FREE FLIGHT DURATION - 2003/06

THE NATIONAL CUP: Competition is an
integral part of the sport of Free Flight.
Contests offer a reason to build better
models, to trim them to fly as long as
possible, and to test our work against the
stopwatch. More important, contests give us
an excuse to gather in friendly competition.
Visiting with old friends and making new
ones is as important a part of the contest
experience as is the actual competition.
The National Cup provides yet another
reason for participation in Free Flight
competition. Patterned after the successful
America’s Cup for the Fédération
Aéronautique Internationale (FAI) classes,
the National Cup is a multicontest affair for
AMA Free Flight events sponsored by the
National Free Flight Society (NFFS).
The National Cup is based on a point
system. Points are accumulated based on
placings at various contests across the
country. At the end of the year, the flier
with the most points in a category wins the
National Cup in that category.
For a detailed set of rules, as well as a
list of National Cup contests, visit the
NFFS Web site at www.freeflight.org. You
will also find many other items of interest
on the Web site, including membership
information. If you are not already a
member of NFFS, join.
With hundreds of modelers participating
in the National Cup, the competition,
though friendly, can be fierce. In AMA
Power, Ronnie Thompson edged out last
year’s winner—Joe Clawson—510 points
to 487.
It was a come-from-behind finish for
Ronnie, who was 81 points down going into
the last contest of the year: the King Orange
International at Palm Bay, Florida. In the
AMA Gas events at this meet, Ronnie
ended up with two firsts and three
seconds—enough to pull ahead of Joe for
the year. Ronnie also won the 2002
National Cup in the new Classic Power
event for “locked-up” models without
autosurfaces.
In Rubber, Floridian Thurman Bowls
edged Chuck Marcos by seven points for
the National Cup victory. The Glider
competition was also close, with Thomas
Jones finishing 10 points ahead of Bill
Smead.
In Nostalgia Power Ron Sharpton
repeated his win in 2002, flying the T-Bird
design in a wide range of sizes. Jean
Andrews of Tucson, Arizona, won in the
Nostalgia Rubber event.
In the Junior National Cup, which
combines scores for all AMA events, Adam
June 2003 127
Louis Joyner, 6 Saturday Rd., Mt. Pleasant SC 29464
FREE FLIGHT DURATION
Ronnie Thompson won AMA Power and
Classic Power categories in the 2002
National Cup. See text for more winners.
Len Surtees’ Sting gliders span 18 to 24 inches. There’s even a 30-inch version. The 24-
inch uses hollow composite wing with chordwise carbon-fiber stiffeners.
New Ikara P-30 propeller assembly includes
molded plastic nose ring, nose block with
three screws for thrust adjustment.
128 MODEL AVIATION
Marsh won, with his brother Alex second.
To me, the best part of reviewing the
National Cup results was seeing that there
were 50 Juniors flying.
High-Tech Hand-Launched Glider: HLG
stands for Hand-Launched Glider. For as
long as I can remember, these were simple
things carved and sanded from solid balsa.
Building one—or a half dozen—resulted in
many balsa chips on the shop floor and a
good bit of balsa dust up your nose. (You
really should wear a face mask when
sanding.)
Occasionally a design would combine
sheet balsa and open tissue construction.
Some used a thin sheet-balsa upper surface
with simple ribs providing the curve of the
airfoil. The center portion of each wing
panel was cut out to save weight. Cleverly,
the scrap from the cutouts would be just the
right size for the tail. The whole thing was
tissue-covered.
Another technique, popular with larger
HLGs, was to use wide balsa leading and
trailing edges combined with a solid balsa
center-section and tip pieces. The whole
assembly was sanded to airfoil shape, balsa
ribs were added, then the wing was covered
with tissue.
Len Surtees down under in Australia has
been rethinking the HLG. In last year’s
NFFS Symposium he detailed two methods
for building HLG wings. One uses
insulation foam sanded to shape and
covered top and bottom with 1⁄2-ounce
fiberglass cloth and epoxy laminating resin.
A stack of telephone books is used to apply
pressure to the assembly while the epoxy
sets. (Len points out that although the
phone-book system works well for straight
or straight-tapered wing panels, a vacuum
bag is needed for rounded compound
shapes.)
To protect the front edge of the wing
from the inevitable nicks, Len incorporates
a spruce or hard-balsa strip along the
leading edge. For bending strength, he also
incorporates a carbon-fiber spar at the
wing’s high point.
Len’s second construction method is
considerably more complicated. He makes a
two-part mold of the finished wing,
complete with dihedral and any desired
washin or washout, then he places 2-ounce
fiberglass cloth coated with epoxy in upper
and lower molds to form the top and bottom
wing skins. Carbon-fiber tows placed every
30 millimeters (roughly 11⁄4 inches) provide
chordwise stiffening, much like
conventional ribs.
After the epoxy sets, a balsa spar is
added along with thick balsa ribs at the
center and dihedral breaks. Carbon-fiber
tows are added along the leading and
trailing edge, and the upper and lower skins
are joined, still in their respective molds.
The finished 24-inch-span wing weighs 24
grams.
Len has also experimented with
composite materials as a substitute for
conventional sheet-balsa tail surfaces. For
his Sting 24 stabilizer, he uses .045-inch
Rohacell foam sanded to shape and covered
top and bottom with 1⁄2-ounce fiberglass
cloth and epoxy. The assembly is then
vacuum-bagged.
The resulting stabilizer is 1⁄2-gram
lighter than comparable balsa pieces.
However, the weight-saving effect is
multiplied because the lighter tail needs less
nose weight to balance the model; the total
weight savings is approximately 2 grams.
All of this experimentation has paid off.
John Kamla’s Marie has 1⁄32 sheet tube with tissue inside and out.
Text has info on rolled balsa motor tubes, tailbooms.
Australian Len Surtees’ simple composite construction uses
lightweight fiberglass-cloth skins over a foam core.
More complicated hollow composite wing uses heavier fiberglasscloth
skins and carbon-fiber tow stiffeners instead of ribs.
June 2003 129
Len currently holds four Australian Indoor
records and three world F1N (Indoor
HLG) records.
Len is selling a number of HL and
Catapult Glider kits and components. Fullsize
plans are also available. For
information, contact Len Surtees, 10
Woodbry Cres., Tamworth, NSW 2340,
Australia, or E-mail lensurtees@
hotmail.com.
The 2002 NFFS Symposium is available
from NFFS Publications, c/o Robert
McLinden, Box 7976, Baltimore MD
21221. Ordering information is also
available on the NFFS Web site.
If you are interested in experimenting
with composite materials such as Rohacell
foam, carbon fiber, and lightweight
fiberglass cloth, Composite Structures
Technology is one of the best companies.
CST also sells epoxy resin and vacuumbagging
supplies. The Web site—
www.cstsales.com—offers information
about a variety of composite construction
techniques.
Rolling Your Own: A rolled-balsa motor
tube provides an elegant and more durable
alternative to a built-up fuselage that is
much easier to build. Total time, start to
finish, is roughly the same as for a builtup,
tissue-covered fuselage, but with a
rolled tube most of that time is spent
waiting for things to dry.
Instead of spending hours gluing in the
dozens, and sometimes hundreds, of
uprights required for a built-up fuselage,
roll the balsa tube and build the wing and
tail, then finish the tube. Here’s how.
Making a tube involves wrapping a wet
sheet of thin balsa around a form—usually
a piece of aluminum tubing from the
hardware store. After the wood dries, the
rolled balsa is removed from the form and
the seam is glued. Those are the basics;
beyond that, there can be a number of
finishing variations inside and out.
Figure out the diameter of tube you
want. If you are working with an existing
round front end and nose ring, that will
determine the diameter. If not, you have a
bit more flexibility. For a P-30-size model,
an outside diameter of roughly 1 inch is
Our Full-Size
Plans List has
hundreds
of models to
choose from.
See page 191
for details.
common. If you use 1⁄32 sheet balsa for the
tube, you would need a 15⁄16-inch-diameter
form to obtain the 1-inch outside diameter.
Unfortunately 15⁄16 inch is not a
standard hardware-store size, so your
options are to use 7⁄8-inch aluminum tubing
for a slightly undersize tube or 1-inch for a
slightly oversize tube. You can find the
aluminum tubing at most hardware and
home-center stores. Make sure you get a
piece that is at least 6 inches longer than
the motor tube. Deburr both ends of the
tubing.
Select a sheet of light to medium Agrain
balsa that is slightly wider than the
circumference of the form. You can
multiply the tube’s diameter by 31⁄4 or
wrap a thin strip of balsa around the tubing
and mark just beyond the overlap. The
main thing is to make sure the balsa is
wide enough to wrap completely around
the form with a slight overlap.
You need to treat one side of the balsa
sheet to keep it from absorbing rubber
lubricant. This side will be the inside of
the finished tube. You can use two or three
coats of clear dope, doped-on tissue, or
doped-on light fiberglass cloth. Each
option is stronger, heavier, longer-lasting,
and more trouble than the previous one.
It’s a matter of how long you think the
model will need to last and how much
weight you can stand.
Once the sheet of balsa is treated, it’s
time for a bath. Soak the balsa in a bathtub
or in one of the inexpensive plastic trays
used for soaking wallpaper. You’ll also
need some way to hold the balsa sheet
underwater. Any kind of waterproof
weights will work.
Fill the tub or tray with a couple inches
of hot tap water. (Some people recommend
using ammonia to soften balsa, but I have
read that it can break down the wood’s
cellular structure and weaken it. Besides,
the stuff smells.) Allow the balsa to soak
for roughly 15 minutes. Once the wood is
wet, it will start to curl. Keep rotating the
sheet so it stays completely wet.
Remove the sheet from the water and
pat it dry with a paper towel. Wrap the
balsa around the form, and hold it in place
130 MODEL AVIATION
Tell them you saw it in
“Modeler’s Mall”
with a few strips of masking tape wrapped
completely around the whole thing. Check
to make sure that the seam is straight.
Spiral-wrap with an ACE bandage. Pull
the bandage tight enough to make sure that
the balsa is snug against the form, but
don’t get carried away. Pulling the bandage
too tight will crush the balsa. You can
allow the wrapped tube to dry naturally for
a day or two. For safety’s sake, avoid the
temptation to stuff everything in the oven.
In addition to the risk of fire, there is a
good chance that the balsa will get too dry,
which can cause problems.
After the balsa is dry, unwrap the
bandage, remove the masking tape, and
slip the rolled balsa off the form. Slip it
back onto the form and add pieces of
masking tape crosswise every few inches
to hold things tightly together.
Use a sharp single-edge razor blade to
carefully cut along the edge of the
overlapping edge. I’ve learned that it is
much better to do this freehand, using the
edge of the balsa as a guide, than to try to
use a straightedge, which will invariably
slip.
Remove the tape and balsa trimmings.
Run a bead of Titebond or other slowdrying
glue along the edge of the seam,
and pull it together with tape every inch or
two. Make sure that the seam is tight and
that the balsa tube is maintaining a circular
cross-section. Use a minimum amount of
glue to avoid any oozing to the inside of
the tube. Allow the glue to set so that there
is no danger of it sticking to the form. Slip
the balsa tube back over the form, and let
the glue fully harden.
Sand the outside of the tube, remove the
form, and finish the outside with dope and
tissue. For an even stronger (and heavier)
motor tube, use lightweight fiberglass cloth
instead of tissue.
It is a good idea to add 1-inch-wide
strips of medium fiberglass cloth as
localized reinforcements at the front, rear
peg, and wing location. For localized
reinforcement at the nose and the rearpeg
location, add rings of 1⁄64 plywood.
Make these the same way you made the
tube: by wetting and rolling.
A tapered tailboom can be made in a
similar manner, using a tapered form such
as a pool cue. Cut the balsa blank to the
required taper, soak, and roll. I’ve found it
easiest to start wrapping the ACE bandage
from the little end. Working slowly and
carefully reduces the chance of splits.
For strength, it’s a good idea to add a
sheet-balsa former at the stabilizer
leading-edge position. You can install this
in the finished tailboom using a long piece
of square balsa. Poke the round former
into position, then glue it in place using
thin cyanoacrylate (CyA) glue soaked
through the sides of the tailboom. If
necessary, poke pinholes every 1⁄4 inch to
let the CyA flow in. Add a similar former
at the end of the tailboom.
P-30 Propeller Assembly: John Clapp of
FAI Model Supply is selling a nicely
made Ikara P-30 front end that includes
the familiar yellow propeller from the
Czech Republic, a nose block, and a nose
ring. The two-piece molded plastic nose
block is fitted with three small screws for
easy thrustline adjustment. The plastic
nose ring is designed to fit inside a rolledbalsa
motor tube.
For those of us without a machine shop
in the basement, this front end offers the
advantages of easy thrust adjustment and
a ready-made nose ring at an affordable
price. The complete front end, including
propeller and shaft, is $9.50.
In case you want to use one of the
other available P-30 propellers, you can
purchase the nose block and ring
assembly for $6.75. This also offers a
slightly less-expensive option in case you
want to use a different freewheeling
clutch. (The Ikara front end uses the
molded clutch ramp on the propeller for
freewheeling. Some people prefer to use a
ratchet-type clutch such as the Crocket
one, also available from FAI Supply for
$2.95.)
For more information, contact FAI
Model Supply at Box 366, Sayre PA
18840. You can also check the Web site at
www.faimodelsupply.com or E-mail
[email protected]. MA
June 2003 131

THE NATIONAL CUP: Competition is an
integral part of the sport of Free Flight.
Contests offer a reason to build better
models, to trim them to fly as long as
possible, and to test our work against the
stopwatch. More important, contests give us
an excuse to gather in friendly competition.
Visiting with old friends and making new
ones is as important a part of the contest
experience as is the actual competition.
The National Cup provides yet another
reason for participation in Free Flight
competition. Patterned after the successful
America’s Cup for the Fédération
Aéronautique Internationale (FAI) classes,
the National Cup is a multicontest affair for
AMA Free Flight events sponsored by the
National Free Flight Society (NFFS).
The National Cup is based on a point
system. Points are accumulated based on
placings at various contests across the
country. At the end of the year, the flier
with the most points in a category wins the
National Cup in that category.
For a detailed set of rules, as well as a
list of National Cup contests, visit the
NFFS Web site at www.freeflight.org. You
will also find many other items of interest
on the Web site, including membership
information. If you are not already a
member of NFFS, join.
With hundreds of modelers participating
in the National Cup, the competition,
though friendly, can be fierce. In AMA
Power, Ronnie Thompson edged out last
year’s winner—Joe Clawson—510 points
to 487.
It was a come-from-behind finish for
Ronnie, who was 81 points down going into
the last contest of the year: the King Orange
International at Palm Bay, Florida. In the
AMA Gas events at this meet, Ronnie
ended up with two firsts and three
seconds—enough to pull ahead of Joe for
the year. Ronnie also won the 2002
National Cup in the new Classic Power
event for “locked-up” models without
autosurfaces.
In Rubber, Floridian Thurman Bowls
edged Chuck Marcos by seven points for
the National Cup victory. The Glider
competition was also close, with Thomas
Jones finishing 10 points ahead of Bill
Smead.
In Nostalgia Power Ron Sharpton
repeated his win in 2002, flying the T-Bird
design in a wide range of sizes. Jean
Andrews of Tucson, Arizona, won in the
Nostalgia Rubber event.
In the Junior National Cup, which
combines scores for all AMA events, Adam
June 2003 127
Louis Joyner, 6 Saturday Rd., Mt. Pleasant SC 29464
FREE FLIGHT DURATION
Ronnie Thompson won AMA Power and
Classic Power categories in the 2002
National Cup. See text for more winners.
Len Surtees’ Sting gliders span 18 to 24 inches. There’s even a 30-inch version. The 24-
inch uses hollow composite wing with chordwise carbon-fiber stiffeners.
New Ikara P-30 propeller assembly includes
molded plastic nose ring, nose block with
three screws for thrust adjustment.
128 MODEL AVIATION
Marsh won, with his brother Alex second.
To me, the best part of reviewing the
National Cup results was seeing that there
were 50 Juniors flying.
High-Tech Hand-Launched Glider: HLG
stands for Hand-Launched Glider. For as
long as I can remember, these were simple
things carved and sanded from solid balsa.
Building one—or a half dozen—resulted in
many balsa chips on the shop floor and a
good bit of balsa dust up your nose. (You
really should wear a face mask when
sanding.)
Occasionally a design would combine
sheet balsa and open tissue construction.
Some used a thin sheet-balsa upper surface
with simple ribs providing the curve of the
airfoil. The center portion of each wing
panel was cut out to save weight. Cleverly,
the scrap from the cutouts would be just the
right size for the tail. The whole thing was
tissue-covered.
Another technique, popular with larger
HLGs, was to use wide balsa leading and
trailing edges combined with a solid balsa
center-section and tip pieces. The whole
assembly was sanded to airfoil shape, balsa
ribs were added, then the wing was covered
with tissue.
Len Surtees down under in Australia has
been rethinking the HLG. In last year’s
NFFS Symposium he detailed two methods
for building HLG wings. One uses
insulation foam sanded to shape and
covered top and bottom with 1⁄2-ounce
fiberglass cloth and epoxy laminating resin.
A stack of telephone books is used to apply
pressure to the assembly while the epoxy
sets. (Len points out that although the
phone-book system works well for straight
or straight-tapered wing panels, a vacuum
bag is needed for rounded compound
shapes.)
To protect the front edge of the wing
from the inevitable nicks, Len incorporates
a spruce or hard-balsa strip along the
leading edge. For bending strength, he also
incorporates a carbon-fiber spar at the
wing’s high point.
Len’s second construction method is
considerably more complicated. He makes a
two-part mold of the finished wing,
complete with dihedral and any desired
washin or washout, then he places 2-ounce
fiberglass cloth coated with epoxy in upper
and lower molds to form the top and bottom
wing skins. Carbon-fiber tows placed every
30 millimeters (roughly 11⁄4 inches) provide
chordwise stiffening, much like
conventional ribs.
After the epoxy sets, a balsa spar is
added along with thick balsa ribs at the
center and dihedral breaks. Carbon-fiber
tows are added along the leading and
trailing edge, and the upper and lower skins
are joined, still in their respective molds.
The finished 24-inch-span wing weighs 24
grams.
Len has also experimented with
composite materials as a substitute for
conventional sheet-balsa tail surfaces. For
his Sting 24 stabilizer, he uses .045-inch
Rohacell foam sanded to shape and covered
top and bottom with 1⁄2-ounce fiberglass
cloth and epoxy. The assembly is then
vacuum-bagged.
The resulting stabilizer is 1⁄2-gram
lighter than comparable balsa pieces.
However, the weight-saving effect is
multiplied because the lighter tail needs less
nose weight to balance the model; the total
weight savings is approximately 2 grams.
All of this experimentation has paid off.
John Kamla’s Marie has 1⁄32 sheet tube with tissue inside and out.
Text has info on rolled balsa motor tubes, tailbooms.
Australian Len Surtees’ simple composite construction uses
lightweight fiberglass-cloth skins over a foam core.
More complicated hollow composite wing uses heavier fiberglasscloth
skins and carbon-fiber tow stiffeners instead of ribs.
June 2003 129
Len currently holds four Australian Indoor
records and three world F1N (Indoor
HLG) records.
Len is selling a number of HL and
Catapult Glider kits and components. Fullsize
plans are also available. For
information, contact Len Surtees, 10
Woodbry Cres., Tamworth, NSW 2340,
Australia, or E-mail lensurtees@
hotmail.com.
The 2002 NFFS Symposium is available
from NFFS Publications, c/o Robert
McLinden, Box 7976, Baltimore MD
21221. Ordering information is also
available on the NFFS Web site.
If you are interested in experimenting
with composite materials such as Rohacell
foam, carbon fiber, and lightweight
fiberglass cloth, Composite Structures
Technology is one of the best companies.
CST also sells epoxy resin and vacuumbagging
supplies. The Web site—
www.cstsales.com—offers information
about a variety of composite construction
techniques.
Rolling Your Own: A rolled-balsa motor
tube provides an elegant and more durable
alternative to a built-up fuselage that is
much easier to build. Total time, start to
finish, is roughly the same as for a builtup,
tissue-covered fuselage, but with a
rolled tube most of that time is spent
waiting for things to dry.
Instead of spending hours gluing in the
dozens, and sometimes hundreds, of
uprights required for a built-up fuselage,
roll the balsa tube and build the wing and
tail, then finish the tube. Here’s how.
Making a tube involves wrapping a wet
sheet of thin balsa around a form—usually
a piece of aluminum tubing from the
hardware store. After the wood dries, the
rolled balsa is removed from the form and
the seam is glued. Those are the basics;
beyond that, there can be a number of
finishing variations inside and out.
Figure out the diameter of tube you
want. If you are working with an existing
round front end and nose ring, that will
determine the diameter. If not, you have a
bit more flexibility. For a P-30-size model,
an outside diameter of roughly 1 inch is
Our Full-Size
Plans List has
hundreds
of models to
choose from.
See page 191
for details.
common. If you use 1⁄32 sheet balsa for the
tube, you would need a 15⁄16-inch-diameter
form to obtain the 1-inch outside diameter.
Unfortunately 15⁄16 inch is not a
standard hardware-store size, so your
options are to use 7⁄8-inch aluminum tubing
for a slightly undersize tube or 1-inch for a
slightly oversize tube. You can find the
aluminum tubing at most hardware and
home-center stores. Make sure you get a
piece that is at least 6 inches longer than
the motor tube. Deburr both ends of the
tubing.
Select a sheet of light to medium Agrain
balsa that is slightly wider than the
circumference of the form. You can
multiply the tube’s diameter by 31⁄4 or
wrap a thin strip of balsa around the tubing
and mark just beyond the overlap. The
main thing is to make sure the balsa is
wide enough to wrap completely around
the form with a slight overlap.
You need to treat one side of the balsa
sheet to keep it from absorbing rubber
lubricant. This side will be the inside of
the finished tube. You can use two or three
coats of clear dope, doped-on tissue, or
doped-on light fiberglass cloth. Each
option is stronger, heavier, longer-lasting,
and more trouble than the previous one.
It’s a matter of how long you think the
model will need to last and how much
weight you can stand.
Once the sheet of balsa is treated, it’s
time for a bath. Soak the balsa in a bathtub
or in one of the inexpensive plastic trays
used for soaking wallpaper. You’ll also
need some way to hold the balsa sheet
underwater. Any kind of waterproof
weights will work.
Fill the tub or tray with a couple inches
of hot tap water. (Some people recommend
using ammonia to soften balsa, but I have
read that it can break down the wood’s
cellular structure and weaken it. Besides,
the stuff smells.) Allow the balsa to soak
for roughly 15 minutes. Once the wood is
wet, it will start to curl. Keep rotating the
sheet so it stays completely wet.
Remove the sheet from the water and
pat it dry with a paper towel. Wrap the
balsa around the form, and hold it in place
130 MODEL AVIATION
Tell them you saw it in
“Modeler’s Mall”
with a few strips of masking tape wrapped
completely around the whole thing. Check
to make sure that the seam is straight.
Spiral-wrap with an ACE bandage. Pull
the bandage tight enough to make sure that
the balsa is snug against the form, but
don’t get carried away. Pulling the bandage
too tight will crush the balsa. You can
allow the wrapped tube to dry naturally for
a day or two. For safety’s sake, avoid the
temptation to stuff everything in the oven.
In addition to the risk of fire, there is a
good chance that the balsa will get too dry,
which can cause problems.
After the balsa is dry, unwrap the
bandage, remove the masking tape, and
slip the rolled balsa off the form. Slip it
back onto the form and add pieces of
masking tape crosswise every few inches
to hold things tightly together.
Use a sharp single-edge razor blade to
carefully cut along the edge of the
overlapping edge. I’ve learned that it is
much better to do this freehand, using the
edge of the balsa as a guide, than to try to
use a straightedge, which will invariably
slip.
Remove the tape and balsa trimmings.
Run a bead of Titebond or other slowdrying
glue along the edge of the seam,
and pull it together with tape every inch or
two. Make sure that the seam is tight and
that the balsa tube is maintaining a circular
cross-section. Use a minimum amount of
glue to avoid any oozing to the inside of
the tube. Allow the glue to set so that there
is no danger of it sticking to the form. Slip
the balsa tube back over the form, and let
the glue fully harden.
Sand the outside of the tube, remove the
form, and finish the outside with dope and
tissue. For an even stronger (and heavier)
motor tube, use lightweight fiberglass cloth
instead of tissue.
It is a good idea to add 1-inch-wide
strips of medium fiberglass cloth as
localized reinforcements at the front, rear
peg, and wing location. For localized
reinforcement at the nose and the rearpeg
location, add rings of 1⁄64 plywood.
Make these the same way you made the
tube: by wetting and rolling.
A tapered tailboom can be made in a
similar manner, using a tapered form such
as a pool cue. Cut the balsa blank to the
required taper, soak, and roll. I’ve found it
easiest to start wrapping the ACE bandage
from the little end. Working slowly and
carefully reduces the chance of splits.
For strength, it’s a good idea to add a
sheet-balsa former at the stabilizer
leading-edge position. You can install this
in the finished tailboom using a long piece
of square balsa. Poke the round former
into position, then glue it in place using
thin cyanoacrylate (CyA) glue soaked
through the sides of the tailboom. If
necessary, poke pinholes every 1⁄4 inch to
let the CyA flow in. Add a similar former
at the end of the tailboom.
P-30 Propeller Assembly: John Clapp of
FAI Model Supply is selling a nicely
made Ikara P-30 front end that includes
the familiar yellow propeller from the
Czech Republic, a nose block, and a nose
ring. The two-piece molded plastic nose
block is fitted with three small screws for
easy thrustline adjustment. The plastic
nose ring is designed to fit inside a rolledbalsa
motor tube.
For those of us without a machine shop
in the basement, this front end offers the
advantages of easy thrust adjustment and
a ready-made nose ring at an affordable
price. The complete front end, including
propeller and shaft, is $9.50.
In case you want to use one of the
other available P-30 propellers, you can
purchase the nose block and ring
assembly for $6.75. This also offers a
slightly less-expensive option in case you
want to use a different freewheeling
clutch. (The Ikara front end uses the
molded clutch ramp on the propeller for
freewheeling. Some people prefer to use a
ratchet-type clutch such as the Crocket
one, also available from FAI Supply for
$2.95.)
For more information, contact FAI
Model Supply at Box 366, Sayre PA
18840. You can also check the Web site at
www.faimodelsupply.com or E-mail
[email protected]. MA
June 2003 131