John's
Plane Week 5
Flying Wires, Cable Routing, and Engine Systems
August
3, Monday
I report for work at 1 PM. A steady stream of walk-in customers
and phone orders delays building the plane. Tony and Ed from
Bicknell and Monroe City are collecting parts to repair Ed's
plane after his engine-out dropped him into his own cornfield.
He was not hurt and he claimed he caused more damage to his
corn getting the plane to the road than to his airplane.
This leads to a discussion of the best way to set down in tall
corn. Everyone agreed flaring out at the level of the corn
tassels would give you the best of a bad situation. Ed said
he did that and the plane stalled and stopped moving forward
at the same time. This maneuver may flip the plane on its back
as the corn absorbs and cushions the shock. Ed unbuckled and
began his retrieval effort quickly.
Next, Gene and a friend show up and about six of us head for
the field and Mark gives the friend an introductory lesson
and another ex-GA pilot gets hooked on ultralight flying.
After supper about 8:30 Mark begins teaching me how to make
wing wires.
First, I assemble the tangs and thimbles and nicos and lay
a set out in the order I will use them. Mark turns to his files
on the plane I am building and pulls out Wing Wires. This includes
hard earned information on the exact amount of rubber to strip
from the cables, in what order to assemble the cables and the
exact length to cut the cable so the assembled wire will be
precisely the right length, both left and right side.
First I unroll enough cable from the spool and strip several
inches of rubber from the end. I insert the cable through 2
nicos and then through the back of a thimbled tang. Next I
curve the cable back through the two nicos.
Prepare to crimp the nicos like this: grip the first nico in
the crimper to free both hands, keeping a bit of pressure on
the crimper handle with your shoulder. Center the nico in the
crimper jaws, push the doubled cable through the first nico
until you see both bared surfaces. Place your left thumbnail
on the edge of the rubber on the cable and slide the end of
the cable against your thumb nail. This insures the end of
the cable is even with the edge of the rubber covered cable.
This is extremely important because the size of your bend will
determine the total length of the completed wire. Now, slide
this doubled-over cable into the nico until your thumbnail
acts as a stop against the nico. Check that the nico is in
the center of the crimper jaw and push your shoulder into the
crimper handle until the nico is crimped. This requires a solid
push and repeated performances will make your shoulder sore.
Now move to the second nico. Grip it in the crimper jaws. Slide
the cable through the nico until it pulls the thimble tight
against the nico. Make sure the assembly is squared away, i.e.
the wires are parallel, the thimble is tight and in a straight
line out from the cable and crimp the second nico. I finish
crimping this end by making a second and third crimp on each
side of the center crimp of both nicos. The ridges and flats
on the nico should be balance and even. The nico should not
have a distorted look, although you have been distorting the
hell out of it.
Next, I hook the tang over a pin and stretch the cable from
the spool out to the exact length required by running a steel
tape measure along side it. I cut the cable and assemble the
other end of the flying wire by repeating the steps above,
taking care to install the proper fitting on this end. Wires
could have a tang and a thimble, two tangs, or a five hole
tang and a single hole tang on opposite ends. In paying attention
to the details of crimping you could easily lose your place
and attach the wrong piece and have to start over. That's why
Mark suggested for each cable I lay out the pieces in the order
of assembly. By 10:30 I have made 3 of the four wires we complete
that night and so off to bed.
August 4, Tuesday
I
continue working on the upper and lower flying wires. I complete
2 sets of the upper wires, These are fitted first into the
five hole tang that will fit over the king post, so I will
make a left and a right for each set. The other end of the
four upper wires will each receive a tang. This cable is
stainless steel and coated with rubber. It is of aircraft
quality and very expensive. I am again anxious not to screw
up. Mark insures I get the first cable in place, the trailing
edge inboard wire, on both left and right side, That way
I can't go wrong if I think my way through step by step.
Besides, Marks file on how to do this is right beside me.
I place a rule on the file of each wire I work on. I read
the cut length at least three times before I cut any cable.
Mark then goes to work filling orders for his mail order
business in the same room so I can check with him if I have
questions. I work slowly and carefully, carefully.
The ideal nico installation will have 3 crimps, evenly spaced
with narrow ridges at the ends of each flat and in between
each crimp. The cable end should not protrude from the first
nico, nor will it recede too far inside. Once the first nico
has its first crimp, the assembly is held in place and crimp
the second nico is easier. Still, you must concentrate on squaring
up the tang or thimble and having the doubled cable lengths
parallel to each other so when completed and installed, the
wire will pull evenly on both sides of the fitting. Here is
a picture of the ends of a set of wires I made.
I screw up three times making the set and must cut out
my nico and start over. Luckily, the long cable can be
used to make a shorter one so only a short piece is wasted.
Finally, after copiously sweating from anxiety more than
the heat, I finish the 2 sets of upper wires, 2 lefts and
2 rights. Mark inspects them and finds them all within
tolerances but one. I have somehow cut one inboard wire
1/4" shorter than its true measure. I
must cut it from the 5 hole tang and install a new wire.
Since the inboard is a short one, I have also created a
beautiful piece of scrap. Deep breath.
This project, building the plane, continually throws me into
new situations. About the time I am relaxing with a task, Mark
assigns me a new job and I go through the anxiety of new man
on the job. At last, however, I have two complete sets of flying
wires. Here they are:
August 5, Wednesday
Today is my grandson Jared's 12th birthday, I recall upon waking.
building this plane is high priority with me. Normally, I would
be celebrating his birthday with him and his family. Well,
I sent him a card and a present.
To the DQ for breakfast about 7 am where I find Mark with a
student of his, Tom. We all head for the strip for some flying
and a second student, Gene, shows up. Flying and hangar flying
until lunch and into town for pork chops at Lucky Linda's.
Two customers show up at Linda's and we spend much of the afternoon
with them, Dan and Charlie from Central Kentucky. Dan buys
supplies for his business and Charlie needs several items so
we head out to the strip and the warehouse and send them on
their way. Back at home, a friend drops in and visits with
Mark until about 8 that evening.
I use the time to repair an aileron I bent on my Sprint back
in Brazil last Saturday. Since I have already made a set under
Mark's supervision, I can do this by myself. Mark, I feel has
given me this power and I feel good. I know which tools I need,
where Mark keeps them, how to drill precisely the 3/16 holes
in a row through both sides of the replacement leading edge,
using the mills centering V-blocks and a level inserted into
the first hole I drill. I drill the 1/2 inch holes in the trailing
edge for the aileron compression struts, drill the eye bolt
holes and rivet the blind nuts in place. I complete the repair
and spend some time visiting with Mark and his friend, who
is also a flyer. At 8:45 Mark is on the phone with a customer
and I head for home.
August 6, Thursday
This morning I made 2 sets of drag wires, 4 total. Mark laid
out the parts and I did the work, feeling comfortable, cutting
and crimping, fairly precise work. All other wires we will
make on the airplane.
I mount the throttle bar under the seat support and Mark
cuts two 7 inch steel throttle levers on his plasma cutter,
just a 1/2 inch longer than the standard QS aluminum levers.
We expect this to give us a slightly smoother action and
greater strength. Mark then devised a handle of 2 aluminum
knobs, 1 inch in diameter, turned and polished on the lathe.
He drills the center and countersinks it to the depth of
the nut and the bolt head. We tamp the nut and bolt head
into the countersink and we have two knobs that will screw
into each other through the top end of the throttle lever.
A neat job that fits my hand nicely. Mark hands me the
set he made and says, "Here,
go make the other set." Again, I feel comfortable on the
metal lathe, a machine I had not used before Mark put me
to work on it last week. This time I need no instructions.
I complete the set and install it on the other side of
the trike. To my eye, the sets are indistinguishable. Here
is a picture of one set installed. Beautiful or not?
Mark has already installed the carbs and today he makes and
installs the cable splitter and the throttle cable. This requires
and expertise I do not have and I mainly watch and hand tools.
Marks explains as he is installing the splitter and when it
is adjusted correctly, he removes it, hands me the parts and
tells me to reinstall. On the job testing. I have been paying
attention and I get it right. this project is removing the
mystery of how this machine works. I feel confident when I
do have problems of maintenance I will be able to at least
diagnose the problem and probably repair most of the systems
I have worked on so far. Here you can see the splitter in place.
You can also see the replacement hose Mark has installed in
the 582's lubricating system. He believes the original hose
not a durable quality, so routinely replaces them even on new
engines.
Since you wouldn't want the throttle cable to be the mechanical
limiting device of the throttle motion, you must devise a stop
system that prevents the linkage from receiving this stress.
Mark bolts two small metal stop tabs on the cross bar. These
tabs contact the tri bar immediately after the throttle is
fully released or fully open and before any mechanical stress
is applied to the throttle cable.
Out to the strip to collect parts: a muffler and connections,
an electric starter for my 582. I need help to start Mark's
582 and so I need the electric starter on my plane, despite
the disadvantage of the extra weight. We locate the starter
on the front of the engine and rotate it for best fit. This
turns out to be at the 12 o' clock position and we must grind
a hole in the housing of the 582 to accept the starter gear.
Mark uses his pneumatic grinder while I assist by spraying
WD40 on the grinding blade. He must grind a semi circle almost
2 inches wide by an 1 1/2 inches deep and though Mark is a
big man he rests every few minutes before this job is done.
We set the starter aside for mounting later.
We close out the day with the muffler. Mark welds the mounts
on the muffler after installing it temporarily to mark the
positions. I clean and paint the muffler, the elbow and the
exhaust manifold and hang them up to dry. Here they are:
August 7, Friday
Today we work with almost no interruptions. I install the brake
cables and the brake handle. In these two pictures you can
see the brakes with springs and cable installed and the handle
in place.
I route the brake cable along the axle with standoffs made
by inserting a tie-wrap through a short piece of tubing. This
protects the brake system form vibrations and looks pretty
nifty, too. Here is a picture of the routing of the brake cable.
While I am doing the brakes, Mark is completing the throttle
linkage. He routes the cable as he instructed me in routing
the brake cable.. He must solder a cable tip to the cable after
determining exactly how long the cable must be. I check the
carb piston positions as he locates the wide open throttle
position. Once in place, we check for full closure by listening
for the telltale click as the carb pistons bottom out on the
carb housing.
Mark points out a pilot should make this check before starting
the engine. The linkage is secure and safe but don't assume
this. If somehow the linkage is bollixed up, the throttle would
be opened an unknown amount, even though the throttle lever
is against the back stop. Seat belts fall down around this
cable and might pull the cable out so it rests on the edge
of its tube rather than inside where it belongs. This could
pull open the throttle linkage almost a 1/2 inch. Ever been
run over by an airplane? You won't be the first. The linkage
is in place and I take another picture: Note the neatly installed
cable routing with standoffs.
The brake handle isn't quite finished. I cut the handle and
bend it. I install it to check position next to throttle handle.
It's too close. I cut off another inch and install again. The
handle nestles too closely to the axle strut for easy grasping
and Mark suggests a second bend outwards. That is the finishing
touch. I can now grab the brake handle by feel and do it easily
and positively.
Late Friday afternoon we start to install the muffler. Should
be quick and I head for home. As we attempt to install it we
discover one of the brackets has an off center hole and must
be removed and rewelded. I grind the weld off and Mark welds
the bracket on in its proper orientation. We install the muffler
and elbow and Mark welds the spring hooks in place. I assist
by holding them in place with a vice grips. We remove the muffler,
I clean it up and repaint, and finally we install it for the
last time. I think. I hope. Here it is looking good.
The fifth week of the project ends about 7 pm and I head
for Terre Haute.
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