Tonight I finished riveting the left wing gap seals. I just have one rivet left (same as right side), where clearance is such that I need a pop rivet. After checking with Vans, I ordered some shorter Cherrymax rivets to get these two rivets done.
I could try bucking these rivets, but the rivet is so close to the angle on the bottom, I’m afraid I’ll end up bending the rivet and making a mess.
Tonight I started riveting the gap seals on the left wing. I was about to get all the rivets between the skin and the gap seals done tonight.
Today I riveted the right wing gap seals. This went quite well.
After clarifying with Vans their recommendation to use pop rivets for the flap gap seal, I started by cleaning the rear spar area, which is the “top” of the wing when sitting in the stand. A lot of dust, pollen, and shavings had gathered, so I took the time to blow it off with air then wipe it down with a damp cloth.
The I clecoed up the gap seals and started riveting. I squeezed all the rivets except those behind the already-installed bottom skin. For those I followed Van’s guidance and used Cherrymax and MSP-42 rivets. This was my first experience with Cherrymax, and I was surprised at how nicely they set. The countersunk rivet heads came. Out looking nice, and the squeezed manufactured heads looked good too. The only annoying thing was having the stems not breaking cleanly on a couple of the 42’s. I ended up filing them down which was time consuming.
Today I finished installing the access panel, installed an adel clamp for the pitot lines, and riveted on the end caps for the gap seals.
The access panel was straightforward; I riveted on the nutplates, then riveted it to the wing. I then spent time getting the panel itself to fit, I had to file about 1/32 off one edge. Then I screwed it on. I ran into a problem when the last screw’s head sheered off. I need to pick up an easy-out to remove this and try again. It sure why it sheered off, I don’t think I was using too much torque, just a handheld screw driver.
I took another pass through the plans looking for any jobs I missed on the wings, before I start closing them up. I came across the access panel in the forward skin of the left wing. This is to allow access to the stall warning system, (which I’m not planning to install). I have been thinking that this would be a great location for a camera. I’d like to have a camera that can see in front of the airplane, as there are some blind spots when taxing, and during takeoff and landing. Anyway, that can wait, for now I just need to install the access panel itself.
I deburred and dimpled the doubler plate and the access panel, then primed the doubler plate. Then I deburred and dimpled the rivet holes in the bottom skin. Once the primer is dry I can finish the job by attaching nutplates to the doubler, and then riveting the doubler to the wing.
Tonight I countersunk a fee holes on the rear wing spars, where the gap seals will flush rivet to the rear spar. it’s about 16 holes in total I think, so not a big job. What took more time was sorting through my countersink cages, swapping out the #30 countersink for a single-fluted bit, and then getting it configured to countersink to the correct depth on some scrap. The single flute is so much nicer than the more common three-fluted bits. It makes a very nice cut and just polishes the hole. It seems to be much easier to avoid chatter or deformation that can sometimes occur with the three-fluted bits.
After countersinking, I primed the holes and touched up the primer on a few other spots on the spar.
I didn’t take any pictures, but tonight I primed the gap seals for both wings. I used my standard primer the Stuart Systems EcoPoxy water-based epoxy primer. I am using high air pressure, lots of air, and minimal paint flow. It means I’m slowly building up layers, which makes for a better finish, I think. The downsides are that I’m often waiting for the compressor to catch up, so it’s slow, and paint particles get blown all over the garage. I have a fine layer of primer on many things in the garage. The high airflow seems to also dry the paint very quickly. So most of the paint particles being blown around are dry by the time they settle on things, and it’s more of a dust than a layer of paint.
Today I dimpled the gap fairings for both wings. The plans are not very detailed, but some common sense seems to be in order, I think I have dimpled the correct sides of the parts.
I also found a couple of steps of didn’t realize I needed to complete. I short row of countersinks in the wings, and the j-channel for the outboard bottom wing skins. The j-channel isn’t drilled, and is supposed to be match drilled using the spar. I’ll need to match drill it against the skin, which should be ok, but would have been easier before I dimpled it.
Two days ago I set up a tank test on the right wing tank. This time I carefully checked the tank fittings to ensure I had the correct amount of torque. I pumped a little pressure into the tank and left it for a couple of days. The water level in the manometer has tracked the temperature changes very closely, and I’m sure the tank is not leaking.
Tonight I primed the bottom skins for both wings. I have other parts ready to prime too, but I’m out of bench space, so will save that for tomorrow. It’s easy when only priming gone side of the parts, especially when they are flat and rectangular.
Priming the bottom wing skins
The last two nights I spent time deburring and dimpling the outboard bottom wing skins. Not much to report, just some tedious work getting this completed.
The right wing skin done and temporarily installed with a handful of clecos. This keeps the skin out of the way while doing the left skin.