Saturday, February 12, 2011

Nutplates Replaced

I finished drilling out and replacing those dreaded -08 nutplates with K1000-3s by noon. Again, having the right tool made this repair much easier than initially anticipated. Too avoid too much of a mess under the seat support floor covers, I put some duct tape over the back side of the nutplates before drilling them out. That way most of the chips were caught by the tape. The rest was vacuumed by attaching a flexible plastic hose to the muzzle of the shop vacuum. Pretty noisy (the plastic flex hose was acting as a very short organ pipe) but effective.
The new nutplates went in and my fingers were just long enough to get the aft nutplate caught by a cleco. Thanks to the dimpling the positioning was fairly easy.


The few scratches in the primer and some dirt on that tunnel side will disappear when I apply a bit more primer over it. The CCR264 installed without problem but I have to say I was very diligent about installing them. Getting these out by drilling if they start turning in their holes again would be nearly impossible.


Even though this issue took me a week a week to fix I cannot say it wasn't worth it! While I was working in the tunnel today I saw a few empty holes that made me wonder ....


This is the flaperon mixer bracket and checking with the plans after seeing this showed that I had also overlooked to rivet it completely to the tunnel rib. Hm, I wish I had kept more like a diary style log of that build day as it appears that I had outsourced this work to some cheap low quality company instead of doing it myself. I must have had a really bad day without even realizing what I was doing.
With the CQR (Close Quarter Riveter) this problem was quickly resolved, though.


After fixing all these issues I would have loved to finish section 21 by putting the screws in the tunnel but my helper wasn't there and so I had to postpone this last step. Just as well, as I later saw that the postman had delivered the dimpling kit I had ordered a few days ago that will allow me to install some nutplates in the belly skin above the landing gear tunnel where the plans said as much as 'OPTIONAL' - without explaining further. Inquiries with a few people and searching in usual and unusual blogs revealed that you really want some nutplates installed. They will hold the VHF antenna for the COM radio and while the initial installation is easy, it will get almost impossible to remove the screws holding the antenna once the landing gear is installed... . Unless you install nutplates, which then will turn this task into a very simple job of removing 4 screws.
So, there will be a little bit more work to be done to really finish section 21, which might just all happen tomorrow.

As I had a little time left before engaging in profane weekend activities with which ordinary non-airplane-building people usually spend their time, I went back to section 22 and finished the step of attaching the horizontal bulkhead on the firewall that builds the ledge. This required mixing some Proseal and I didn't want to do that at the end of the building session last time as it was getting late.


I mixed some of this stuff and kept some in the mixing cup while filling most of it into a syringe. I got a large amount of syringes to eventually fill the rivet head with epoxy filler to seal the head facing up from water getting into them. The mandrel is raw steel and will start to rust if this happens and besides this the paint job on filled rivets will look much nicer and last longer as the paint is quite stressed where it sags inside the little hole of the rivet head as it is not supported from underneath and water will sit in this little dent longer and not just run off.
I wanted to use the syringe to fill some of the holes on the bottom of the lower firewall where the flange attached to the corner skins. I think this will happen later but I knew I would have enough Proseal to spend it their now. I also filled the opening on the steps which I had skipped earlier. I picked up Dave's idea of applying masking tape over the opening after filling it with Proseal and turning it upside down. That way I don't have to fill the hole completely and should still get a nice finish. We'll see tomorrow how it turned out.
On the upper flange of the lower firewall I just smeared a thin layer of Proseal before putting the horizontal bulkhead in place. I used the stirring stick for that matter. It looks like the amount was about right as there wasn't too much sealant pressed out. neither on the front not inside.


Finally I was able to get that breathing mask off of my face, shower and enjoy the simple happiness of watching a movie with my wife. 'King's Speech' - I can very much recommend this one.

4 comments:

  1. What's the page number that shows the optional nutplates? That sounds like something I ought to go back and do.

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  2. It's 21-16. if you don't have the latest revision you can find it here:
    http://www.vansaircraft.com/pdf/revisions/RV-12/21-16.pdf

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  3. After looking at your post from today, I think I will have to wait until I put the fuselage on its side.

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  4. The fuselage got quite heavy now, so think ahead on which side you want to turn it onto when you do. The hole for the antenna is off center of the fuselage, more in the center of the passenger seat and depending on the height of the fuselage support you get better access for this work by turning the fuse one way or the other...

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