Primed left elevator skin

Primed left elevator skin and trim. The boat is on the water with new antifoul, two new pumps and a fully working engine, so it is time to start building again.

HS ribs deburred and primed

Deburred an prmed the HS ribs.

Primed the spars

Deburred and primed the spars. I have to ventilate the house due to the fumes, but when the outside temp is -20 C it gets rather cold :-)

I also replaced the LCD screen on Olaugs Asus EEE after it had rough landing on the floor. Makes me wonder, that LCD screen is tiny. Hooked up to a NI Compact RIO or some other compact embedded system. Or an industrial touch screen and embedded NI logging system.

More priming

Did some more priming. Riveted on the brackets for the elevator hinges and the hinge nut.

Priming elevator parts

Primed some elevator parts. Ordered a bunch of vareous CherryMax rivets after looking at some videos at EAA "Hints for Homebuilders". Replaced the sole 4/32 solid rivet with a 5/32 rivet in the R-410. It simply looked way too strange with three different kind of rivets there.

Elevator skeleton and priming

Made the skeleton for the right elevator. Primed the skin, stiffeners, skeleton and the rest of the bits for the rudder.

Primed the rudder skeleton

Primed the rudder skeleton parts with the P05 Strontium Chromate Epoxy. The aluminum plate from Sweden arrived within a couple of days last week.

Fixing up the VS skin

Finished trimming, deburred the skin and skeleton and primed the VS skin.

Primed the VS skeleton

Primed the HS skins

Primed the HS skins and touched up some on the VS spar.

Finished bucking the skeleton

Did the last few rivets on the skeleton of the HS. Had to drill out two rivets that were bad, but it is remarkable how fast one learn using the rivet gun. Also riveted on the 404 spars, and this results in using pop-rivets on the 407 spar/skin interface. Pop rivets doesn't look so nice as flush solid rivets, but it will be easier to get it properly done, nice and straight and good riveting. I think I will chose that path as a general rule in the future as well - higher probability of succeding with a good solution the first time before beauty, he he.

Found out that the HS-410 was a mm or so too large in the ends so it would interfere with the skin. Should have seen this long ago, but didn't, so had to file down the ends, polish and prime (with Zinc Chromate).

HS ribs primed

Deburred and primed the ribs for the HS. Fixed the sligthly conical shaped HS-406 by strightening out the ribs. The HS-406 ribs had an oval shape when looking from top to bottom making them point outward when riveted on to the spar. Just by making them straight made them parallel by approximately 1 mm.

Now I have to decide if the HS-407 spars are to be riveted on now or later - solid flush rivets or pulled rivets on the skin on the HS-404, hmmm ....

Priming

Had a can of Zinc Chromate laying around, so I decided to give the HS-409 a thin layer of the stuff on top of the WG6650, giving them a real chemical corrosion protection, since it is non alclad and will be almost like an external surface. The surface of the Zinc Chromate is semi gloss while the WG6650 is matt, which will make it very difficult to remove grease and oil.

I will order some P05 (Strontium Chromate epoxy) and Derinoxal. According to the conversation I had today with a representative from the factory (Monopol in France), that is what is used on airplanes - period. It will take some 4-6 weeks to arrive, so I will use what I have for now. Untill I get the real stuff I will use WG6650 on all parts and a thin coating of Zinc Chromate on some places. (If this actually is better than bare alclad and zinc chromate along contact lines, I don't know).

Priming spars for HS

Parts for the front and aft spar on the HS were primed this evening. The primer used was the WG6650 Wash Primer from Monopol.

Front spar on HS, number 2

This time I got it right with the new parts. The 8 degree bends also became much strighter and at the right place with the small break from Clas Ohlson. Using a mallet to create the bends, as described in the manual, works but is very inaccurate.

Regarding primer, I need some washing/etching thing before applying the WG 6650 wash primer. At Aunes Karosseri they have never heard of such a thing, but another car paint specialist could get some DuPont/Corlar 5717S Metal Conditioner. He could only get 6 l, and I have to purchase all of it because it is something they never use. When reading the technical manual of the 5717S, it is meant to be used on ferrous metals and some other. Aluminum is not mentioned, so I am not sure if this is the right product at all. Monopol in France say I should use something called DERINOXALU, but have not been able to get it yet.

Primers

Got some wash primer from Monopol (Wash Primer WG 6650) from a local car body shop. I allso got a rattle can of "houshold" metal primer (Quick Universalgrunning from Scanox) which is an alkyd based primer with corrosion inhibitors (supposedly).

The wash primer is green and the other one is gray. SB means Scotch Brite has been used on that area. It is possible (but hard) to scratch both off with my nail on the area not scuffed with scotch brite. The area scuffed with scotch brite is much harder to scratch off. I have to use a knife or a sharp object and I take off just as much aluminum as I take off primer, so it is very tough. The "houshould" primer seem to be just as hard as the wash primer. Zinc oxide and some orthophosphate?? seems to be the active anticorrosive ingredients in both.

One major difference is that the wash primer has a smoother and more shiny surface, and the coating is thinner (the last thing could be me sprying).

Priming solved and HS-409

HS-409 flange strips are filed and ready for drilling. I will postpone most other work untill monday when my tech counselor takes a visit to show me how to operate the vareous tools for best results, and how to prime the parts.

The priming headache has finally been solved. After a long conversation with my tech counselor on the phone I have decided to follow his advice for all internal parts:

• All parts will be alodined.
• Zinc chromate will be sprayed on from cans.
• MEK will be used to clean the parts.

This process is, according to my tech counselor, easy and a lot less messy than two component mixing and spraying. This is the method he uses when fixing damaged airplanes and restoring warbirds, and the corrosion protection is well documented through years of experience.