October 31, 2002

Today I got email from another RV-7 builder who informed me that later in the process the longerons do come out for deburring and countersinking, etc., so I decided to put off priming them until then. Nothing left to do but to join up the center and aft fuselage...

But I ran into a little stumbling block when I realized that I needed another set of V-groove brackets for the third sawhorse. Check this out...this is ridiculous...when you buy these stupid sawhorses, you get them by the pair. Each pair comes with exactly two of these yellow plastic V-groove brackets. What good are two brackets with two sawhorses? Oh, well. I guess they're intended for use on only one sawhorse at a time. Whatever...anyway, the point is that I've got two pairs of sawhorses (four total), and only four of these freakin' plastic things. I need six!

So I called around and Home Depot (where I bought the sawhorses to begin with) claimed that they sell these plastic brackets separately. I trekked over there to find that not only do they not carry them separately, but they're out of stock on the sawhorses in general. Screwballs. Thanks a lot for telling me that on the phone. Losers.

So I called around, and nobody, literally nobody sells these brackets separately. And I'm not about to drive all around just to buy another pair of useless sawhorses just to get these freakin' brackets! Alright, I'll stop babbling. Sorry to go on about this, but it's so frustrating when you need something really simple and you can't get it. Word to the wise...DO NOT BUY THESE SAWHORSES. Yeah, they're stable...yeah, they support 1000 pounds...yeah, they fold up easily...but it's all but impossible to secure any type of board (2x4, 2x6, whatever) to the top without these brackets! So save yourself the time and just get some simple sawhorses.

Anyway, I decided to make my own brackets. Long story short, I made two of these suckers out of 3/4" plywood.

There you go. Works like a charm. Of course I used them on the aft-most sawhorse, the one that has to support the lowest load.

After all that, I put the longerons in place and clecoed down the skin along the bulkheads.

Here you can see the fit of the longeron in those slots in the bulkheads (that had to be enlarged to 1/8").

Next I put some clamps in strategic places to keep the longeron edge flush with the edge of the aft side skins.

When Jen got home, we lifted the center fuselage into place. This sucker is heavy! At least relative to everything else so far. Now let me try to save you some time and hassle here...listen up... The aft edge of the center fuselage consists of the bottom skin and the flanges of the baggage ribs. The aft fuselage flange (F-706 bulkhead flange and forward edge of the bottom skin) is supposed to get sandwiched in there in the center fuselage. More easily said than done. Since the clecos have to come out of the F-706, the F-706 tends to separate slightly from the aft fuselage bottom skin. Hard to describe, but you'll see what I mean. So with that separation, it spreads enough to make it a pain in the ass to get it into the little slot on the center fuselage. So I'll tell you what I did, and I'll tell you what I later realized is probably a better method.

Here's what I did...with the skin still clecoed through F-706, I wrapped duct tape around the front edge, trying to get it as tight as possible. Then I removed the clecos. The tape held the bulkhead flange to the skin just tight enough to let the center fuselage slip over it, more or less. With a little bit of coaxing and cursing, and with Jen lifting the tailcone slightly, I managed to get clecos in all of the holes. Phew!

So there you go...center fuselage is joined.

Now for the realization of how to do it better next time. First of all, I should say that Van's instructions mention that you're supposed to keep the seat and baggage skins clecoed in place to add stiffness to the center fuselage. Makes sense. But if the baggage skins were out of the way, you'd be able to reach up in there and coerce the F-706 flange into place so it would cooperate with the "sandwich" slip-in thing going on. That would make it so much easier to do this joining thing. With the baggage skins in place, as shown here, you've got zero access. So you might sacrifice a little bit of stiffness during the joining process in order to make the sandwiching easier. You can always cleco them back on once this is all joined. Just a thought.

Here's another view, for what it's worth.

And a view rom the front. Yeeha. Note: I don't claim that any of this is straight at this point. In fact, it doesn't even matter until the aft deck goes on. So don't bother looking at this with a critical eye for straightness.

Here's how the F-704 bulkhead sides rest on the sawhorse at first. The longerons just rest outside. For now...you'll see what happens in a second...

Didn't I already take this picture? Oh, well, the more the merrier.

Want a view from the rear? Yeah, I thought so.

Ok, time for a dinner break...ok, dinner's done. Time to cleco on the side skins. I started at the F-704 center section bulkhead. It's kind of hard to describe what happens here, but you need to lift the structure up about an inch and cleco the skin through the side doubler to the bulkhead...

...and the lifting is done so that this can happen. The skin rests on the sawhorse and the bulkhead kind of rests on the leg of the longeron. This is a really strange joint. I'm not sure I would have designed it this way, but Van did, so there you go. Until the skin gets drilled and clecoed to the longeron, this is kind of awkward, but it stays like this while everything is getting set up.

I actually have a fit problem on the aft end of the side skins. The problem is that the side skin is about 1/4" too low for the holes in the aft fuselage. Obviously the forward end of the aft fuselage is set too high, or possibly the center fuselage needs to be elevated slightly or tilted slightly downward. All this after I worked hard to level the sawhorses with each other! Before you comment on the fact that I have to remove the clecos from the bulkhead, yeah, don't bother...I put them back in to hold everything rigid while I work out this alignment issue.

I tried elevating the tailcone slightly with some plywood shims, but that didn't do it.

Ideally I need to lower the middle sawhorse slightly (can't do that). I raised both the front and back sawhorses, but that didn't do it either. So I'm pretty sure it has to do with the angle between the F-705 and F-706 bulkheads. I'll do some brainstorming to figure out a solution and work on it more tomorrow. It might be as simple as putting some support under the F-705 seat back bulkhead. We'll see.

On the other side of the coin, a few really good things came about today...first of all, the center fuselage is joined. That's a cool feeling. And it all fits great in the garage (I'm still excited about the new-found space). Also, the bends in the longerons couldn't be more perfect. The forward bends follow the contour of the skin perfectly. Not that I doubted myself, but it's a good feeling regardless.

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Dan Checkoway ()