Fuselage « Matt's RV-7 Project

Archive for the ‘Fuselage’ Category

Finished ELT door

Wednesday, April 4th, 2007

Okay, new plan. I could have made the Hartwell latches work and look okayish, but then I found these Camloc pushbutton latches. They are the same ones that are used to hold shut the oil filler door on a lot of certified aircraft, which normally makes them expensive – I think they are something like $36 apiece from ACS. Thank goodness, though, for the local aircraft surplus place, where they can be had for five bucks each. At that price I couldn't resist, so I picked up a handful to use for little projects like this. It's way easier to make a round hole for one of these guys than to file out the odd-shaped square hole for a Hartwell latch.

I had to build a new door to fit the new latches, but that was no big deal. I had plenty of extra scrap 0.032" from Airparts laying around anyway. This new door actually fits a lot better along the hinge area, which is a bonus.

I don't really know why I primed all these pieces. Superstition, probably.

Here's the finished product after riveting. I used some scrap 0.063" angle to make stiffeners at the fore and aft ends. The hinge pin has a bend in the end, and is inserted in such a way that it's prevented from backing out by the F-727L baggage floor rib. Simple as can be.

And here it is with the baggage floor screwed in place in the fuselage. It seems plenty strong enough with the stiffeners in there. It's also pretty easy to get the ELT in and out.

I couldn't tell how much "grab" the latches had until everything was installed for good, because it was too floppy to tell when it was just clecoed together on the bench. It turned out that the door had a little bit of rattle to it, so I riveted in some 0.032" striker plate thingies to give the latches something extra to hang on to. Now the door clicks shut and doesn't move.

This is what it looks like all buttoned up. With the carpet on top you won't even know it's there, but it's nice to know that I'll be able to get to the ELT in a hurry if I need it, and without needing any tools.

What a mess. Time to clean the workshop.

Posted in Fuselage |

Canopy work aborted

Saturday, March 31st, 2007

After putting some protective tape over the end of the slider frame latch tube, I flipped the canopy over and laid the frame inside.

The goal is to get the frame aligned on the previously marked centerline, in the fore-aft location that results in the best fit along the center spine tube. Then you mark the location of the latch tube and drill a 5/8" hole. I got as far as marking the hole location, but the temperature didn't get up nearly as high as I thought it would, so I had to give up on drilling/trimming the canopy for another day. Bah.

In an effort to find something else to do, I dug up the subpanel pieces, dimpled the top rib flanges, and clecoed the whole works into the fuselage.

Then I deburred the forward top skin, which I hadn't yet bothered to do. I dimpled where I could reach along the edges, leaving the holes along the firewall undimpled for now – the cowling attach hinges still need to be match-drilled there, much further down the road. Then I packed up the skin and drove over to John's to use my DRDT to dimple the rest of the skin. Not a very efficient use of building time, but it felt like a good day to spend a couple hours driving.

Somewhere in there I did some more filler work on the left horizontal stabilizer tip fairing. I've had this clamp for at least ten years and I'm pretty sure this is the first time I've ever used it.

Also, I stopped at Lowe's and tried to buy a new belt sander, but they were out. Bah.

Posted in Canopy, Empennage, Fuselage, Tip fairings |

Marked canopy centerline

Thursday, March 29th, 2007

You're supposed to draw a centerline on the canopy before you start fitting the plexiglass and slider frame together. I measured and marked center points on the front and rear canopy edges and stretched a piece of fishing line between them.

However, I didn't have a great way to make sure the string was centered as it went up and over the hump in the middle of the canopy. So, as is my way, I totally overengineered the problem by deploying a laser. I made this lashed up rig and duct taped my shiny new laser level to it in such a way that it projected a beam across the entire top of the canopy.

Here is the laser in action. For twenty-five bucks how can you go wrong? I love new tools. It took a bit of fiddling to get the beam straight and normal to the canopy surface – actually the reflection of the beam off the canopy and onto the wall made it pretty easy to figure out which way to go in order to hit it straight on.

It was hard to get a good picture, but basically all I did was nudge the string until it sat right under the beam, then drew a sharpie line along the string. Simple.

The finished product. The line is actually pretty wavy because I was freehanding it and it's drawn on the wrinkly protective film, but all that matters is that it's located on the real centerline of the canopy.

I also spent some more time bending and tweaking the canopy frame. I talked to Van's on the phone this morning and was told that as long as the frame is at least 1/16" in from the fuselage sides, you can shim the canopy skirts however you need. I'm 1/16"-1/8" everywhere except the rear corners, where I can't come in anymore without fouling the frame on the aft top skin when the canopy opens. It seems like I should be able to make the aft skirts bridge that gap, though.

Posted in Canopy |

Misc stuff

Sunday, March 25th, 2007

I spent the whole day in the garage but didn't take many pictures. I guess I didn't actually get all that much accomplished – mostly I puttered and cleaned up the garage. It was great to be outside in the nice weather though.

One of the pre-tail-mounting chores I've been meaning to do is drilling the holes for the strobe and nav light wires that will go through the vertical stabilizer spar into the rudder. I picked the same location as Dan for much the same reasons – with the taildragger there aren't many other good choices for where to run these wires. I drilled a 5/16" hole for the strobe cable and a 3/16" hole for the nav light wires. Both holes are a little oversized so I can use a few layers of shrink tubing and some RTV to protect the wires from chafing.

Another day, another round of filling and sanding empennage fairings. I'm just doing a little bit every work session, fitting the glass work in between other tasks that are more fun.

I rearranged the garage a bit, and made a little table out of a sheet of plywood and a couple sawhorses. This is where the canopy is going to sit while I work on it. Yes, I've decided to work on the canopy some more before I put the airplane on the gear and mount the engine. Matthew convinced me that it'll be easier to get to it while it's down low and not high up on the wheels. Plus it seems to be warm enough these days to start thinking about working with plexiglass again.

I got out the canopy frame to make sure it still fits – yep:

Posted in Canopy, Empennage, Tip fairings, Vertical Stabilizer |

Started removing the tail

Sunday, February 11th, 2007

I decided that I'd better get the tail permanently mounted before the engine arrives, since without the weight of tail back there the engine will tip the airplane over. But before I can put it on for good, I need to take it off once more in order to finish up a few chores. Tonight I got as far as removing the vertical stabilizer.

I squeezed the remaining rivets on the rudder stops that were previously blocked by the VS spar. I also smoothed out a few scratches in the aft bulkhead that were a result of the initial stabilizer fitting. Looks like the primer dripped – doh.

I attached the nutplates for the fairing to the vertical stabilizer:

…and one to the fuselage just in front of the tail:

Posted in Empennage, Fuselage |