RELATED PROJECTS / DESIGN IDEAS
Up until now, I have had little exposure
to tools, less to fiberglass work, and no exposure whatsoever to aircraft
building,
except radio controlled
models. With regard to engines, I used
to change oil, filter and spark plugs to my first few cars while
in college. In addition, I do not like researching on
the internet what others have done. I
tried it at the beginning and I believe
it is much faster and easier to discuss issues
directly with the kit’s manufacturer or with some of my close builder
friends.
This proves that you do
not have to be experienced in any of the above to build the airplane’s
fiberglass structure.
With respect to the
electrical and engine installation, I will give you my impressions when I get
there.
I am sure that others have
come up with similar, or even the same methods and ideas listed below. I apologize if I do not know
and give them proper credit. I list below what I have come up with for my
own records and for the benefit of others that, unlike me,
seem to like internet research
or do not have the blessing of available experienced builders. I give proper source credit in the text
below whenever I am given
and use, what I believe to be, ingenious and uncommon ideas from others.
LINKS TO
PHOTOS AND EXPLANATIONS BELOW:
1. EPOXY HOT BOX (Section
Photo Album)
Instead of building a wooden box, I decided to buy an
unassembled plastic cabinet and adapt it to keep the epoxy hot during the
winter season. I had scrap wood around that I could have used but I did not
want to spend the time building and I wanted the box to be light so I could
move it easily between the garage and the laundry room (heated area) while not
in use. Although I was limited to the sizes available, I found one that gave me
plenty of space to place the epoxy pump; a Black and Decker Space Right Wall
Cabinet (Lowe’s). I installed a slide switch
dimmer in a plastic box on the top left back corner, making a hole to access
the dimmer switch. I found a large plastic cap to use as a base for a ceramic
socket and installed it on the left side of the cabinet. I made the proper
connections between the dimmer and the bulb socket and finished them with the
use of a recycled appliance cord. I insulated the inside of the cabinet with
garage door insulation and double-sided tape. A 75w incandescent light bulb took
care of the heating. I placed a $7.00
digital thermometer on top of the cabinet with the outside sensor inside
the box. As much as possible, I sealed any joints through which heat could
escape with clear and /or electrical tape. I placed the sensor away from the
bulb and moved it around until I was satisfied with the average inside
temperature reading.
2. MOBILE WING RACK (Section Photo
Album)
I never thought that this
piece built with wood recycled from the kit’s crate would turn out so
useful. By lifting the outboard end of
the wings for access, I easily match-sanded and installed the ailerons and
rudders from a standing position, without ever removing the wings from it. Almost all work on the canard ends and tips
was done with the canard on the rack. In
addition, I move the whole assembly around in my garage without help, and very
little effort, once the casters align with the direction I am pushing. When put away, the fuselage fits between the
winglets and the work benches. The wings
and the fuselage (without strakes) would occupy less than one car space in my
garage allowing me to fit the kit and my two cars in the garage when not
working. This lasted only until I started
building the strakes, of course.
Same as above, these dollies allow me to move the
fuselage around without effort. Although
it has become heavier as building advances, I still can take the gear legs off
the dollies by myself, when necessary. I
used 2x4s and 3 inch caster wheels.
4. METHOD
TO STABILIZE INCIDENCE GAUGES (1)
(2) (3) (4)
I glued or taped some foam pieces to the wing and
canard incidence gauges supplied with the kit to make them stable while in use
during construction.
5. EPOXY
/ JEFFCO MIXING TOOL
(Photo)
I bent a clothes hanger wire and placed it on my
adjustable speed drill to help mix the epoxy or Jeffco. I formed the base as wide as the bottom of
the mixing cup to avoid unmixed epoxy components at the bottom corners. It
helps mix any epoxy resin fast, thoroughly and effortlessly and works perfectly
when mixing in cabosil, flox, milled fiber or microballoons. It turned out to be a very effective mixing
tool.
6. METHOD TO POUR LIQUIDS FROM ONE QUART CANS WITHOUT WASTE (Photo)
Open holes at the bottom of 9oz plastic mixing cups and secure them to the top of the cans with strips of duct tape. Let the setup sit for a while after pouring and the resin or paint will return from the cups to the can.
7. METHOD TO ADJUST/ALIGN BOTTOM STRAKE LEADING EDGE AND WING (Photo)
I noticed the left bottom strake leading edge ended up about 1/8” aft of its position so I devised a set up with some sprinkler PVC pipe to correct it. I applied pressure and heat to bring the leading edge forward and minimize filling and sanding later.
8. METHOD TO MAKE FUEL STRAKES BULKHEAD/BAFFLES (1)
(2)
(3) (4) (5) (6) (7) (8) (9) (10)
I did not like the method recommended by the manual
and used this one to cut the strakes’ baffles and bulkheads. After installing the bottom shell permanently
and fitting the top shell, I drew the exact position of all bulkheads and
baffles on both inside surfaces of the shells (1). Using the same method of transferring the
contour of the fuselage to the strake shells, I transferred the contour of each
shell to an oversized piece of thick cardboard for each baffle/bulkhead.
I trimmed/fitted the cardboard pieces to the inner surface of the shells. This
was easy to do since the inside of both shells could be easily accessed and all
shaping and fitting was done comfortably. Note that each cardboard piece
was about 3/4 the total height of the part, allowing the cardboard pieces to
overlap (2).
I hot-glued pieces of tongue depressors as a base to the bottom templates
and taped them to the bottom shell to keep them in place (3).
I cut a hole on both matching pieces to use for internal clamping in
place. Initially, I estimated the height of each part based on factory
paper templates (4).
I temporarily fixed the top shell with clecos. By looking at
the setup from the inside, I was able to determine the necessary adjustments
for correct shape of each part. Actually, placing the top shell on top of
a slightly high set would normally push the top portion to the right
height. In any case, by loosening the clamps I could easily move the top
of each template (up or down) to touch and exactly match the height and contour
of the top shell (5).
I then fixed the templates with some wood screws. These now became my
definitive templates. I transferred them “very” carefully to the sheet of
glassed foam, to minimize sanding. I cut them about 1/8 oversize with the
air saw and used a 36 grit sanding disc on the air grinder to get to the cut
line and finished with some rough sanding. Most sanding adjustments were
done to fit the part to the bottom shell. I hot-glued the trimmed parts
to the bottom shell (6)
for final shaping with the top shell on and I had to hardly sand anywhere. I
worked my way inboard to not block vision to any of the parts. Once you
trim the bottom, the top matches rather accurately the first time. The
absence of tongue depressors on the definitive part lowers the bulkhead/baffles
a bit and adds to the small gap that you will need on top for the strake top (7).
COMMENTS:
I went longer than the actual cardboard templates to allow adjustment due to the
thickness of the glassed foam (thicker than the cardboard) and for the
necessary sanding to match the angles between the parts; especially the acute
angle of the parts that meet the strakes’ leading edges. Pay close attention to the leading edge contour
area where the foam starts. It is kind of tricky because it has the same
acute angle, as the leading edge, across the part. It takes some time to
make the templates accurate but you work comfortably (much better than in and
out the fuselage). Support the inboard of the top shell. Its own
weight will lower it and this will give you an incorrect and changing
reference. I hot-glued small pieces of 2”x2” to the fuselage for the top
not to move (8). The parts came out really clean (9 and 10) using this method. I expect to use the
same templates for the other side, significantly decreasing building time on the
second strake by not having to make a second set of templates.
9. METHOD TO DETERMINE GAP
BETWEEN STRAKE BULKHEADS AND TOP SHELL
(1) (2)
I placed small beads of modeling clay on top of the
cap strips and leading edge and fixed the top with clecos. This gave me a rough idea of the gap and the
amount of Jeffco needed to install it. I
know that the modeling clay is harder than the Jeffco mix and that the actual
gap should be narrower than shown.
However, it gives you a good idea of how the top sits. I removed all clay residue, cleaned
thoroughly with denatured alcohol, sanded the areas and cleaned thoroughly
again with alcohol to remove all clay residue.
10. METHOD TO
OPEN
PRECISE HOLES ON FIBERGLASS (Photo)
I
used circular saws to open the wing bolt access holes on the bottom strakes and
found them hard to control for fine accuracy.
Unlike wood, the foam density is not enough to grip and guide the drill
bit, yet the fiberglass skins grab onto the saw and make it vibrate and move
around. Maybe others have used them
successfully but I will never use them again on fiberglassed foam. Now I use the following method to open all
holes bigger than a ½” drill bits accurately.
I draw the exact circle with a fine point marker on a compass. I use a grinding bit on a Dremel to remove
the inside material and change it to a sanding drum to get closer to the
edge. I then finish the edge by hand
with rounded files, sanding discs and sanding paper as needed. I found this method to be simple, fast and
very accurate. I follow the same method
when I want to cut rounded parts. The
picture of the gas cap (link above) is an example of a hole I made with this
method.
11. METHOD
TO CLOSE THE STRAKE WITHOUT FURTHER REINFORCEMENT WORK (1)
(2) (3) (4) (5) (6)
The manual instructs to close the strake, complete the
main spar-top strake reinforcements from the sides and install the rear
bulkheads as a final step. During
construction of my first strake, although I knew that neither approach would be
easy, I thought that it should be less difficult to install the bulkheads
before closing the strake and reinforce the main spar-top strake from the sides
later, with the fuselage inverted.
However, ideally, one should be able to close the strake without having to
work further behind the fuel tanks. So,
for my second strake, I started thinking about ways to accomplish this and came
up with the following process, which I ran by S. Swing at the factory. 1) I installed the rear bulkheads with their
corresponding top flanges as I did with the other bulkheads; 2) I formed a couple of foam pieces that
adapted to the inside top of the main spar, as much as possible, and two other
to fit between the rear bulkheads and fuselage, at the same level of the
corresponding flanges, placed some ½ inch upholstery foam on top and covered
them with duct tape; 3) I applied a mix
of EZ-Poxy and cabosil to the inside of the spar to even out its surface for
better surface contact of the layups; 4) I pre-soaked two-ply BID on plastic and
lay it on top of both foam pieces; 5) I
positioned the assembly in place with one half of the layup pushed against the
inside of the main spar and the other sitting on top of the foam piece between
the bulkheads; 6) I removed the excess cabosil mix and finally placed peel ply
over the assembly; 7) I used clecos to keep the duct-taped top strake in place
for curing. This method produced flanges
that were filled with microglass and structural epoxy, as needed, during final
installation, allowing installation of the top strake in one step. Picture 6 above shows an upside down view of
the flanges, from the outboard access hole, after final installation. Unfortunately, I did not take the time to
think about this process before closing the first strake. I know reinforcing the outboard portion of
the closed strake should not be a big problem but working from the cabin on the
inboard section will not be as fun.
12. METHOD FOR REMOVING POP
HEAD RIVETS
My approach may be somewhat unorthodox but it has proven
to be fast, simple and secure every time. When I want to remove a rivet, I
use a drill bit of the same rivet size in a slow drill and very carefully drill
the rivet head until it separates from the body. The hole in the rivet head
acts as a guide for the drill bit.
Sometimes I just stop slightly short of separating the head and
just brake it off with a slight pull. If done slowly and carefully,
it allows easy removal of the rivet parts leaving the hole intact for the new
rivet.
UPDATE: I just
saw this method explained in a new building video at the EAA website.
13. METHOD FOR ACTIVATING
AND ADJUSTING ACTUATORS DURING CONSTRUCTION
Instead of a 12v battery, I use a 12v AC adaptor with alligator clips to activate both the elevator trim and speed brake actuators during construction.
14. BALL BEARING
INSTALLATION
(Section
Photo Album)
I
noticed that the screws holding the aileron bearings in place would not sit
flat against the flange. This actually
deformed the ball bearing case when tightened in place in the rear aileron
bracket, causing an abnormal friction when rotating the bearing and giving the
impression that it was damaged. By
removing the bearing, the deformity was eliminated and the bearing was back to
proper functioning. To resolve the
problem, I Dremel-grinded AN960-416 washers to fit in place and level the screw
heads against the bearing flanges. Make
sure the washer allows proper tightening of the flange against the bracket so
the bearing does not become lose. I did
not have to, but you may have to slightly sand a face of the washer for
this. I used the same setup with the
bearings of the aileron torque tubes and all rotate smoothly now.
15. ROLLING OVER THE
FUSELAGE (Section Photo
Album)
This is a known way of doing this. However, I felt like documenting as it took a
lot of planning and preparation to do it in such a steep driveway. Having to bring several of my friends and
relatives to help, I wanted it to be a quick and effective process. I used the semicircles that John and Craig
had passed on to me. I bolted them to
the main spar with only one bolt to allow rotation for clearance through the
garage door height. With the help of my
brothers Ed and Javier, and fellow builders Russ, John, Craig and his brother
in law Mick, we rolled the fuselage down the driveway mounted on my fuselage
dollies. We removed the dollies,
straightened the semicircles and inserted the second bolt. Some of us lifted the nose up toward the
driveway and others received it on the opposite side as Craig was slowing down
the drop from the street with a rope tied up to the gear and looped around the
bumper of his car. Once upside down, I
supported the canard bulkhead on a rolling table, bolted the fuselage dollies
to the semicircles and rolled it up the driveway back to the garage. I removed the fuselage dollies and left the
fuselage supported by the semicircles and a sawhorse under the canard
bulkhead. Finally, my brother Javier
announced the arrival of the snacks to those involved, brought by my then
relaxed wife Ygebor.
Several months later, once done with all the building
steps I could think of that would be better done while the fuselage was upside
down, we reversed the process to roll it over back on its gear. Friends John Schoorl,
Craig Woolston, Juan Carrillo and Glen Kadohr came to help me with the
task. We attached the dollies to the semicircles; lowered the nose slightly
to clear the garage’s doorframe and started rolling it down the driveway. We rotated the nose 180° and took it all the way to the street. We removed the dollies and started rolling it
over supported by the semicircles. Once
over the top, we all started moving to the receiving side while Craig continued
to control the rotation with ropes tied to the nose gear strut. We placed a dolly under each gear and then
pushed it up the driveway. This time the
fuselage cleared the garage doorframe without a problem. It only took us about 20 minutes to do it
this time.
Although he does not appear in the pictures, my 9-year
old son Alan helped too. As
usual, I designated him as official photographer for the events due to the
quality of his pictures.
16. METHODS FOR WORKING WITH
ACRYLIC (Plexiglas®)
Cutting -
I use a Sharpie marker to draw the
shape of the part, which is easily removed with denatured alcohol. I score the sheet with a utility knife and a
ruler and then bend it against an edge as if it were glass to roughly cut the
piece oversize. I then use a 36 sanding
disc on the 90° grinder for fine shaping. Applying the disc slowly against the edge of
the part melts the plastic. Although it
normally remains attached, it brakes of cleanly and easily by hand or by
sanding it off from the other side. I
finish the edges with fine sandpaper (180 - 320 grit).
Forming -
I use a method initially recommended
to me by
Drilling -
I do not find it necessary to use
special drills for acrylic; at least not for the thickness of the parts that we
normally use (3/32” to 1/8”). The key is
not to rush the drilling by applying pressure, as you would normally do in a
wood or metal part; and to use increasingly bigger bits to get to the necessary
size hole. I usually mark the drill
guide point by rotating an X-acto knife, or some other sharp pointed tool,
where I want to drill the hole. I then
drill a guide hole with a small bit, applying very slight pressure and letting
the heat that builds up on the point do the drilling. I use increasingly bigger bits finishing with
the correct size.
Countersinking
Acrylic – I decided to try this and it has worked beautifully
for me. I use a countersink bit in a “dog-leg” deburrer. I go slowly
and visually check the progress frequently for centering, as well as for depth,
with the screw or washer to be used. It is
a slow but safe and effective method, allowing you total control. I also slightly debur the opposite side of
the countersink hole. I believe there is
less tendency for it to crack this way.
Cleaning -
I have used Goo Gone for cleaning
acrylic windows and covers with great success.
It removes Sharpie reference lines, as well as masking and duct tape
adhesive. With masking and duct tape
residue, especially if it is large, I apply it generously over the area with my
fingertip, and as much as necessary, and let it soak. I then rub gently with the fingertips until
it dissolves, to avoid scratching the surface.
I then clean with soapy water, rinse with water and dry it with a soft
cotton (T-shirt) cloth. Do not let the
Goo Gone- adhesive mix start to dry out or the adhesive will tend to stick to
the surface again. If it dries out,
apply more Goo Gone and repeat the above process to dissolve it. Also, you may have to repeat the process,
depending on the amount of adhesive.
17. METHOD FOR FILLING STRAKE
END TO MATCH THE WING (1)
(2)
I did not want to attach the wings to the fuselage
while the airplane was inverted. So, I
transferred the contour of the wing to an acrylic poster face and made a very
slightly oversize template that I taped to the outboard end of the strake (1). I then filled the leading edge of the strake
to the contour of the template and let cure before sanding (2). I did the underside while the airplane was
inverted. I believe that after several
coats of primer buildup, I’ll get it to easily match the wing contour without
much sanding. This is a modified version
of
18. NOSE GEAR BUMPER
MODIFICATION (1) (2) (3)
(4)
While still building, I was told by
To me, this kept the rubber
of the shock compressed and did not
bring back its load absorption capacity.
Consequently, this would not make the nose gear drop or taxiing any
smoother either. In my opinion, even if
the metal plate would not bend, the shock absorption capacity of the original
part was minimal due to the load being spread over such a wide area.
I ran the part specifications and set up by Daniel and he believed
it to be appropriate, with an estimated safety factor of at least 2.5 to 3 on a
very rough landing. He also confirmed
that it should work better if installed vertically. Kevin was waiting for Daniel’s opinion, as he
was doing his annual and wanted to try an alternative to installing another
original part. He would be the first one
to test the modification. By the time we
ordered the parts, a couple of other builder-owners believed in the set up and
had joined. Kevin made a seat for it
against the canard bulkhead with microglass and installed it under compression
as planned. His comments follow.
“The airplane
feels perfect taxiing and landing. The
rubber shock shows no signs of deformity after several landings. It is still tight against the captivator.”
“Two landings
this weekend - both in x-wind conditions - no shimmy, no adverse issues.”
“I did taxi with
the thicker spacer and the shock mount performed flawlessly. The real
test will be how if feels during touchdown/landing.”
“I finally flew
today with the new shock mount. The shock mount worked perfectly.
All crosswind landings and touching down with a slight crab on one of the
landings. It’s great to know that if you don’t make a perfect landing,
you won’t bend a part on the airplane. For my installation, the 5/16”
spacer seems to be correct. This provided the shock mount to be installed
with good compression. Nothing more to report because everything worked
great..”
Picture (4) above shows my
final installation. The detailed description
and pictures of my installation process can be accessed on #2
of the Nose Gear section of the LANDING GEAR/ WHEELS/ AXLES page.
19. SUPPORTS FOR PRIMING
ELEVATORS (1) (2)
I made a support system to apply primer to the elevators. I screwed a couple of angles to my wing rack, with a separation ½ inch wider than the length of the elevators. I then used a couple of screws and castle nuts that I tighten by hand. It allows me to apply primer to both sides, by flipping it up or down.
20. MIXING CONTAINER FOR
PRIMER
I used PolyFiber UV Smooth Primer which requires mixing every cup of primer with 4 mL of crosslinker. For easy measuring and mixing of the primer, I marked one and two cup levels on a capped container with a permanent marker. After measuring the desired amount with the help of the markings on the container, I add the crosslinker with a small industrial syringe that is provided, cap the container, and use it as a mixer. This has proven to be a fast method to measure, mix and pour. I clean the container with water soon after every use to avoid the build up in the container or the threads.
The factory includes fixed aluminum tie-downs for bolting to the spar. I opted to design retractable tie-downs for myself. I have applied for a patent on the design and will no longer show them in this site. I will look into manufacturing and selling them in the future. You can contact me via email (WEBMASTER) for additional information.
22.
METHOD TO MAKE A CUSTOM
DIAMETER FIBERGLASS CYLINDER TUBE (1) (2)
(3)
My fuel servo intake is 3.875 inches in diameter, as
opposed to the more common three inches. Therefore, I had to make a four-inch round
fiberglass cylinder to use as the base for the flanges to attach the 4-inch
SCAT hose. I could not find an exact
diameter container around the house to make it, so I decided to make one
slightly larger and then adjust it to the right size. I used a 4-inch cylindrical plastic
container, covered it with duct tape, a thin film of petroleum jelly and laid
three layers of BID with peel–ply over it to make a tube about 5.5 inches
long. Once cured, I cut the cylinder lengthwise,
inserted it on the hose and made a mark where the ends overlapped. The overlap was about 3/8 inch. I removed the excess material with a sanding
disc on the air grinder so that both edges would align with each other and the
part would fit inside the hose. I
immobilized the joint with hot glue points on the outside and laid a 2-BID
strip with peel-ply on the inside of the cylinder for a perfect fit inside the
SCAT hose. Once cured, I finished with
one BID on the outside. II cut the
cylinder in sections, as needed, to fabricate the actual flanges for the runner
and the air filter box.
LINK TO
CONSTRUCTION IMAGES ON THE OFFICIAL VELOCITY WEBSITE
THIS SECTION
IS UPDATED REGULARLY.
PLEASE
REPORT ANY MALFUNCTION OR BROKEN LINKS TO:
© Jorge A. Bujanda / 2004-2011