Archive for November, 2011

Preparing to Rivet Outboard Bottom Skin – 1 hr

November 30, 2011 Leave a comment

Wednesday Nov 30, 2011

Tonight I only had a little time available so I primed the surface of the inboard skin that lies under the outboard skin. I taped off the area to be primed then roughed up the surface with scotchbrite. Next I cleaned the surface well with MEK.

I brushed a coat of Ekoprime on the surface. Brushing is not as uniform as spraying but for this small area I’m not willing to set up the spray gun, especially since this surface will be covered by the outboard skin.

As that started to dry I modified two AN fittings for the fuel vent lines. To remove the threads I put the fitting in my drill press and just filed the threads off using a file as the part spun in the chuck. Then I cut off the end at about a 45 degree angle and sanded it smooth on the belt sander. Here is a photo comparing a modified fitting with an unmodified one. Now apparently I need to get some screen material to bond to the end to keep bugs out.

Categories: Skins, Wings

Finished Left Inboard Bottom Skin – 1.5 hrs

November 29, 2011 Leave a comment

Tuesday Nov 29, 2011

Scott came by after work this evening and helped me bang out the remaining rivets on the left inboard bottom skin. Yes, the jigged-up bucking bar I made last night helped a bit. Still not what I would call easy, but better than before. Here is a “candid” shot of Scott inspecting rivets.

And here is just a victory shot of the “finished” inboard skin. The last two rows will be riveted in overlap with the outboard skin. Oh, and I also have to rivet the skin to the flap brace with the flap hinge but that will be a piece of cake compared to the interior rivets.

Categories: Skins, Wings

Making Tool Adjustments – 1 hr

November 28, 2011 Leave a comment

Monday Nov 28, 2011

I did not have a rivet partner tonight and I didn’t really have much time anyway so I spent it thinking about how I might make this riveting process a little easier. I decided to modify my tool slightly to help me align the bucking bar in those blind situations along the aft spar. Here is what I came up with.

Basically the wood pieces act as a handle and a guide. I used the longer piece while riveting yesterday but I needed something to help me get the head of the bar flush with the rivet. Reaching in blind it is easy to get the bar tilted and drive the rivet unevenly. The triangular block gives me a guide along the aft spar to push the bar against to make the head flush in at least one axis. It’s still blind but if I can reach the rivet head using the handle as an extension and push the block up against the spar flush I have a better chance of getting it aligned right. I hope I can try it tomorrow night.

Categories: Skins, Wings

More Progress on Wing Bottom Skin Riveting – 5 hrs

November 27, 2011 Leave a comment

Sunday Nov 27, 2011

My best rivet partner (Denise) is out of commission for a while because she broke her wrist and bruised some ribs in a bicycle accident so my friend Scott came over today and helped me make more progress riveting the bottom inboard skin on the left wing. Many of these rivets are very tough to reach. We spent about 3.5 hours and only made it half way through the fifth rib. If you click on the picture to blow it up you can probably count the rivets we installed. That weird shadow on the wing is from my Wagner house painter which is hanging from the ceiling above the wing (I bounced the flash off the ceiling). I keep thinking there must be an easier way to do this riveting but I can’t come up with one. I don’t see how anyone could do this solo. Is there a secret riveting order I could follow to get better access? Vans instructions are too vague on this.

Other than that I started making the fuel line that goes between the fuel valve and the pump this morning. The first bend I made with my tubing bender through about 150 degrees. The picture below shows the first bend. Those other fittings are for the fuel tank vents which I plan to work on next. It became clear that I will not be able to use the Imperial bender for all the plumbing bends so I ordered a set of those coil spring benders that you slide over the tube to prevent it from collapsing. Avery Tools had a Black Friday weekend deal with 15% off and $1 shipping so I took advantage of that to order a stainless steel hot air box for the firewall and get some more Snap Socs (used to reduce the risk of smiles on universal head rivets).

Categories: Skins, Wings

Started Riveting Bottom Skins, Left Wing – 5 hrs

November 26, 2011 Leave a comment

Saturday Nov 26, 2011

Before hitting the sack last night I was thinking about how I had routed the pitot heater wires yesterday and it occurred to me that I forgot to twist the power wires. A friend who is an electrical engineer told me that twisting the wires was one of the most effective ways of minimizing the electromagnetic coupling between wires. If there is any RF noise on these wires twisting them will minimize the radiation to/from other wires such as antennae and strobe lights. So first thing this morning I pulled the red/black wires back out and twisted them together as a pair, then ran them back through the wing. You can see the result in this picture. There’s no way I’ll ever know how much this helps but if I didn’t do it and I have electromagnetic noise issues later I would kick myself.

After that I torqued a few more bolts in the bellcrank area and applied torque seal. I mixed up a small batch of ProSeal and applied a small amount to the electrical conduit at each of the wing ribs. This is to keep the ribs from cutting through the conduit over time due to vibration. Then I spent about two hours cleaning off the work bench and the area around it before moving the left wing onto the bench to install the bottom skins. The shop really needed some cleaning and it is much more pleasant to work in now. Here is the wing moved into position for skin riveting.

I did the first few rivets solo along the rear spar in the first three bays. I taped the tungsten bucking bar to a piece of wood to give me a better reach into the wing.

After that I got some help from one of my daughters to complete the first three ribs in the wing walk area. This is one of the toughest parts of the project so far. I hate bucking rivets when I can’t get eyes directly on the shop head and most of these rivets are blind and the hand positions are awkward at best. But like Bruce Swayze said on his web site, you just focus on one rivet at a time and keep plugging away. This fourth row looks like it will be a challenge as well as the remaining rivets on the aft spar.

With the first three ribs completed I shifted from bucking from the inboard end to the outboard side. I used a piece of rope attached to the garage door track to lift up the outboard edge of the skin. I seems to work better with one person focused on bucking and one shooting the gun without having to worry about holding the skin up. I’m being cautious here because I don’t want a kink in this skin.

Categories: Skins, Wings

Wired Up Pitot Heater, Preping Left Wing for Closing – 4.5 hrs

November 25, 2011 Leave a comment

Friday Nov 25, 2011

A long time ago I “finished” the wings without riveting the bottom skins because I was uncertain which EFIS I was going to install and which autopilot servos I would use, one of which installs in the wing. Well the time has come to mate the wings to the fuselage and the bottom skins need to be on for that so I need to wrap up the wing wiring and close’em up.

So today I finalized my planning for wiring in the wings and ordered wire and connectors from SteinAir for the Dynon autopilot servo. That will take a few days to arrive but in the mean time I could work on the left wing and the pitot heater wiring which I also left incomplete last winter. Here is what I came up with for routing. I installed a 3-pin Molex connector for the heater module and ran those wires down the wing to the root. I also looped the heater wires around and tagged them down to a rib using tie bases. It is pretty clean and there is plenty of clearance to the bellcrank.

Here is a view from the top so you can see the wiring routing better.

This next photo is the pitot tube and the plumbing routing.

I also decided to dimple all the holes in the bulkheads for the upper aft skins which I probably should have done weeks ago. So I took the upper skins off again.

And while I had such good access I finished installing the clips for the static line routing. These are now riveted in place. I left about 6 extra inches of static line tube to make sure I don’t come up short later.

And for fun I decided to cleco on the ribs that support the instrument panel. This is just checking things out. They will come back off again tonight.

Miscellaneous Chores – 2 hrs

November 24, 2011 Leave a comment

Thursday Nov 24, 2011

Happy Thanksgiving! This morning I was able to get out into the garage early for a couple of hours before the activity started to get ready for our Thanksgiving get-together. I was hoping I could quickly install safety wire on the roll servo motor bolts but it took me five tries to get it good enough to be satisfied with. This one was tricky. It’s still not perfect but I am satisfied it will do the job.

Then I made a little clip to support the Tee in the static line on the F-708 bulkhead.┬áThis will keep the T from working it’s way loose from the static line under vibration. I made it from .020 thick Alclad sheet and secured it to the bulkhead with one LP4-3 rivet. The screw and the lock nut came with the Tee in the SafeAir1 kit.

Then I made several more clips to hold the static line to the back of the F-706 bulkhead in route to the ADAHRS unit. Here you can see two of the clips installed with clecos. I will rivet the clips later with flush head rivets on the forward side of the bulkhead. I stopped here because I am uncertain about the routing from here. I will either route it down the center rib with the pitot and AOA lines or I will route it along the nearest J-stringer.

Finally I installed a piece of plastic conduit in the aft fuselage through which I plan to route the electrical wiring to the tail; namely the strobe on the rudder. This view is from the F-706 to the F-707 bulkhead.

This is from the F-708 to F-710 bulkhead.