

“If anything can go wrong, it will go wrong”

  • First Corollary: “In a manner to make you look the most foolish”
  • Second Corollary: “In a manner that will produce the most damage”
  • Third corollary: “Only on the most expensive parts”

*sigh*

When working with pre-punched parts…

When working with pre-punched parts, do not be shy about writing on them with a Sharpie©.  Getting the correct orientation is half the battle, and keeping the victory means documenting it.  Sharpie marks can be easily removed with MEK or Acetone.  Keep a gallon of each around.  Keep it away from kids tho!

I discovered that if a pre-punched part from Van’s does not appear to fit correctly, I’m probably doing something wrong. Almost NEVER is it a Van’s problem.

Horizonal Stab with writing on it

Keep Writing!

Building other stuff….

OK. when you start building your RV-9A, you discover very quickly what OTHER stuff you need to build first.  How about the best plane building workbenches ever?  Check out the bench and the plans for the EAA Chapter 1000 work bench at: http://www.eaa1000.av.org/technicl/worktabl/worktabl.htm

Note that you do not need to follow the plans EXACTLY. I made a long table and a short table, so I needed to buy only ONE sheet of plywood.  Actually, later I bought another sheet to have on top, so I could drill, cut, mar and generally abuse the top, then just give it to the next builder and get another.  Here is what that looks like:

EAA 1000 workbench  - customized

Getting the Blog Started!

Greetings Friends!

Well, after two and a half years of building, I’m finally building the blog!  I’m Dave of Tom and Dave and we are building a 2 seater experimental airplane.  Since there are thousands of these planes flying, I believe it is more accurate to say we are assembling an aircraft.  This is an aluminum design, with a standard aircraft engine with a cruise speed in the 180mph range (we hope). The plane is a Van’s Aircraft RV-9A. This is an aluminum, two-seater side-by-side cross-country plane with a 160 hp engine.  Check out the factory at www.vansaircraft.com

So, how does all this start?  With a little aluminum.

Empennage kit for a Van's RV-9A

Empennage kit for a Van's RV-9A