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RV-3B Dave's in Colorado

Main Ribs To The Front Spar

Starting with the right wing and using some bushings, I pilot-drilled the main ribs to the front spar. The first pass was through the web of the spar. Once that was done, I removed the ribs, drilled them to #30, and clecoed them to the spar.

With all of them clecoed, I used more bushings to pilot-drill for the 3/16 inch holes through the caps. Then I disassembled the ribs and drilled them out to the final size.

The next step was to remove all the ribs for deburring.

The left wing, shown here, is now ready for the first pass of pilot holes.

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If you look closely you'll see that the ribs have all been drilled for the plastic bushings for the lights and stall warner and pitot lines. It's pretty easy to do that when the ribs are off the spars, and harder when they're on. You don't need to know the specific brands and models of these things yet, just roughly how many wires and hoses to allow for. The wires, etc., will go in before skinning the wings.

The holes in the rear spar to the ribs are all drilled but haven't been dimpled yet. I learned that my pneumatic squeezer will indeed dimple the .040 rear spar. The blue parts in the background are the flap brace and aileron fairing. The aileron fairing is the W-724 substitute that Randy Lervold recommended. They're here so that I could see which holes needed dimpling. At this stage of the game, I'm not convinced that the W-724 is a significant time-changer for a standard-build kit. But on its outboard end, it's already trimmed correctly for the aileron hinge fittings, and that's a plus, especially since the plans don't mention that at all.

The drill bushings were straight from the local hardware store. These are simple brass tubes that nest in one another. The one on the left was used for the #30 web holes, and the set of longer ones was used for the 3/16 inch holes in the spar caps. The smallest tube takes a 3/12 inch bit, shown, but not a #40 bit.

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These have done a good job of protecting the front spar while drilling all those holes.

I keep them in a small parts ziplock bag in my drill drawer so I don't lose them. I hate losing things like that and I'm very good at it.

Dave
 
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Wings On Jig

Right now the wings are on the jig, and most of the nose ribs are mounted. Except for the tanks, there's one rib to go on either side.

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The inboard-most nose ribs are now being mounted.

And yes, the garage does have windows on three sides.

Dave
 
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Your garage is a real airplane factory, David. The process is different than assembling a pre punched kit, it is a genuine build and looks great.

Long live the -3!!
 
Caught Me By Surprise

I was following the manual, kind of chugging quietly along, and suddenly came upon a section called "Fitting The Wing Skins." And the next thing I needed wasn't some small piece of 3/4 angle, it was the one-piece top main wing skins.

So out to the hangar I went, and back home I drove, with two skins and the walkway doubler piece in the truck. They are now in the shop and I'm wondering how on earth I'll manage them all by myself.

That wing crate still has a number of things in it that I haven't touched yet, but it's definitely looking more empty than it had been.

Dave
 
RV-3B: More Think, Less Build

Thanks - gotta figure out just how to do this first. If the wing jig permitted having the wings horizontal, it would be a cinch, but it doesn't.

Looks like the first step will be to drill the skin holes that mate to the spar flange. I can drill the skin on the bench and use that to drill the flange. Then the rest should be straight-forward once I decide how to support the skin on the frame before drilling anything. I want to think the process through before committing to anything.

I made a simple edge-drilling jig. It's two pieces of 4130 plate, .093 thick and about 1.5" x 3" that make up the "bread" of the sandwich. The "filling" is a strip of .040 aluminum about 3" x 1/2" wide. I riveted these together with the aluminum on one side. Most of the space between the steel parts is empty. I drilled a #40 hole through both steel pieces that's 1/4" from the inside edge of the aluminum strip.

This gadget slips over the skin and lets me drill a hole a constant 1/4" distance from the edge. Or will once I start using it.

I used 4130 because I had the scrap on hand. The .040 aluminum is thick enough that it lets me keep the blue vinyl on the skin while I"m drilling. Making tools is a helpful way to think about how to build the airplane, and this tool is a general-purpose one.

And yes.... I acknowledge that my Whitney punch has a stop that would let me set this distance and simply punch these holes. I remembered that after I'd built this jig, sigh. I'll play with both and then decide which I want to use.

Dave
 
If you really want to work your wings horizontal, consider this type of fixture. Just a large bolt welded to heavy angle through a hole in the vertical square tubing. Each is easily leveled independently to ensure no twist in the spar:
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Here they are in action. Saved me from having to lay on the floor to rivet the skin to the rear spar:
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Working away on the wing skins. The top main skins are now drilled to the wing and have been removed so that I could drill the bottom skins to the wing. Between skins, I double-checked the twist and to the limits of my measuring tools, it's still zero.

I made a dumb goof on the bottom skins and you've got to remember that this is an RV-3B and it's not pre-punched. I merrily went along drilling the skins and the spar flange, figuring I'd sort out the inspection hole covers later.

Wrong!

The inspection hole covers have dedicated fastener holes in the spar flange and now I've got rivet holes there instead. I'll have to sort that out and figure out how to do it. In the meantime, I've been making the inspection hole doublers and that's reasonably straightforward. The photo shows the ones for the right wing. At the top is the pattern for the outboard left wing. It has a strange ear on one side because it'll also double the pitot tube hole in the skin.

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The outboard bottom skin is long enough for a double row of rivets at the splice. I had originally thought to use one row with 5/8" spacing (as shown in the plans) as it would be slightly lighter, and then realized that the double row and wider spacing would be smoother. Drag versus weight? In this case drag won the day.

Dave
 
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Now Leading...

Well, now I'm fitting the leading edges, anyway.

The main skins are drilled and clecoed, but not dimpled. The top and bottom skins are clecoed to the wing frame right now, and the leading edge skins have been drilled and clecoed to the top of the main spar.

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I've drilled the top flanges of the nose ribs and plan to back-drill the leading edge skin to these flanges once I've got the skins pressed down to the nose ribs.

Dave
 
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Not Exactly As I'd Intended

When I pressed the leading edges down on the frames, the leading edge radius looked too large. Starting with the right one, the aft one in the photo, I was able to correct that and the leading edge then fit very nicely on the ribs. I drilled and clecoed the bottom of that side.

Looking more closely, I found that in between the ribs, that there was a flat spot just aft of the leading edge radius on the top in between the ribs. Since I'd rebent the leading edge radius that was clearly my fault. I attempted to add some more curvature in those areas and didn't succeed. Scratch the right-hand leading edge skin.

A friend came over to help with the left one. He had some excellent suggestions but it appeared inescapable that I'd have to rebend that leading edge radius too. Well, I botched it, putting that bend slightly out of position. That scrapped that leading edge skin too. This wasn't going the way I'd hoped.

I ordered new parts and started the tanks in the meantime. I had been looking forward to the tanks anyway - maybe it comes from playing in the mud when I was a small child, but gooey things are sometimes fun, and I'd enjoyed using Pro-Seal before.

Here are the ribs on the right-hand baffle, just getting started. The left one is at the same stage.

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Dave
 
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Flood Clean-Up

I got hit less than a lot of folks and I'm pretty grateful for that. One of my friends lost everything, including an entire workshop with a lifetime's collection of tools.

Still, I've got a basement that's going to take some cleaning out, and the RV-3B project will be on hold while I do that. The RV-3B was not in the basement and was completely unaffected out in the garage.

At this point, the clean up is just a matter of labor and time, plus I get to practice my swearing.

I'll get back here when the project's underway again.

Dave
 
Cool Parts Found While Cleaning the Basement

I had more water damage than expected, and had to remove more things than anticipated. And of course there's a bit of mold correction and I've been replacing things that can get moldy with things that can't.

Only four inches of water and silt can sure make a mess!

One good outcome was that I found a can of assorted AN hydraulic tube fittings that I'd "lost" down there. This is definitely RV-3 related. Plus I found a perfectly good helicopter airspeed indicator that I'd forgotten about which covers the RV-3B speed range. It's calibrated in knots, and if I use it, that'll make the decision between mph and knots. Since my Cessna 180 uses mph I'm tempted that direction, but of course the rest of the world uses knots so that's tempting, too.

Which reminds me that one day, back when I had my Corsair F-27 trimaran sailboat I was buried in work with a laser equipment client, and took a brief break from that to see what was going on at the trimaran forum. Someone was using the letters "nm" and I couldn't understand why nanometers, a common (and very tiny) measurement for laser development, would be used in sailboat operation. Too much work, eh?

Another potentially useful finding was one of those control stick grips with many switches. For emphasis - far too many switches. Too many for a day VFR airplane. This too is tempting, though I don't know what I'd do with all that switchology. For example, there's the common trim hat button. My RV-3B will have mechanical trim. This thing might be overkill. I haven't weighed it but it's not light.

Anyway, I'm still plugging away down in the basement but things are now at the stage where I'm looking towards completion. I can see it but I'm not there yet.

Dave
 
Back To Building the Tanks

Looks like back when I was prepping my tank ribs, I drilled a vent hole on the inboard tank rib and then accidentally put that rib at the outboard end instead. Now I've got a nice hole that I've got to patch and a proper hole on the inboard rib to drill.

Yes, I'm back to work on the RV-3B after the flood. It's been about a month. I'm working on the tanks and I'd left all the parts where it was easy to resume. In the interim, I cleaned out my basement. That wasn't something I'd planned on doing all at once but the flood, which left about four inches of water down there, provided me with some motivation.

Today's job was fitting the fuel tank baffles and ribs and Z brackets to the wings. At the end of the day they are almost ready for fitting the tank skins, but still need the rib-to-rib spacing supports that will hold them straight.

You can see my extra hole on the left-most tank rib. This is the left wing. You can see a bit of the right wing in the background.

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At the L.O.E. fly-in, it looked like it might be a good idea to install a second set of tie-down fittings near the wingtips. The standard tie downs are about 11 feet apart, and with airport tie-downs being 25 to 35 feet, the ropes are too shallow an angle to the airplane of the ground. This will help fix that.

I made a quick analysis (my line of work before retiring) and decided that the RV-3B spar web and flanges are strong enough for that load, although I can't say there's a lot of excess strength there for this.

Dave
 
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The dimensions of the RV-3 do pose some interesting conundrums Dave - like tie-down ropes being too short (which is why we carry our own). Then again....I was talking to an Air Force Active Reserve mechanic yesterday (she was volunteer security at the airshow I was attending), and she allowed that the wingspan of the -3 would fit nicely inside a C-5A - with room to spare. That lead to the topic of an air launch..... :)
 
Looks like I was too hasty getting back to the RV-3B after the flood. Some friends are needing a lot of assistance and I've been helping out, which takes up my time. And unfortunately there's another time-taker on the near horizon, too.

BUT -- I put the finish kit on order and the rest of the sole-source items. With a little luck, they'll all be safely in the hangar soon along with the engine and the fuselage kit.

And, in the moments when I've got time, I've been fitting the tank skins to the tank ribs. Remember that this is a non-pre-punched kit. It's not a sure thing.

Dave
 
Right Hand Tank Skin Strapped Down

Recently, I’ve been having trouble getting the tank leading edge to lay fair. You can read about that in the RV-3 section, in a thread titled “Leading Edge Woes.” Here’s a photo of the affected area:

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I apologize for the quality of the arrow I drew to the flat area just aft of the leading edge bend, but if you can follow it, that’s where the flat area is.

The right-hand tank skin is strapped down at the moment. The aft top edge is positioned so it butts to the top main skin.

Those 1” squares of .063 overlap the tank skin and hold it in place. That was a good idea from “27 Years of the RVator.” One of our tool companies should produce those and sell packets of them since I'm getting tired of making them. (If you’re a tool company looking for a simple useful product like this, the #40 hole is 1/4” from an edge, and all edges must be smooth and rounded. If they're straight too, that's a bonus sign of good quality)

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I'm using the outboard skin to provide lateral positioning. As you can see, it's not strapped down.

Strapped like this, we can look at the inboard rib to see how it looks on the inside. Since I haven’t put in the access hole yet, we can’t see how any other ribs are fitting. But by feeling them from the outside, through the skin, they’re okay. The only area of concern is just immediately aft of the leading edge radius in between the ribs, as I've described.

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To me, it looks like except for that area of trouble, the top is basically okay. While there's some gapping on the bottom, once the top has been drilled and clecoed, I should be able to make that go away. And if I'm careful, I'll be able to get that small gap on the top near the front to disappear.

Before drilling, I'll pull the skin off and double-check everything, especially my notes for where the ribs actually are.

Dave
 
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Looking good Dave. I can imagine how difficult it is to get the skin-ribs to line up and then get drilled. Have fun!
 
Hey David - in your past picture, that little gap on the upper surface between the rib and the skin is exactly where if have slight depressions on our QB wings - that's about where the forward-most rivet sits. If you can work a shim in there, you might have a smoother wing.
 
Now that's darn good to know. Thanks! Actually, I wasn't sure if that was a mis-bent rib flange or it it was real.

And if you look very closely at the inboard edge of the skin right about in line with the upper forward notch (hate that word, as an old stress guy it's just not right) in the rib, you can see where the factory leading edge bend stops and the flat area of the skin starts. It only goes an inch or so. I hadn't noticed it on the photo before. Makes me wonder if it's an artifact of the rib after all - something to explore when I'm back home and working on it again.

Thanks again.

Incidentally, it was for the fun of sorting through these issues that I am building the slow-build RV-3B. Gotta say I'm getting my money's worth.

Dave
 
Incidentally, it was for the fun of sorting through these issues that I am building the slow-build RV-3B. Gotta say I'm getting my money's worth.

Dave

You're sick! ...says the guy building a slow build 10. :D Not the same ballpark, but definitely the same sport...
 
Santa Came AGAIN!

Second time in two years, I like the consistency. For the last event, refer back to post #31.

Here's Santa's sleigh and the green reindeer out in front of my hangar today:

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Once we opened the door and hauled the goodies to the back of the hangar I got this photo of the Finish Kit - that's the fuselage kit to the left, and the wing box in the far background against the wall:

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I've lately been ordering the sole-source items and this, the Vetterman exhaust and a few other things are on the list. Since I ordered a Todd's canopy, the canopy wasn't included as part of this finish kit. Neither was the spinner nor the tires. Why not the tires? Simply because I won't need them for at least a year and I can get them any time and they'll be fresh.

There is no FWF kit for the RV-3B, but I did include a few of the known needs, like the baffle kit and the FAB.

Initial impressions are that the fiberglass work is decent (don't know how it'll fit) and the kit for the baffles is new-style: pre-punched, trimmed, bent and with step-by-step instructions. Super!

Dave
 
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Pre Punched! Holy **** Dave, are you selling out!! haha!
I am finally back in Colorado for the holidays. I hope to get down to Denver to say hello to everyone.

I have just about settled on the Skyview for my panel. I really like what I read about how the GX3 autopilot is very nice, but the Skyview still looks like it fits me better.

Have fun and keep posting pictures of what real build is! Talk later.
 
Leading Edge Skins, Still

Both tanks are now clecoed and still in place. I haven't unclecoed them yet. Here's the right tank:

I8UpSp3.png


The baffle will get drilled after I remove the tanks from the wing. Didn't want to risk damaging the spar.

I've started on the outboard skins. Having the tank skins inboard lets me match them. Since the outboard ribs don't extend to the leading edge (they stop an inch aft) I made some wooden braces to prevent pulling the leading edge down too far.

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The vertical slot is to let me slip them over the threaded rod that hold the nose ribs in place. This way I can use one set on both wings.

Initially, I used the Howe Fittings and basically the same process I'd used on the tanks to hold the outboard skins in place. But no joy. For some reason, when I used them, the leading edge would consistently be about 1/2" below the leading edge of the tank skins. After a lot of head-scratching I determined that not using the Howe Fittings seems to work, and here's where I left the left outboard skin at close of shop tonight.

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I'll have to untape the Howe Fittings before proceeding. Duct tape - builder's friend.
 
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David,

I like your rib stiffeners! I'm going to copy that if/when I ever pick back up on my HRII project.
 
I'm now on the 3B wagon too..

You're sick! ...says the guy building a slow build 10. :D Not the same ballpark, but definitely the same sport...

Well Dave,

As you know, I've recently aquired a partially completed RV-3B kit, which I plan to work on alongside my 10 build. I guess whatever "sickness" you have is apparently catching...;)
 
I went back to the right-hand outboard skin and, using the Howe Fittings and a batten, got it to fit pretty well, so I went and drilled that skin to the ribs. These holes are drilled blind so I earned a few more gray beard hairs here.

Following that, I had the spice strips, that go between the tank and that outboard leading edge skin, in place and drilled to the ribs. I went ahead and drilled them to the tanks, then removed and deburred and dimpled them.

Here I'm trial-fitting a nutplate to the left one. Van's calls them "plate nuts" but as far as I know, no one else does. In addition to the cleco clamp, a #30 cleco does a nice job. Better, in fact, and that's what I'll use when I drill them, I think.

tXyzO3W.png


Dave
 
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Past Leading Edge Issue

Just wanted to mention here that I'm finally past the leading edge shape issues that I've had. Now I can move on with the wing. I've got a few related things, trimming edges, mostly, and then I'll be able to do something NEW for a change.

To David Howe - thanks again. Your advice was hugely helpful.

Dave
 
Light Weight Tank Stiffeners

The tank stiffeners on the RV-3B wing tanks are 3/4 x 3/4 x .032 angle. I'm now making the parts that go inside the left tank, starting with these. I made a set that's mostly stock (I beveled the upper corners) and they weighed 153 grams for the set. These are the top batch.

Then I made a set from .016 that I bent up, adding a short flange to the top. With this flange and in spite of the thinner material, these have the same stiffness as the stock version. These weigh 99.0 grams and are the bottom set.

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The difference is nearly 2 ounces per tank. Worth going after.

Dave
 
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More Tank Stiffeners

I made a second set, this time for the right tank. I've also deburred the right-hand tank ribs and baffle and made those little flapper valves that are shown on drawing 12A for the inverted system.

While my carbureted airplane won't have an inverted system, some RV owners have reported that the flapper valve helps when low on fuel in turbulence, so I added them. Also, it should be useful during slips. I'm putting them into both tanks.

Both tank skins are now drilled for the caps and the drains, too.

Dave
 
Flapper Valve

Thought that perhaps someone might like to see the flapper valve. This in the one for the right tank.

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The plans says to install it for the inverted fuel system, which I won't be installing. But this should be helpful in slips and turbulence.

Here's what the plans shows:

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and

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But the plans didn't include the tooling hole or the stiffening features embedded into the rib. That led me to making the hinge shape as I did. If I'd made the flap taller and moved the hinge higher, things would have been a lot easier, but I didn't think of that when I was doing it.

I also wanted to keep a bit clear of the bottom edge, and to avoid Pro-Sealing the valve, I'll tape it open when I seal the ribs to the skin. The valve is rounded simply because square corners contributed nothing except an attraction to the planer Earth. This is ever-so slightly lighter.

The final detail was how on earth could I prevent the pin from coming out? Turns out to be a no-brainer: with the bend end aft, the baffle will retain it. Of course the forward end needed to be long enough so it doesn't fall out then.

Worth mentioning is a tiny bit of philosophy.... One reason I'm making small weight-savings changes like this is just to keep in the habit of doing it. Perhaps if I do it often enough I'll have a light RV-3B.

Dave
 
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Oops And Go

Good news and some bad this time. The bad news first.

I scrapped the tanks just before sealing them. I made a mistake, the Mother Ship said it would be a relatively easy fix, I didn't care for the way the result turned out and decided to make new ones. Parts on order.

Okay.

Moving on.

Figured that this would be a good time to rivet up the outboard leading edge, but before I did that, I needed to work out the installation of the landing light and the stall warning vane in the left wing. You're probably thinking, "What do you mean, work it out? Get the Duckworks landing light mount like the rest of us, and install the Van's stall warning vane."

Well, this is an RV-3B and it's not entirely that simple. The Duckworks lens is a nice fit - thanks, Duckworks! - but the mounting plate is not. I figured out an alternative mounting approach. And the stall warning vane assembly is pretty nice. It even includes some pre-punched parts! But it's intended for the RV-7, -8 or -9 so some of the parts won't fit. And it needs an inspection hatch.

I saw a very nice RV-8A at the 2013 LOE fly-in that had the vane just inboard of the landing light lens. The pilot said it worked well and access was through the lens. It looked as if I could adapt that to this installation. I had to make a couple other tweaks, though, for ease of future access.

Here's the stall warning assembly and mount combined with the landing light mount support. Please note that this assembly was made without the fasteners getting tightened. I just assembled it to check the fitting up of the thing. I didn't tighten the fasteners because the tools were outside and it was cold today. I promise I will before it's permanent.

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And another view,

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The landing light mount itself is partly supported by this piece, but it's another assembly, this one composite. I was glad for that since I LIKE working with composites. Here's a bit of fiberglass I made for the mount.

tweqVRO.png


Pretty easy.

Back to the outboard leading edge, I'm gluing the carpet strips to the cradle pieces now.

Dave
 
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Stall Warner Installation

After needing to be out of town for a few weeks and then another short trip, I'm slowly getting back to it.

Right now I'm trying to find the place to cut the slot for the stall warning vane. This isn't part of the RV-3B kit, but I bought one from Van's. It's going into the outboard-most bay on the left leading edge, and with the leading edge now riveted but not attached to the spar, this is time to cut the slot.

I made a short straight strip of .032 aluminum to simulate a vane, so that I could move it in and out until it touches the leading edge. I still need to see if the bend in the vane (not shown) is inside the wing, right at the leading edge or ahead of the leading edge.

p9NzSzN.png


The keen observer might recognize that I made this one a mirror image of the way the stall warning kit is designed. This will permit access from the tip or from the as-yet-uncut landing light lens hole.

RV-3B: Not like the other kits.

Dave
 
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Nice Work!

I still want to see your landing light install. I haven't done mine yet. Still in head-scratchin' mode. ;)
 
Landing Light Mount

Here's the landing light mount. It's made of some unidirectional carbon fiber kite spars that I bought from IntoTheWind.com, which has a local store. I had to make the fiberglass tabs myself.

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The blue tape is to identify the outboard end as the mount isn't symmetric.

The mount with the light installed is easily removable through one of the lightening holes in the nose rib at the tip. Or the light itself could be removed through the lens in the leading edge if I didn't feel like removing the wingtip.

The mount itself weighs 33 grams. It replaces a Duckworks landing light mount which weighs 142 grams as-is, or 137 grams with the mounting cut-out cut.

tZ7p5HN.png


The Duckworks mount didn't actually fit all that well and replacing it saved me 104 grams or 3 2/3 ounces. Plus it was cheaper. Of course now I've got a couple Duckworks mounts for sale.

Dave
 
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The ends of the carbon rods will fit in bushings in the large holes in the outboard rib and in this rib.

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I've got to do some cutting in there for the landing light lens and the stall warner vane before I mount the light.

Since carbon and aluminum can corrode, the bushings isolate the two.

Dave
 
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The stall warning vane got its slot made and is now mounted, and the landing light hole has been made. The top lens mounting strip is riveted and although it's not shown in the photo, the bottom one is too.

sL4vpPG.png


That's not much to show for a month but this is my busy season.

I'm now fitting the lens.

Dave
 
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Landing Light, Lens and Stall Warning, Installed

First I had to change the mounting assembly around so that the Microsun landing light mounts from the back rather than the front - the big rib lightening hole on the left, after removing the wingtip, makes better access than the landing light lens.

I used a plastic hose clamp, visible at the upper left, for lateral restraint on the mount. There's one on the exterior, too.

S5NeORn.png


I tested the hardware: the stall warning switch works and so does the Microsun. That light is bright! And it's got a nice wide angle, perfect for my daytime VFR collision avoidance.

Be seen.

Dave
 
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Tie Down Fitting and Hole

One thing that had kind of bothered me was that according to the plans, there was a bit of a gap between the bottom skin and the tie down fitting. I decided to fix that.

Since I had a set of Cleaveland tie down fittings on hand, already threaded, this was a simple matter of matching the holes and doing a bit of trimming.

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The drill press quickly match-drilled the new part.

I used the band saw and cut the shape. I laid out the taper and cut that too. The 6 1/2 tpi wood blade cuts thick aluminum well, and the Vixen file smoothed it. Quick and easy, just a few minutes of work.

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The new one is half an ounce lighter, even though it's bigger. Worth doing.

What I didn't do is use these new tie down fittings to move the tiedown points outboard. I thought of that because the RV-3B is so small and close to the ground that it's hard to get a decent angle on the tie-down ropes -- they will typically be splayed out at a considerable angle. Thought about it, ran some numbers (my old profession, aerospace stress analyst) and it looked okay but marginal. Finally decided not do do it. One reason was that adding new fittings wouldn't eliminate the existing ones. The new ones would be added weight and the utility of them would be relatively minor. All in all, not a positive change, assuming that I don't get caught out in a 70 mph wind while tied down to widely-spaced anchors on a trip some day.

On the RV-3B, the skins aren't pre-punched, so I needed to locate the hole for the tie-down. I used a scrap of .032 and a 12" long #40 drill bit to back drill it to the spar flange.

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Then I shortened a transfer punch which had a nice snug fit in the threads. It only fit in the threads, not the long hole.

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The small part fit the threaded hole.

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And pushed farther in, ready to go.

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I used a thinner transfer punch to push it. This was the only rod I had handy which fit. It didn't need to be a transfer punch and actually would have been better if it wasn't.

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The combination of the pieces and the tit on the longer transfer punch and the fact that I wasn't backing up the match hole jig meant that the center punch in the jig was relatively small. I used a marker to outline the tie down fitting on the jig so I'd know where to look.

After drilling a pilot hole at the location, I clecoed the match hole jig to the lower side of the leading edge and double checked a couple dimensions to be sure.

PiD6dIw.png


I pilot-drilled the skin, removed the match hole jig and drilled it out to 3/8". The final hole isn't perfectly centered but it's within about 1/32" and that's good enough, especially since I can't move it anyway.

Dave
 
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Plans

Here's what I'm doing for plans.

The plans come in sets. Order a kit and you get the plans for just that kit. When I made my first order, I requested that I get all the plans at once so that I could look around and check things - highly recommended for RV-3B builders. Even with all the plans here, they aren't anything like the double-digit RV plans. These are large sheets of paper, with something just a wee bit better than blueprints on them.

The original plans are over 24 inches tall and long. That was a bit too large for my work tables, so I took them down to Rocky Mountain Blueprint Co. They made me a set that was 18 inches tall. These fit my work benches much better. I've still got the originals for when I need "full size" patterns. It sometimes happens.

They also scanned the plans in and made a single PDF file of them. It's 9.5 mb. On my Mac, they show up quite well. The Mac lives about a dozen feet from the shop so I generally don't need to use the computer to look at the plans.

I also loaded them on my iPad. The iPad (mine is generation 1) is a bit poor at this, though. I know from the Mac that the files have ample detail, but the three apps I've used just don't show it. I've used Goodreader (worthless), iBooks (so-so) and the Kindle app. Kindle is a hair better than iBooks for the plans, and that's still marginal.

If anyone has a better app for viewing these plans, please let me know.

And since my iPad is a 1st generation one, it's very slow loading these things. I mean glacially slow. And old style glacier speed at that, not the new speeded-up glaciers of our climate change era. 15 minutes to load the plans isn't unusual.

Still, if I'm away form the shop and need a look at them, well there they are. And the first page I need is a bit quicker.

Another thing that I did is really useful. I made a parts list in a spreadsheet, that lists the part number, name, what its material is, the as-received source material, quantity, and best of all, every drawing page that refers to it. I printed this out and keep a copy in the shop and another at the hangar, where I store the parts that I haven't used yet, like the fuselage and finish kits. The preview plans are there too.

Since the RV-3B is sort of a unique RV kit, I have a copy of the preview plans for the RV-4 and RV-8 in the shop. When starting something new, those are the places to check, to make sure that the RV-3B design isn't too obsolete. Sometimes it is. In any case, it's a quick and easy sanity check before cutting or drilling something.

Which reminds me that the Mac, just outside the shop, is handy for one important thing. I also check VAF and sometimes vendors for information relating to what I'm doing. You never know. Sometimes the oddest things pop up, like needing to leave the connector cap off the autopilot servo in the right wing. That was the latest useful bit of data I got. Or maybe it was that Lexel is a decent sealant that's compatible with acrylic. One of those. Anyway, thanks, Doug!

And with all these resources at hand, I still sometimes miss things.

Dave
 
I've been working away in spite of nearly continuous interruptions.

The fuel pick-up lines that Van's sells almost fit the RV-3B. I had a pair and found that they were just under 90 degrees as received. I closed them up a bit, not too much, and now they fit fine.

w0Wa0vt.png


It looks like the tool overlaps the hardware on the line but that's just the photo. The line fits fine but there's not a lot of extra clearance.

You might remember that I'm making new tanks. I'm making the various parts that fit the ribs now.

And the slow progress will continue for at least another month.

Dave
 
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2nd Tank Work

Some of the unrelated personal things that took a great deal of time and energy have ended and I can now work a bit more on the plane. But some of them might resume and can't be forecast. I'm working while I can.

The small stuff like the hatches and the rings and the rest of the small parts are all done for these tanks. I've fluted and marked all the ribs, drilled them to the baffle and aligned the frame parts on the wing in the jig.

Here's the right wing.

y7PF437.png


And on the left wing, the skin is on for the initial fitting. Before I got this far, all the tank ribs needed tweaking because they were just a skosh too long to line up with the outboard leading edge. Looking across the leading edge, it now lines up nicely.

hTPHoig.png


Thanks, David Howe, for teaching me about these wooden fittings.

Dave
 
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