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There are several two seat Nieuport 12's out there.
I'm a lucky guy in that my wife has put flying firmly into "my thing" and has put off a ride with me. She's afraid she'd like it too much and says we can't afford two pilots in the family. :P
She did, however, agree to go up with me in the next month or two in order to help me get my Passenger Endorsement. You know, the one every new pilot has to get by taking up a passenger that isn't their CFI. I'm so lucky to have such a supportive, trusting wife to help me flesh out my log book and complete yet another rating.
;)
Found the misplaced construction DVD and was enlightened in the opposite direction of my efforts (yet again).
Bolts are reversed in the compression struts (nut on the outside) and I somehow got the lift tangs inside the wire bracing tangs (I think little elves or pixies or something magically changed them around, as I distinctly remember putting the lift tangs on the spar side).
Oh, well, cable and swags are cheap, and it's an easy fix.
Instead of working on the wings, I decided on an hour and a half of intense psychotherapy:
http://www.darts-page.com/images/tg07.jpg
What's not in the plans is how the lower wings attach to the carrythroughs. In the DVD they show the DVII, which doesn't have a sweep to it and has sleeves in the carrythroughs - which aren't in my set of plans.
So another call to Robert....
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So I discovered that magic ghosts have placed the lift tangs on the wrong sides of the drag/anti-drag wires and took it all apart and put it back together again, and put them in the right places.
I also got a chance to do some basic trig.
The problem with the dihedral with the bottom wings is that it's 2.5 degrees. No way I could ever measure that properly; what I need is how far to lift the end to give it the right angle at the carry through.
So I racked my personal mental wayback machine...one knows the angles and one side of the triangle...where do I remember that from? Oh, it's the "tree casts a shadow X long and the angle of the shadow is Y; how tall is the tree? question.
But in this case I know the distance to the top of the tree only.
Dang...oh! Law of Sines! SineA = Side B/Side C. So SineA x Side C = Side B. Look up the Sine of 2.5 degrees, do the math, and 5.25" is the lift! Just raise the end of the lower wing five and one quarter inch!
I can do that.
Oh, and I'm becoming an expert on swagging cable...
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Math is too hard. I'd just invest in a digital level. ;)
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If one looks closely at the pic where the wing ribs are laid out there is a problem.
The thick things with the holes on the end are the lift tangs for the landing wires, and they're on the wrong side of the drag/anti-drag wires. They should be by the spars and the wires should be on the compression strut side.
Sooo.....tore it all apart and redid it. Got the other wing done, which went much faster than the first, though I did have to reverse the jig when it came to tightening - the lift tangs were in the way of the mirror image, poking down into the table.
Got the carry-throughs put in - what a huge pain in the kiester!
Ideally the holes that go through the verticals and the carry through tube would be level to flight, but with the curved fuselage and the tight spaces I wound up less than ideal. It's all firm and within tolerances, though.
And I got to buy some neat tools for the job.
A drill won't fit in the tight spaces, and a regular drill bit is too short for the long hole; so I went and got a great big long bit of the same size.
The carry-throughs are between the vertical struts of the fuselage and really close to the bottom longeron; one can't fit a drill in there. The solution was to buy a 90 degree drill adapter, which means one can, well, drill at 90 degrees.
The long bit is too long to fit to start, so I got the hole through the first upright tube and the first wall of the carry-through tube.
But the long bit was still too long.
Sigh.
Gotta cut the long bit down by about five inches. Now I don't know what the "right" way to do that is, but here was my technique:
1. Take a hack saw and run a groove around where I wanted the cut to be on the shaft of the bit.
2. Put the bit into a drill.
3. Put the hacksaw blade into the starter groove.
4. Turn the bit at low RPM's and work the blade back and forth a bit to keep it from getting too hot.
5. When the center of the bit got really small through the cut I snapped it apart.
And now it was short enough to fit between the uprights but long enough to drill all the way through.
Leveled the fuselage, measured down for where the carry-throughs go, and level them; it's a never mind about anything but getting the lower wings level with the upper wing and evenly spaced between them, after all.
Clamp and drill. I'd like to say my bolts go through all level and dead on center, but they don't! There just wasn't enough clearance to get that bit down low enough; so I've got between seven and two degrees off depending on which hole one is looking at!
I also need to get some bolts for them - I've somehow lost them! To continue on with the build while I wait for them to arrive, I grabbed some off the shelf bolts of the same size to provide stand ins.
Next up is to start building the wing jigs for mounting the upper wings and to install the "blades" that go into the lower wing carry-throughs so I can mount them to the fuselage.
Now things get interesting! With the carry throughs in I can set the upper wing compression struts and build their frames; when I mount the lower wings the carry-through distances get locked in. With them locked in I can put in the elevator and aileron controls. With the controls in I can put in the seat. With the seat in I can lock down the location of the rudder pedals.
And of course with the compression struts locked in on the upper wings, I can start putting ribs on all four wings....
I'll put some pics up later....
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Here's some pics of the stuff I've done the last couple days:
Stacked the lower wing spar assemblies to double check that they are mirrors of each other:
http://www.darts-page.com/images/Nieuport/lw017.JPG
I didn't take the usual "step by step" pics of the carry-throughs, as it was cold and I kept moving to stay warm!
But it's pretty straight forward. The fuselage is leveled both ways (tail raised to flight position) and the tubes then placed on the level using little blocks and some clamps once it's measured down from the top longeron.
http://www.darts-page.com/images/Nieuport/ct01.JPG
Because the most important thing is that the wings are level and consistent with each other, any inconsistency in the fuselage against the level is disregarded. It's irritating - the eigth of an inch twist in the whole of the 12 foot long fuselage is in the first 28 inches.
Anyhow, once the measurements and the level is established, the fun began! It's pretty tight to get at the holes that have to be drilled, and took on a multiple step process.
First a standard length drill bit was put into the 90 degree adapter and with care to keep it on line with the longeron and level to flight the hole through the first upright fuselage tube and into the first wall of the carry-through tube, which is as far as it could reach.
Next the long bit (which was too long to begin with and had to be cut down) was placed into the holes and slid forward to the opposite wall of the carry through tube. This gave enough room to put the 90 degree adapter in and finish the hole.
I slugged in a bog standard bolt since I have misplaced the proper AN ones....sigh. Well, let's all stimulate the economy through ignorance!
http://www.darts-page.com/images/Nieuport/ct02.JPG
One thing that I have been grousing about is the "blades" used to hold the lower wings into the carry throughs. The lower wings aren't actually fastened to the fuselage this way - the landing wires hold them tight to the fuselage - but rather just work as guides to keep them in place. The method is to put an oblong plate "blade" of aluminum in the carry through and then slide the wings onto them.
It's not detailed in the plans and I just plain dislike that solution. The rear spar of the wing is smaller than the carry through tube and the blade is as well. They just don't extend into the wing far enough for my comfort.
My trial solution is to shape some wood that fits both smoothly with the right rearward sweep and dihederal angle.
http://www.darts-page.com/images/Nieuport/ct03.JPG
I have a piece of tube that Robert gave me for the rib jig that I used to check for fit on the larger spar to see how it fits.
http://www.darts-page.com/images/Nieuport/ct04.JPG
Pretty cool in that it is the same length as the distance from the start of the wing to the compression strut bolt.
http://www.darts-page.com/images/Nieuport/ct05.JPG
I'll double check the dihedral angle - it looks too steep to me.
http://www.darts-page.com/images/Nieuport/ct06.JPG
I worked up the rough blank for the rear spar as the light began to fail for me...
http://www.darts-page.com/images/Nieuport/ct07.JPG
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Since it's a deviation from the plans and a bit Southern in solution to use wooden plugs to guide and fix the lower wings to the fuselage, I called Robert Baslee to ask about it.
He said it's a very acceptable solution and added that I need to paint or otherwise treat the wood to prevent any reactions to the aluminum and to prevent rotting.
I fit the left wing onto the aircraft, and to my pleasant suprise found it not only fit well, but that I had nailed the sweep and dihedral dead on!
We also had a discussion on my plans for the upper wings.
Because the inner compression strut must align with the fuselage and the outer one must align with the lower wing (including dihedral) for the interplane struts, my plan is to make a rig that suspends them before assembly. I'll ensure they're center, leveled, and appropriately distanced and with the lower wings in place drop a plum bob to mark the compression strut locations for the upper wings.
Then I'll take the whole mess down and build the upper wing frames based on my marks.
Robert said it's a slight case of over-build, but I put it in the "must be right" category - the box kite must be a box! And I want all the stresses to be transferred equally and through the right points in the right way.
He naturally agreed that whenever possible "closer enough" should be "dead on" if one can make it that way.
Now I need two days of clear weather, as with wings the plane won't fit into my little work space and has to be done in the open of the back yard.
I'll put a pic up tomorrow....
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I've been lazy in updating this thread....
Both lower wing spars are done, along with the plugs for the carry-throughs. Naturally the weather has been yucky and I've been up for some overtime over the hollidays, so work slowed considerably. It's bugging me to have an airplane in the back yard not getting built, and I guess it shows as the wife commanded me to get out there and do something on it.
One of my big concerns has been getting the upper wing outer compression strut to align directly over the lower wing's outer compression strut, as the interwing struts attach there - and I want them to be vertical! I don't mind doing math, but nothing beats physical measurements.
I didn't need to make a whole cradle for the upper and lower wing spars; I only need to measure the rear spar on one of the wings. So here's the Alabama rig:
The camera might not be level, but the fuselage is! Note that the left rear wing spar is in the rear cabane, but not levelled.
http://www.darts-page.com/images/Nieuport/wg_001.jpg
Now that wing spar is level!
http://www.darts-page.com/images/Nieuport/wg_003.jpg
Lots going on with this picture - note the fantastic board in the foreground. It's stuck into the ground and tied to the chair for reinforcement. The spar is held in place with a bit of reject drag/anti-drag wire looped through two holes and tied in the back.
http://www.darts-page.com/images/Nieuport/wg_002.jpg
The board past that is stood up on the lower wing compression strut to see where it will hit the upper spar.
http://www.darts-page.com/images/Nieuport/wg_004.jpg
Too easy to ensure it's vertical with a level and make some marks with a Sharpie.
http://www.darts-page.com/images/Nieuport/wg_005.jpg
Naturally it's rained and been yucky the last couple of days, so things slowed down on the build. I'm getting antsy about the delay again.
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Good update Frank! To have a WWI replica fighter going together in your backyard...how cool!
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With the weather switching between freezing cold and tornado near misses, I hadn't gotten much done lately.
But it's improved dramatically, so the upper wings were drawn out and the spars for the right wing getting laid out. Pics tomorrow...
