Category Archives: Mid Fuselage

Time: 8 Hours

Today I wanted to finish it the battery mount addition. I had the marks made on the mount support angles and I put the mount back into position to double check the marks were on target. Once I was satisfied I took the mount sides off so it was just the angles and the mount base bolted to them. This gave me room to take the whole structure to the drill press and drill the holes. I started with a #30 hole on al 8 holes. I then took the structure back to the fuselage and placed it into the correct position. I used the holes I just drilled as a guide and drilled down thru them and the fuselage structure underneath. I then moved the mount back to the drill press and enlarged the holes to 3/16″ with my reamer for the AN3 bolts that I will use. I grabbed the reamer and drilled the fuselage structure from the bottom up. Once I had those holes drilled I used my 3/16″ clecko’s to hold a -3 nutplate in place under the fuselage. I then used them as guides to drill a #40 hole up thru the nutplate and fuselage for the rivet attach holes. The two aft nutplates are one wing ones where the 2 rivets are on one side of the screw hole rather than one on each side.

In between those tasks I started the painting of the aft side skins, just the forward end, just aft of the second bulkhead gets paint as it is the rear baggage area.

I moved on to the countersinking of the angles of the gear tower and firewall where the nutplates will get riveted. I dimpled the 4 nutplate holes that are in the skin center.

Riveting all those holes took me 2 hours as it was a difficult place to rivet. I ended up using my tungsten bar on the flush side with a lot of downward pressure and my back rivet set from underneath. It worked pretty good except the aft inboard nutplate. I had a heck of a time getting them to sit and they are raised a slight bit. Won’t be a big deal as they are secure and the mount will cover them up. One mod I decided to do last night was to create a pocket of sorts in the right arm rest structure. Below the middle armrest between the two vertical bulkheads normally is just left open. Others have placed a piece of sheet metal around 4″ tall from the floor up to create a pocket between that sheet and the side skin and between the two bulkheads. To finish the look off I decided to add a small sheet filler from the armrest above this area going down towards the floor. You can see this top piece in the next photo.

I used my new 18″ metal brake to bend a 1/4″ 90° inward bend on this piece to give it some rigidity. I then used a piece of .040″ sheet to create the bottom piece and clamped it into place.

Once I was happy with the size and shape removed the hole armrest structure as one piece and laid out 3 holes on each side, using one existing hole. I then removed the bottom sheet and drilled the 5 holes to a #19 hole for #8 screws. I replace the whole structure back into place on the fuselage and placed the new pocket sheet in place and clamped it. That allowed me to match drill the new sheet with the holes I just drilled in the bulkheads.

The pocket sheet will have 6 nutplates on it that will secure it to the bulkheads. I will be able to bend the sheet slightly to remove it once the outside skin is riveted in place. I will also trim up the bottom as needed to get a good fit with the floor. While I was working on all this I also started the priming/riveting/painting of the battery mount support structure.

One last task I worked in today was to position a USB outlet that I got from Stein Air. My plan is to have a Ram Mount for an iPad/iPad Mini/iPhone on the right side of the rear roll bar as that will be right in front of the passenger. I wanted a power source close to that spot which would be the armrest aft bulkhead. So is mocked up that area with the cockpit rail in place to see how low I could go without the wires being seen thru the lightening holes in the roll bar supports bracket.

I clamps the USB to the area to see how it looked.

Once I was happy with the spot I marked it with a sharpie and removed that bulkhead to make the cuts.

I used the drill press to drill a couple holes followed by several small files get the opening just right. I clamped the USB back in place and marked for one of the screw holes and drill it to a #30. Once screwed into place I marked the second hole and drilled it. I attached the USB back to the bulkhead after rebuilding the structure on the fuselage to see how it looked.

Another very productive day in the Hangar and feel pretty good about the items I got done. I also touched up some primer on the aft tail bulkheads that got scratched during the initial fitting. That’s where I called it a night and cleaned up the shop so I could pull the truck in as there is a chance of freezing rain/snow tonight here in Chicago.

Time: 8 Hours

Like yesterday today I worked on more priming/painting with some fabricating work in between. The paint job wasn’t as good as an ABITL Finishing, but it was satisfactory. I had breakfast with the guys this morning and they stopped by to see my work and grade me! Good news is that they gave me the thumbs up on my overall work and Glenn looked at my battery mount and said it looked good. I had also asked him some other questions about my Andair fuel valve and its placement and that’s where I started today and figured I would work on the battery mount later since all I need to do is drill for the attach bolts. Before that started I grabbed one of the mid side skins and cleaned it so I could start the priming on it.

The fuel valve has 3 positions, left tank, right tank and off. The goal is to have the “off” position located in the aft or pointing towards the back of the aircraft. This would have the left pointing 45° to the left of center line and the right pointing 45° to the right. I also wanted to have the center post of the valve to be located on spot of the measurements of my buddies.

So I first sat down and did some thinking on how I wanted it to be attached to the mid side console. I decided that I would use 3/4″ x 3/4″ angle stretched between the inboard brace and the outboard mid longeron. In between those I would lay a piece of sheet that the valve would be screwed to. You have to worry about the thickness of the materials that you use as there is a cover plate that has the labeling on and it can only be 1/8″ max above the valve body. So my first goal was to find some scrap sheet that was close to the same thickness of the mid brace. I ran out to the airport as they have a scrap bin that they put old and new scraps in and was able to find a matching piece that was big enough. I used the template that Andair sends and made the required holes.

I then cut that sheet a little larger than I needed so that I could make the final size cuts later after the support angles were in place. I placed the angles where they were close and made some measurements from forward to aft. Once I had that measurements I was able to drill some #30 holes for thru the brace/longeron and the angles. On the outboard holes I enlarged them to a #19 for #8 screws. I made some likes on the angles and braces so I could be sure to line them up again. Then I removed the angles and added a single sided nutplate to the outboard ends.

The inboard ends I will leave at the #30 size until the skins and longerons are riveted for good as it will probably move the location of everything slightly. I can enlarge the holes then and if there is any misalignment it will be corrected with the larger drill bit. I then countersunk the 2 larger holes on the outboard ends for flush screws. Now I could screw those ends tight and clecko the inboard ends.

Now I had my forward to aft measurement all set I could now slide the plate inboard or outboard to get that measurement. Once I had that all set I marked and drilled 4 #30 holes in those spots. I then enlarged those to a #19 for the same flush screws.

I could now remove all the parts and drill for the 4 #8 nutplates that would be used to hold the plate on the angles. I countersunk the rivet holes for those nutplates and used the pneumatic squeezer to rivet them in place.

Now I could put everything back in place and clecko the valve in position.

That stuff took me hours to figure out and make al the fabrication, again I may not be as quick as others but it turned out perfect. In between all that work I finished priming and painting both the left and right mid skins, I picked those only because they were on top of the pile of skins I had waiting. I will keep those in my spare bedroom to help cure in the warm house for a few days.

I removed the battery mount and made some measurements for the 8 bolt holes, 4 on each side, for the work tomorrow.

Another great weekend in the Hangar and I always feel really good after spending so much time getting to work on the plane. I cleaned up shop and called it a night.