Dave’s RV-7A Building Log

The forward fuselage has a lot of little parts that all need some tweaking. It’s tedious, but I can see the light at the end of the tunnel.

Next step was to fit the F-7101 gear attach webs. I used the Scotch-brite wheel to file a little off the top edge and then rounded the top and bottom edges so they would nest in the lower longeron and side stiffener.

Once I was happy with the fit, it was time for drilling. In order to get the web to sit flat, I had to remove the clecos from the aft half of the aux longeron. I put rivets in the holes to make sure the stiffener and skin remained lined up. I then drilled the F-7101 to the lower longeron, the F-704 bulkhead, and the aux longeron. I also drilled the skin to the F-902 bulkhead.

The instructions next say to fit the upper and lower tab of the F-902 to the longerons. The top tab needed a little bit of sideways tweaking so that it would sit flat against the longer. The plans then have a detail of drilling the lower longeron. Well, I got confused (again) since the fuselage is upside down and drilled the top tab. I went back and drilled the lower tab as well. I’m not sure if the top tab really needs to be drilled. It’s not clear. At this point, it doesn’t hurt.

I next started fabricating the parts for the fuel tank attach point, F-796B, C, and D. Up until this point, whenever parts needed to be fabricated from sheet, there was always a piece that was exactly the right size or slightly oversized. I hunted around for quite a while trying to organize the remaining sheet pieces and figure out what part Van’s had intended them to be used for. It would sure be nice if the inventory sheet called out that info. I finally decided that there was no perfect piece of sheet, so I cut up some pieces I hope are spare material.

It took just a little more coaxing to get the F-684 gussets fitted. Putting in another slight bend where the gussets hit the firewall angle is the key. I then drilled the gussets to the firewall angle by peeling back the side skin. And finally I re-clecoed the side skin and drilled through the side skin, aux longeron, firewall bracket, and gusset.

Next I started fitting the F-902 bulkheads. It’s not much of a bulkhead compared to the others. It’s just two side pieces. I had to file the lower slot slightly and do some slight flange bending and fluting, but otherwise it fit nicely.

I put in some serious hours on the project today. I first worked on the angle clips that hold the forward skin stiffeners to the firewall. I clamped the angle clips to the stiffeners and then removed them both and drilled and clecoed them together. Then I put the assembly back in and drilled the angle clips to the firewall angle. Worked pretty good.

I then moved on to the lower longerons. The replacement angle arrived last week, so I was able to cut these to length and cut back one leg of the angle at the forward end. I then trial fitted them and put a slight twist in the angle. Once I was satisfied the fit was good, I drilled the bolt holes through the lower longeron and into the firewall bracket. I debated about whether to put the lower skin back on and drill the rest of the lower longeron, but decided to wait until I had the other forward parts in place. It’s much easier messing around in the forward fuselage area with the bottom skin off.

I next attacked the F-684 gussets. The plans have you cut out an odd shaped area, make two bends, and drill multiple holes. Doing all of that took 2 hours for the two of them. Very time consuming. It would sure be nice to have this part pre-punched. After all of that fiddling around, they did not fit well. I had to file away more of the cut out area to make the gusset align with the bottom of the skin stiffener and 1/8″ back from the firewall. Once that was fitting better, the bends were not working well. That’s when I decided to call it quits. Now, after looking on Matthew Brandes’ site, I see I am not alone. I was thinking that one additional bend would help things align better, and that’s exactly what Matthew did.

I cut the holes in the bottom forward skin for the tri-gear legs. Also enlarged the holes for the brake lines.

Fitted the auxiliary longerons and forward skin stiffeners and drilled them to the side skins. These all had to be shortened about 1/8 to 1/4″ and angled on the ends. I also fabricated the angle clips for the stiffeners, but didn’t drill them yet. I read on someone’s site that it’s easier not to drill the angle clips from the plans, but to wait until later. That does appear to be true.

Did a little bit of trial fitting of the forward skin stiffeners and auxiliary longerons.

I started off measuring everything on the firewall again and then finally drilled the two holes on either side of the bottom of the firewall to lock it in place. I then fumbled around with the fit of the upper bracket in the longeron. It just wasn’t fitting well. I won’t detail all of the iterations, but I ended up trimming the longeron back another 1/8″ because it was interfering with the bracket, and then clamped it together with a piece of 2×2 nested inside the bracket to give a better clamping surface.

Before drilling, I made the F-704L straps as a break from the firewall fitting and had dinner. After dinner and a bunch more measuring, I went for it. I drilled up (or downward relative to the plane) on both sides of the firewall. I looked ahead in the instructions and didn’t see any mention of when the bottom flange should be drilled, so I went ahead and drilled it along with the bottom angle. And then after more deliberation, I finally drilled the longerons to the upper firewall brackets. I spent more time measuring and examining than anything else, but I’d rather not mess up this part. It turned out great.

Drilled the other longeron up to the F-704. There are a ton of holes in these longerons. There’s going to be a lot of deburring and countersinking coming up. I then trimmed the longerons to 3/4″ short of the front edge of the side skin and drilled the longerons all the way forward. And then the step I’ve been working toward, I clamped the firewall and forward bottom skin onto the fuselage. The thing is really looking cool now. Makes a nice Christmas present to myself.

Drilled one longeron to the right side skin up to the F-704.

I attached the corner rib to F-705 strip that I previously fabricated and drilled the arm rests to the side skins.

Removed the side skins. Attached the other half of the F-704 and secured it with the wood spacers and bolts. I had trouble getting one of the bolts in all of the way. It’s the same area where I had trouble removing the bolts when I was riveting the F-704 together. I’ll have to look at it later when I have the parts disassembled. I might have tweaked one of the side supports.

Next I bent the corners of the side skins. They turned out pretty good, but I’ll do some more tweaking on them when I disassemble the beast. I didn’t get a tight enough angle at the forward corner.

I had a heck of a time getting the side skins to line up right around the F-706 and corner ribs. Adele and Julie were both helping me. I finally tried temporarily moving the sawhorse from under the F-704 to under the F-705 and bingo. Everything lined up. I clecoed the side skin to the F-706, then F-705, and then the F-704.

Before I had the side skins completely clecoed on, I was wondering if the longerons and skins were actually going to line up. It seemed that everything was slightly off. But after the skins went on, it looks great. The mark I made for the downward bend in the longeron aligns with the downward angle in the side skin, and the longeron follows the skin forward from there. I know everybody says this, but the longerons really lined up perfectly.

I only did a few time-consuming steps today. It’s better to take some extra time with things like bending the longerons and side skins. Those are not parts you want to re-order.

The fuselage is really solid and looks huge in my ever diminishing garage.