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RV-3B Dave's in Colorado

It's a fairly trivial bit of work, but I put the cowl back on for some checks and adjustments yesterday. I identified some areas to work. Like I said, trivial -- but the first bit of work on it since they hacked into me. And the week included two of the regular activities that I'd previously had. So I call it "progress."

However, it's quite clear that there's more recovery ahead, at a minimum.

Dave
 
Sorry, yet another post with no photos.

Here’s what’s been going in. As I continue to recover, my recovery progress is steady but slow, slower than I like. Today happened to be an unusually good day in many respects and I was able to work on this kit plane well over three hours. First time in a long time for that.

If I’m fortunate enough to get more such days, I’ll take ‘em.

Since the cowl tool had been sent back (it centered on the crankshaft and held Wirejock’s centering disk; I thought I was done with it), I used the centering disk as an alignment reference and found that the cowl was roughly a quarter inch off center laterally and about 3/32” off center vertically. At this stage, the top and bottom cowl are held together on the sides with screws and nutplates. The nutplates are installed but I’m using clecos instead of the screws.

The aft edge is quarter-turn fasteners and nutplates, with the quarter-turn fasteners along the top and lower sides and the nutplates along the cheeks. I had been using clecos at both the nutplates and the quarter-turn fastener locations for convenience.

The turtledeck between the panel and the firewall, which is removable on an RV-3B, was off.

The first step was to put the turtledeck back on. Done. I didn’t expect that this would affect the cowl position but I wanted to be certain. And sure enough it didn’t.

Then I unclecoed the entire aft edge. This left the top and bottom sides attached to each other, giving me a cowl which was floating on the firewall and baffle seals. I clecoed the front of it to the alignment disk and found that indeed, I could move the centering of the cowl around as I pleased. I checked with my mentor and he’s returning the cowl tool. That will let me nail down the cowl position, hopefully better this time, and redrill the firewall attachment holes.

At least conceptually, this problem is solved.

While I was at it, I tweaked the gaps between the top and bottom cowl halves a bit and filled one or two holes. Small stuff.

Dave
 
Here I am back again.

The cowl tool is working out just fine but this 2-day job is dragging; I haven't been working on the airplane. I got the cowl assembled and back on and found that the aft edge of the lower cowl needed trimming. I spent much of today doing that: mark where needed, remove, trim, install, repeat. But getting fairly close.

I've been using a bungee across the top of the engine mounts and down to two clips on the lower cowl to help support it while doing the removal/reinstallation. Here's a very poor photo, showing the bungee, the fitting and the ignition leads which are presently unconnected.

Cowl Support.JPG


Here's a shot of the left-hand fitting:

Cowl Support Fitting.JPG


On a different topic, my mentor called today with some comments about the exhaust hanger. The Vetterman exhaust came with the standard hose and tube arrangement, and the instructions said to attach it to this bar (the blue bar between the exhaust pipes). We discussed different approaches. Since I'd like to prevent vertical motion of the exhaust at this point, I'll have to build something with that in mind. It's still somewhat off in the future. I'll decide then if I want to connect it to the airframe of the engine; both appear possible, although hoses might get in the way.

Exhaust Hanger Brace S.jpeg


Dave
 
Here I am back again.

The cowl tool is working out just fine but this 2-day job is dragging; I haven't been working on the airplane. I got the cowl assembled and back on and found that the aft edge of the lower cowl needed trimming. I spent much of today doing that: mark where needed, remove, trim, install, repeat. But getting fairly close.

I've been using a bungee across the top of the engine mounts and down to two clips on the lower cowl to help support it while doing the removal/reinstallation. Here's a very poor photo, showing the bungee, the fitting and the ignition leads which are presently unconnected.

View attachment 58712

Here's a shot of the left-hand fitting:

View attachment 58713

On a different topic, my mentor called today with some comments about the exhaust hanger. The Vetterman exhaust came with the standard hose and tube arrangement, and the instructions said to attach it to this bar (the blue bar between the exhaust pipes). We discussed different approaches. Since I'd like to prevent vertical motion of the exhaust at this point, I'll have to build something with that in mind. It's still somewhat off in the future. I'll decide then if I want to connect it to the airframe of the engine; both appear possible, although hoses might get in the way.

View attachment 58714

Dave
It's good to see you back and pushing on with the build!

The bar on the exhaust looks like it would need to be beefed up or replaced with an angle if the intent is perhaps to suspend it from in between the tail pipes?
 
Thanks for the comment!

At this point all I've settled on is to attach the upper end of whatever the connection turns out to be to engine bolts. What's shown in the photo is straight out of the instructions that came with the Vetterman exhaust.

Dave
 
I got a reasonable insurance quote for my C180 and since I’m getting a few years on and have definitely passed age 75, asked about possibly insuring other kinds of planes. The agent told me that with some aircraft, it would be a matter of the underwriter’s being familiar with the make and model, as well as my own experience. She then mentioned one client, an 85 year old pilot with a C185 who downsized to an RV-4. She said that the pilot easily got insurance because the plane was smaller, less expensive and also a tailwheel type.

That’s when I told her that I was building the RV-3B. She took it well.

Incidentally, the company is BWI, not Gallagher.

The cowling’s Mil-Spec quarter-turn fasteners are installed now. Still need to add the various locking elements. These quarter-turn fasteners are equivalent to Skybolts, the chief differences being that I had to make my own mounting strips and Mil-Spec seems to be out of business now. I started with an RV-4 kit for these but didn’t use them on the sides, deciding instead to use nutplates and screws. I have a number of spares now in case of an issue. I inventoried the parts and there’s plenty left for the sides, I I decide to change to them there.

Making my own mounting strips for the quarter-turn fasteners was a good thing. Mine are more compact than Skybolts and lighter, both plusses for this little RV-3B. On the sides, I laid up some glass to make glass flanges.

Up to now I’d been using clecos in the screw holes. Today I drilled them out to #19 for the #8 screws. I used a #19 reamer in the #30 holes and this worked perfectly. I got smooth accurate holes.

When I tried inserting the screws, I learned that two of the #8 nutplates had mysteriously shrunk down to #6. Probably I’d gotten them mixed up in the bins years ago. That gave me some practice removing rivets and installing new ones.

With AN525-7 screws and thin nylon washers, the cowl is finally secure. It lines up nicely with the cowl tool off, and I’m ready to move on. There’s some glasswork still needed before finishing, though.

Looking at these photos, I realized that I’d forgotten to install the nutplates and final drill for the front center attachments. Please let me know what else I missed! And yes, I added them today.

Dave

Cowl Fasteners RH S.JPG



Cowl Fasteners Front S.jpeg
 

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Nice Dave!
Re the slight off center, my humble guess is that if the spinner is +/- centred on the cowl all will be good. Looks like the recess ape is not entered on the actual hole anyway ;)

PS
Nice to see you using the same tool trolley as my beloved uses for her knitting gear :cool:
 
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