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Spars
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Here is a view of
the stacked spar webs. 3/9/99 |
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This is how I made
sure the spar caps were kept at a consistent spacing. 3/9/99 |
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Here are the various
spar fittings. 3/9/99 |
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Here are the fittings
being attached to the spar. Note the sliding drawer that I built to hold
the plans. The drawer is attached with 24" full extension drawer slides.
It keeps the plans safe and out of the way. 3/9/99 |
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Here is the spar
web after being dimpled and countersunk. 3/9/99 |
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Here are the spar
caps after being drilled and countersunk. 3/9/99 |
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The last step in
building the spars is to lap the inboard portions of the spars over each
other so the 5 alignment holes match up to each other. You then bolt the
spars together so the holes stay aligned and then drill the holes up to
1/4". 5/7/99 |
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The center 3 holes
are easy to drill out because you only have to drill through the thickness
of the spar webs, less than 1/2". However, the outer two holes are the
holes that will eventually hold the pins that hold the wings onto the fuselage.
These holes not only go through the webs but also through a couple of 11/8"
blocks plus the 3/16" angle supports. So you end up having to drill through
about 3 1/2". 5/7/99 |
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I did not think this would be a problem
because I had built carefully and the holes were lined up pretty well and
I assumed the drill would tend to follow the hole naturally. WRONG. 5/7/99 |
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I first drilled the hole 64th larger and
everything looked good. I then drilled another 64th larger and the drill
wandered and the opposite side of the hole became an oval. No
problem, I though, I will just drill the next size up from the oval side
and every thing will even itself out. WRONG. I keep doing this until I
was past 1/4" and I was getting worried 5/7/99 |
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I then bit the bullet
and took apart everything, removing the blocks and the supports to see
what went wrong. The holes through the center webs looked OK. But I could
clearly see the off center holes in the outer blocks 5/7/99 |
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I cut new blocks
but only drilled the pin hole in two of the blocks. 5/7/99 |
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I reinstalled all
of the blocks and bolted the spars together again. I then clamped the whole
thing onto my drill press. I then used the drilled blocks as the guide
to drill the undrilled block. This worked well and I then had nice holes
that lined up with each other. I then wanted to bring the left and right
holes to the same size. The hole through the right blocks was a little
smaller because I had stopped drilling when things first went wrong. So
I clamped the spars in my drill press again and started to enlarge the
hole. The first 64th went well but the second wandered and ovaled the hole
again. 5/7/99 |
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I talked with Jeremy
about this problem. He said they had this same problem on one of the prototypes
that they are building. Other builders have told me that they did not have
a problem at all. The holes will eventually be enlarged to 3/8" when
the wing box is constructed. My holes are at 5/16" now so I still have
a little room to work with. My idea is to grind a slight taper into the
first inch or so of my drill bits so that they will follow the holes better
and not wander off center. Jeremy thought that there were special step
drills made for just this problem. He was going to check into them but
thought that they would expensive. However, with the amount of money and
time I have sunk into my wings, I would rather spend a couple of hundred
bucks to get a set of bits that would keep me from ruining my wings. I
could always sell them to the next builder. 5/7/99 |
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Here are the various
fittings for the rear spar. 5/7/99 |
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Here is the splice
plate that holds the two sections of the rear spar together. If you have
a 10' brake and can bend your own spar so you wont need this plate. However,
if you buy the formed channel kit, it comes with a couple of 8" rear spar
sections and a couple of extra feet of spar channel to make the spar tips
from. 5/7/99 |
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Here are the reinforcements
for where the aileron push rods go through the rear spar. . 5/7/99 |
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Here is a view of
the spar root attach plates. You can see the hole where the flap push rod
goes through the rear spar . You can also see the root rib attach
angle. You may notice that the plates for the left and right rear spars
are on opposite sides of the rear spar channel. 5/7/99 |
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Here is the tip
spar web. 5/20/99 |
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Here are the web
spacers. I found the best way to hole them in place was to tape them in
place with double sided tape. 5/20/99 |
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Here is the pitot
and static tubes. I had purchased a set from Aircraft Spruce but they looked
crude so I used some of the parts to make my own. 5/20/99 |
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 CAUTION:
This web site is in no way a publication of Sonex, Ltd. or any other corporation.
All products mentioned are not necessarily recommended for use, but are
included for informational purposes only. Builders tips and instructions
are not meant to replace the plans and instructions from Sonex, Ltd.. All
Builder's tips and instructions are presented only as a source of information
and a forum for exchange and the sharing of ideas and construction methods.
NO responsibility or liability is assumed, expressed, or implied as to
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the suggestions, ideas, instructions or examples on these pages, does so
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© 1999-2000 David Koelzer.
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