I have suspended following the instructions of section 14 (Rear Spar, Stub Spar, Hinge brackets) to make a decision about priming. Section 14 requires quite a bit of riveting and once riveted, the parts cannot be primed. I am not an avid Primer for two reasons: it is not required by VANS for most of the parts as most parts are Alclad. There are endless debates about the necessity to prime beyond what is recommended by VANS. The most compelling case for priming everything, including Alclad parts is for those who will keep their plane in a coastal area because of the saline atmosphere. The second reason has to do with the extra work, hazardous nature of the chemical products involved and all precautions that have to be heeded to make the priming process safe. I took the advice of a fellow EAA chapter 1114 builder, Noel Fallwell. Noel has been through the full priming enchilada with his RV7 and his position, in retrospect, is that he would not do it again. He gave me a good lead to solve the problem of parts on which the Alclad has been removed by the manufacturing process (i.e. deburing, countersinking, ...): use an Alodine treatment. The interest of the Alodine treatment is that it is a chemical reaction that does not add weight and that provides good corrosion protection. The other interest is that it is a cheap treatment to have subcontracted. Noel gave me the address of a Greensboro company that he used in the past and I was able to confirm their rate ($50 a lot which is all what fit in one basket). They use two baths, one for cleaning and one for "alodining". An additional plus is that they can provide your batch treated back the same day.
This is what I will do for the wings. The consequence of this decision is that I had to debur all parts I want treated before taking them to Greensboro, hence the little hyatus in my building process.
More soon....
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