Answer by Brett Jaffee
Gliders are planes that glide down to earth without power. A good example
might be a WW2 troop glider. It's not designed to catch or ride thermals and
climb, just to be released from its tow plane and glide down to earth. The
space shuttle in its landing mode would be another example.
A sailplane, OTOH, is designed to ride the wind and climb in the thermals and
other updrafts. In truth, just about any plane, even powered ones, can climb
in thermals and updrafts if they are strong enuf, but "sailplane" is usually
reserved for planes that are purpose-built to take advantage of this.
Answer by David Larkin
The chord is the distance between the front of the wing (the leading edge) and
the back (the trailing edge).
Answer by Bernard Grosperrin
measured on a line parallel to the fuselage..... and obviously a chord is
not a constant, it's just a value for a given point on the wing. Root cord
and tip chord can be quite different...
Answer by Jonathan Gogan
Imagine a line down the middle of the fuselage - this is called the water
line (because planes usedto be made by shipwrights - you live and learn)
Put the wing at an angle of about + 2.5 degrees to this; this is the
riggers angle, also called angle of incidence.
When the wind flows across the wing, relative to the chord line
(a line
across the centre of the wing from leading edge to trailing edge) it defines
the angle of attack. this changes all the time - if it gets too large
(greater than 15 to 18 degress) you stall.
The tail (horizontal stabiliser) is also at a small +ve angle compared to
the water line but not as great as the riggers angle! the difference in
the two angles, i.e. 2.5 for the wing and 1.5 for the tail, is known as the
decallage.
Answer by Robert Barkus
Flutter is where a control surface moves back and forth rapidly
without any actual input from the pilot. It is caused by any one of
several factors. The two most common are, 1) loose control linkages
2) excessive speed (for a given model/setup). The first is easy to
spot. Turn your tx/rx on. Move each surface by hand back and forth.
The servo should hold fairly well. If you can move the surface without
moving the servo you have too much slop. Flutter will happen very fast
(not always) and can quickly break parts like the stab and fin.
Answer by Phil Godwin
The event is a high frequency oscillation of the surface which can
sometimes be seen as a blur of the surface in a close flyby and can
usually be heard above the sound of the engine.
If you hear an unusual buzzing sound and there are no bees in the
vicinity then throttle back and land as soon as possible and check your
plane over. Look for any loosness or flexibility in the control
linkages, hinges broken or worn, or excessive torsional flexibility.
The cure can be as simple as adding additional hinges, using larger,
stiffer pushrods, eliminating clevis to control horn slop, etc. Or it
may require the rebuild of a surface or adding counterbalances.
Overpowering a plane can also cause you grief.
Answer by Dr1Driver
It will increase lift and drag, which will make the plane fly slower with the
same engine power. If this is what you want, you might want to consider
a large diameter/low pitch prop.
Say a 10-4 or 11-4 instead of a 10-6.
Answer by Arizona Chuck
When you have a warped wing you can't straighten it on a flat surface.
If you have a 1/2" warp you have to block it up so you have a 1/2" warp in
the opposite direction, then when it dries it will pop back to straight.
Answer by James G. Branaum
I have sprayed the entire wing with water and weighted it down for a few
days. Got to have a straight, flat surface, and two long hard surface items
to put on top of the spar and support the weight and another long hard item
to put on the T.E. that also will be able to support lots of weight.
Spray the wing down, block the spar in place and weight it, then block and
weight the T.E. in place. Try to get the T.E. flat (or all the standoffs
anchored to the table with weight) to prevent warping as the wing dries.
Answer by Edwin Smith
If weights and wetting didnt help over night, I would take the sheeting off
and do it over if its that bad. Better to sacrifice a sheet of balsa than
to risk a bad job. If its glued in really good, I would hack it out with
the scalple then use a dremil and various bits to remove the rest.
Answer by Gerrit Hiddink
If you've used a heat-shrinking cover, like Oracover, you can easily
remove warps by fixing the wing in the desired (warped if necessary)
position, and re-heat the cover. If the effect is not sufficient, then try
to warp it a bit more in the reverse direction. Be careful not to overdo
the "anti-warp"! Also, only do this if the other methods didn't work because
you will keep a certain tension in your wing between the balsa and the
cover. This tension may reduce the strength of your wing.
Answer by Dr1Driver
For a 2 meter glider, I'll go with 1/16" (1.5 mm, GH) unless you're planning to winch it,
then I might go 3/32" (4.5 mm, GH) on the inner 1/3 of the ribs.
Answer by Gareth Bannister
on my great planes spirit, it has 1/16" ribs (1.5 mm, GH). The wingspan is 78" which I
believe is classed as a 2m.
Answer by Chas L.
Both Andy Lennon (Model Airplane News, Nov. 96) and Paul
Denson (R/C Modeler, Nov. 95) recommend that the stab area
be approximately 20% of the wing area.
Answer by Pé Reivers
Nitromethane does two things
1) It contains oxygen in chemical storage, which can be liberated when
heated. This extra oxygen then can be used to burn extra fuel and thus
increase power. There is a need however to reduce compression ratio in the
engine when using much nitro (>15%)
2) Nitro in itself has low caloric values, but it has a very wide combustion
range when mixed with air. (1/1 to 1/5 by weight). Because of this wide
range, engines with a lot of nitro mixed in their fuel are less sensitive to
changes in fuel supply is in vertical manoeuvres and idle, so with less
nitro, you need to be more expert to tune the engine right.
Answer by David Larkin
The basic formula is equal parts ether, castor oil and kerosene plus 2% Amyl
Nitrate or Isopropyl Nitrate (IPN) ignition improver. Depending on the
engine, you can vary this. Stick to the above formula for a vintage
diesel. But with a modern diesel like the Irvine 40D or 20D you can drop
the oil content to as low as 20%. Take the ether content up to 35%, add
the ignition improver and the balance is kerosene. Basically you reduce the
oil content as you add the following feature in an engine:
Single Ball bearing,
Twin ball bearing
ABC piston/cylinder assembly.
Some people use automotive starting fluid instead of ether. It doesn't
contain 100% ether so increase the amount of it and use less kerosene.
It is possible to use old fashioned automotive mineral oil instead of castor
oil. Say SAE 40. But generally, castor is preferred.
Commercial model diesel fuels can be obtained from Aerodyne, FHS (Red Max),
Eric Clutton and Davis Diesel.
Answer by Joe L.
The major constituent of model airplane fuel is methanol (methyl
alcohol). So a typical RC fuel might be 70% Methanol, 20% oil
(synthetic or castor oil, or a combination of both), and 10%
nitromethane. If 0% nitromethane then you would have 80% methanol with
20% oil. (These are volume percentages, not weight!, GH)
Answer by Daniel Armstrong
Almost always, belt driven fans where tried but it is generally agreed
that there is an aerodynamic advantage having the motor in the duct to
reduce the cros-sectional area.
Answer by Dno1939
I wouldn't sand it at all! Try spraying the light blade with polyurethane
or laquer wood finish. I have used both, and haven't had any problem with fuel
attacking the finish. Alternately you could paint the tips with paint so
that they are eaiser to see when turning. Just put more paint on the light
blade.
Answer by Jack
When it is close to balance (by the way
I use Master Air Screw) I add white paint to the tip of the light end. That
helps me balance and gives me the visual white when the prop is running.
Answer by Bob Leserve
Go to http://www.printwares.com, it has a thrust calculator. Read
the manual 's thrust section for the approximate value of the weight an
engine can carry.
Answer by Gerrit Hiddink
Here's a table from a German postorder company `Conrad':
| Motor (in) | Motor (ccm) | propellor (in) | propellor (cm) |
| 0.5 | 6x3 | 15x7 | |
| 1.0 | 6x3/6x4 | 15x7/15x10 | |
| 1.5 | 7x4 | 18x10 | |
| .15 | 2.5 | 7x6/8x4/9x4 | 18x15/20x10/23x10 |
| .21 | 3.5 | 8x4/8x6/9x4 | 20x10/20x15/23x10 |
| .25 | 4.0 | 9x4/9x6 | 23x10/23x15 |
| .34 | 5.5 | 9x5/9x6 | 23x13/23x15 |
| .40 | 6.5 | 9x6/10x5/10x6 | 23x15/25x13/25x15 |
| .45 | 7.5 | 9x6/10x5/10x6/10x7 | 23x15/25x13/25x15/25x19 |
| .51 | 8.3 | 10x8/11x6 | 25x20/28x15 |
| .61 | 10 | 11x7/11x7.5 | 28x19 |
| .75 | 12 | 12x6/12x8/13x6 | 30x15/30x20/33x15 |
| .90 | 15 | 12x8/13x6 | 30x20/33x15 |
| 1.5 | 25 | 18x6/18x8 | 45x15/45x20 |
| 1.8 | 30 | 18x8 - 20x8 | 45x20 - 50x20 |
| 2.7 | 45 | 20x10 - 22x8 | 50x25 - 55x20 |
| 3.6 | 60 | 22x10 - 24x8 | 55x25 - 60x20 |
Answer by Gerrit Hiddink
This is also known as a `stator ring'. It modifies the
magnetic fields of the permanent magnets in the motor, giving it
more power (it'll also consume more current from your battery pack).
Answer by Paul J. Burke
If the wing is constant chord.. the c.g. for safe flight will be at 25% of
the chord. For more exhuberant flying, 30% will work...
Answer by David Larkin
If you are an unexperienced flyer, I suggest that you start by
balancing the plane so that it balances a quarter of the way back from the
front of the wing. Later you can balance it somewhat more towards 30% but as
you do so the plane will become more sensitive to elevator movement and may
eventually become unstable if you go too far.
Answer by Ezas
Here is just the thing you need. It is very typical for plans to give a
VERY conservative C of G setting.
http://www.palosrc.com/instructors/cg.htm
This link will let you calculate the distance from the leading edge at a
given % of chord length.
Answer by steinhau@earthlink.net
I would consider using the Panknin Wing twist formula available from the
B2 Streamlines web page.
Generally, you will enter parameters relating to the
geometry of your swept wing aircraft on the left side of the spreadsheet
and the computed parameters (including suggested CG) will be on the
right side of the spreadsheet. I have found this formula to be the best
predictor of proper CG on a tail less aircraft but CG is somewhat a
matter of taste depending on the stability margin you want to fly with
on your aircraft (beginners sometimes opt for greater stability and
experts generally like "hands off" approximately neutral stability. The
"stability factor" entry on the spreadsheet generally has a value from
.02 to .04 with .035 about right for most purposes as an initial trim
position.
http://www.halcyon.com/bsquared/Panknin.html
Answer by Ezas
The calculators mentioned in the question above do work if you put
in a negative number for sweep.
Answer by Andrus Kangro
You can do a "dive test".
That means - you set as much up trim as it takes, while still flying
smoothly. Then you make it dive at 10..15 degrees or so and then return
your sticks to normal position. If it levels itselt in 2..5 seconds,
then you have CG where it should be. If it makes it faster, then it's
too nose heavy and you should remove some weight. If it does not level
itself so fast or dives even more, then you should add some weight.
Answer by Kjell Aanvik & CDance7412
The fuel tank is normally located in front of the CG. A full tank will then move
the CG forward, an empty tank will move it rearwards.
If you balance your plane with a full tank, you're in for a suprise when flying
and emptying the tank.
You must balance the plane with an empty. You want the CG to be correct
when landing which will presumably be with the tank mostly empty.
Answer by Paul Wetherill
Moving your CG back will not decrease your sink rate. It will however, make
your model more sensitve in pitch. You can fly slower and the model will
send you a clear message when it contacts lift. Move it too far back and you
are likely to experience a "tuck under". Remember to adjust you declage if
you move your CG otherwise you will lose efficiency.
Answer by Michael Neverdosky
PPM (Pulse Position Modulation) has the information in the length of space between pulses
sent by the
transmitter. The length of space varies with the position of the stick
on the transmitter and is decoded into a PWM (pluse width modulation)
signal to drive the servo. The information is in analog form all the
way.
PCM (Pulse Coded Modulation) sends a digital word that has the information to be
decoded by the computer in the receiver. The information is in digital
(binary number) form during transmission and reception and is usually
decoded to PWM to drive standard servos by the receiver.
Answer by Gerrit Hiddink
Don't ask this question at the newsgroups ;)
There are a number of often-heard propositions that may or may not be true:
PCM is said to have a larger range, some claim about twice as large.PCM is said to be less sensitive to interference of other transmitters on
the same frequency.PCM has failsafe devices, which mean that your servos can enter in a
preconfigured position when the TX signal is absent (i.e. idle throttle,
a bit rudder/aileron, a bit down elevator)PCM is said to lock out the plane for 2, 5 or 10 seconds when even a
very small glitch occurs (1/8 sec)PCM is said to mask glitches so that you will never find onboard control problems,
until it is too late... (you could install a glitch counter)
Answer by Gerrit Hiddink
They're both techniques to modulate a low frequency signal (LF) onto a
high frequency (HF, eg. 35 MHz) carrier signal. Frequency Modulation, or
FM, creates very small deviations in the frequency of the HF carrier. Amplitude
Modulation, or AM, creates very small deviations in the amplitude (signal
strength) of the HF carrier.
Answer by Cliff Griffin
The servos are supposed to get a block-shaped pulse with a fixed frequency,
with the duty cycle varying to control the position. A 1-2ms
pulse every 20ms (which corresponds to 50 Hz) will give you full travel,
with 1.5ms being in the
center, 1ms at one extreme and 2ms at the other.
Answer by Gerrit Hiddink
A servo works using a feedback loop. This goes as follows:
the IC's in the servo translate the pulse width into a voltage,
probably using a capacitor: the longer the pulse, the higher the
voltage (there's more time and energy to charge the capacitor, so
that its charge will get higher).
Then there's a potentiometer connected to the axe of the servo. This
This potentiometer consists of a grafite strip and a piece of metal
that glides over it. The more the servo turns, the more the metal
glider moves towards one side of the strip. If the servo turns the
other way, then the glider moves to the other end of the strip.
One end of the strip is connected to the 0 volt power lead, the
other is connected to the 6v (or whatever) power lead. The wire
connected to the metal gliders gives a voltage of 0 volt if the
glider is at the 0 volt end, it will give 6 volt if the glider is
at the 6 volt end, and it will give anything in between (linearly
if it's a linear potentiometer) if it's anywhere in between.
The voltage of the pulse width to voltage circuit and the voltage
of the potentiometer are then compared. If the pulse width circuit
gives a low voltage, say 1 volt, and the potentiometer is in a
position where it gives 5 volts, then the motor is switched on
so that the glider of the potentiometer moves towards the 0 volt
side. The circuitry inside the servo keeps monitoring both voltages,
and will keep the motor running until both voltages are the same.
The potentiometer (and the servo's arm) are now in a position that
represents 1 volt, which is almost in the utmost position.
If the stick is moved to the center, then the pulse width gets
larger, the voltage on the capacitor also gets larger, say 3
volts, and the circuitry that compares the voltages sees that
now the voltage of the capacitor is larger than the voltage of
the potentiometer, so that the circuitry will turn on the motor
to run into the other direction. The potentiometer will then
move towards the middle, until it is at the 3 volts position,
after which the motor will be turned off.
Answer by Gerrit Hiddink
The antenna is designed to pick up radio waves. So first let's translate the
frequency of a radio set into a wavelength. This is done with the formula:
l = s / f with l the length in meters, s the
speed of radiowaves through air (which is approximately the speed of light, which is
300.000 km/sec) and f the frequency in Herz. So a set with a frequency
of 27 MHz transmits waves of 300.000.000 / 27.000.000 = 11.11 meters. An antenna
needs to be either a full wavelength, or a half wavelength with groundplate. Such
wires would be way too long. So your receiver pack includes coils, which may be
seen as rolled-up antenna, to artificially reduce the needed length of actual wire.
So, the length of the actual wire plus the coils in the receiver pack matches the
frequency of the set. To know what length the coils in the receiver pack match,
you would have to reverse-engineer it. Other than that, or measuring the length of
an identical receiver, there's no way to know what
length of wire needs to be with a particular receiver. So it may be wise to measure
it before you lose some length...
Answer by Dick Pettit
You can reverse a servo quite easily, if you have expertise in
soldering. Use a small iron, maybe 15-20 watts with a very fine point,
and use rosin core solder only. Get help from someone who has
experience.
Open the servo and reverse the 2 wires going to the motor. If the motor
is connected directly to the PC board, close the servo up and buy a
reverser.
You also have to swap the 2 outside wired on the potentiometer, which is
WAAAAY down inside the servo case. There are 3 wires, just reverse the
outer 2. If you don't feel comfortable doing this, buy a reverser.
If you completed the 2 wire mods, take your soldering iron and etch a
big "R" into the case. This'll remind you that this servo is reversed.
Answer by Kirsch
You buy a servo reversing harness, which is just a short extension with
a small bit of electronics that reverses the signal to the servo. Simply
reversing polarity is a bad thing, or so I've been told.
Answer by Murray Lane
NiCad battery packs are made up of individual NiCad cells. Each cell generates a
voltage of 1.1 volts to 1.5 volts depending on
charge and other factors. The pack voltage is simply the sum of the cell voltages.
The capacity(C) of each cell depends on the size
and formulation of the cell. Normally we use AA (or, perhaps more often, sub-C, GH) size cells which have a
capacity of 500 to 900 milli-amp-hours (mAh). All the cells
in a pack MUST have the same capacity. The capacity of the pack is the same as that for an individual cell.
Answer by Red Scholefield
The numbers obviously translate into mAh's, e.g. a "KR-1200AAE" is a 1200 mAh cell.
From the Sanyo Nickel Cadmium Data Book (98.8. 5.000)
High Cpacity Batteries - E-series/U series
Fast Charge Batteries - R-Series
High Temperature Batteries (Standby use) - H-series
Heat Resistant Batteries (cyclic use) - K-series
Extend Service Life Batteries - C-series
Memory-backup Batteries - S-series
Standard Charge (N-series):
N-270AA, N-500A, N-600AA, N-1000SC
Standard Charge (KR-series): KR-1300SC, KR-1500SC
High Capacity (E-series/U-series):
KR-600AE, KR-800AE, KR-1000AAU, KR-1100AAU, KR-1200AAE, KR1200AUL, KR-1500AUL, KR-1400AE, KR-1700AU, KR-1700AE, KR-1700SCE, KR-2300SCE
Fast Charge Batteries (R-series): N-500AR, N-1000SCR, N-1250SCRL, N-1300SCR, N-1700SCR, N-1900SCR
Extended Service Life Batteries (C-Series
(Note: Specs for these cells are nearly identical with N-series with the
exception that they have slightly higer internal resistance, suggesting
that a different (longer life) separator may be employed): N-250AAAC, N-270AAC, N-500AC, N-600AAC, N-700AAC, N-600AACL, N-700AACL
The cell diameters as see as AAA, AA, A and SC in the above designations.
Cell lenths vary with capacity.
The others (H/K/C/S) series are not generally suited for our application).
Sanyo date codes:
fist character, year W=92, X=93, Y=94, Z=95, A=96, B=97, C=98, D=99 and so
on. second character = month A=Jan, B=Feb, C=Mar..... L=Dec
ZF=95 June
Cells manufactured on Dec 7th, 1999 will carry the date code DL
Answer by Cliff Griffin
The 8 cell pack will give your more power at full throttle, and if held
at full throttle for the same amount of time, then less run time. At
full throttle, 8 cell packs run a higher current, and therefore run down
faster if you run them at full throttle. If, however, you use a lot of
throttle management, and reserve WOT for rare situation, then it will
last just as long, maybe even longer, than a 7 cell pack.
Answer by Robert Suding
Your NiCad batteries are rated at room temperatures, 68 degrees. At 20
degrees I found that I had lost 20% of their capacity. For example, a 1000
mah pack at 20 degrees F measured 800 mah cycling on my Ultimate
Charger. In terms of flights, If you take 5 flights in the Spring & Fall,
take 4 flights in the Winter.
Answer by Red Schonefield
The capacity delivery of alkaline cells is discharge dependent.
You can get all the details for alkline performance including capacity
delivery at different loads at:
http://www.duracell.com/OEM/index.html
For openers however you are looking at the following capacities. Note,
these are to a cut off voltage of 0.8 volts/cell.
| Cell type | Capacity | Discharge current |
| AAA | 1150 mAh | 12 mA |
| AA | 2850 mAh | 28 mA |
| C | 7800 mAh | 60 mA |
| D | 15000 mAh | 115 mA |
Answer by Red Schonefield
It is a product of the
reaction of KOH (Potassium Hydroxide, GH) with the wire (cuprichydroxide Cu(OH)2 - dark blue
crystals (note the blue stuff formed in connectors associated with black
wire problem), insoluble in water. The KOH is actually driven by the
potential across the wire. you can duplicate the effect by immersing a
length of lamp cord in a 30% solution of KOH and connecting a voltage
source at the other end. Use another identical piece of wire with no
voltage source. You will note that the KOH creeps along one wire only, not
equally along the other three.
This is why you must remove exhausted batteries from your transmitter and receiver.
Answer by Gerrit Hiddink
You can find a battery tutorial here: http://www.slewin.clara.net/elec/tbatt.htm
or alternatively you can find a FAQ here: http://www.thiel.com/damien/newton_battery_FAQ.html
Answer by Spadman
Without getting into a highly detailed description it is used to
eliminate noise transferance while providing control over current.
This is achieved by eliminating the hard wire electrical connection
inside the controller and replacing it with a opto coupler. The
sitching is then done by controlling a photo diode with a LED emitter
(sort of like a light activated switch). This eliminates most
possibility of electrical noise. Most comonly refered to as "opto
isolation" It is found in better circuits and extensively used
throughout the electronics industry in general. --
Answer by Gerrit Hiddink
Look at the following urls:
http://www.scalecombat.com for 1/12 scale combat planes;
http://www.starcadplans.net for the famous
StarCad plans repository;
http://www.jps.net/hemanlee/Freeplans.htm for some simple plans;
http://www.stud.ntnu.no/~thomanie/drawings.shtml: the Balsadust
homepage
http://www2.hunterlink.net.au/~ddtd/models/plans.html: Thomas Delgatto's
plans
Answer by Gerrit Hiddink
You can use a number of CAD tools to print .dxf files. The program has to be able
to print a large drawing onto a number of A4 sheets if you do not have an A0 printer
or plotter. The program I use is IMSI TurboCAD 2D, available for free at
http://www.turbocad.com.
Answer by Spadman
You can xerox (parts of) the plans and put them face-down on the wood. Then
iron the paper so that the drawing is transferred to the wood. Aside from the
fact that they are a mirror copy, there will be a
slight size difference. I overcome this by copying the original at 99%
or making sure that I always cut to the inside of the line. Of course
when doing large pieces like a fuse side this won't help much, but for
most sport planes the size difference is of little concern. You can check
with a ruler if the size hasn't been changed.
Another old favorite method is to tape the plan to a window and then a
piece of tracing paper to the plan. Light coming through the plan will
allow you to make really good tracings of the big pieces, for the stick
and cut method of duplicating parts. Just make sure it's not night.
Answer by Lars Steffenrem
I use to glue the photocopy directly to the balsa/plywood using a gluestick.
It usually comes off quite easy, and if not, soften the paper with a damp
rag and scrape it off.
Answer (author unknown)
It's not necessarily linear. It's more of a judgement call. For example, if
the 40 sport model has a 1/4" square spar, and the giant scale is double the
wingspan, it e probably doesn't have a 1/2" spar. Sheeting will usually not
double, but will increase by 1.5. Take a look at the plans for similar-sized
planes and use them as a guideline.
Answer by Cain Fly
Apply your "yellow" resin glue, but leave the corners and some inside
spot/s bare, and for big doublers a few spots along the edges. Join the parts
and rub them together. Pull apart and on the spots still left bare, apply a
drop of thick CA. Rejoin and QUICKLY align, then press for a few seconds. You
now have a joined unit that allows you to continue without clamps/pins, etc.
and the "laminated" unit strongly resists any warping that the water based glue
might induce.
Answer by Roger Neal
Here's a link on fiberglass mold making.
http://www.cstsales.com/fiberg0.htm
Answer by Craig Greening
If you have any spare foam you could enlarge the hole to a uniform shape and
insert a new piece then resinstall the dowels, failing that you could try
some expanding foam and carve/sand it to shape after it sets. Check the
compatibility of the expanding foam with your wing before using.
Answer by J.D.
and bear in mind that most, if not all, expanding foams are a one-time use. At
least the ones I've come across were.
Answer by Dave Mosley
most epoxies can be 'thinned' by heating - mix in paper/wax dixie cup and
place on a "coffee cup warmer" or similar insulated heating device. longer
cure time epoxies allow time for heating.
I use 1 hour epoxy, heat it up to about 150 degrees F. this tends to reduce
the viscosity by about 50%, and makes spreading a thin layer possible.
Answer by Icrashrc
Polyurathane glue is the best i've found for foam. It expands as it cures and
make the whole area around the joint stronger. As an example I just recently
glued a 1/4" hardwood dowel thru a piece of 1" white foam. I didnt realize how
crooked I had drilled the hole until after the glue was set and I went to
assemble the parts. I actually broke off the dowel by hand without hurting the
foam it was glued into. Look in a good hardware store or somewhere like home
depo or lowes for it.
Answer by Gerrit Hiddink
You can download plans for building your own
foam cutter here: http://gallery.uunet.be/david.claeys/
Answer by Jim McIntyre
You need a proper iron, a clothes iron is too heavy, bulky and
hard to control heat correctly. You can use a heatgun especially around
compound curves like wingtips etc. It's not absolutely necessary though.
You would also need sharp razor blades or a trim cutter. A sheet of glass
is also handy for cutting pieces to fit or tacking colors together.
The process of covering works as follows:
Prepare the surface (sand, sand & more sanding). Clean with tack
cloth.Prepare a clean area to work.plan your covering order, paying special attention to material overlap. cut pieces oversize Remove backing!check iron for correct heat (process explained on film instructions) tack around perimiter then seal around perimeter (never tack to inner
surface or it will wrinkle when you shrink) Cover all surfaces b4 shrinking. Shrink opposing sides evenly,
periodically checking for warps and heating opposite side to remove.
Above all, keep everything clean. Use a sock for the iron and change it
often.
Answer by Andrew E. Mileski
Check the Topflite (Monokote)/Coverite (Micafilm)/Carl Goldberg
(Ultra Cote) web sites. At least one of them has step-by-step
instructions and pictures for covering a wing. You might also
consider buying the book "There Are No Secrets" by Higley.
Don't try to cover using a single piece. Wings: bottom, top.
Fuselage: left, right, top, bottom.
It doesn't hurt to leave a small 1 inch gap near a center edge, so
that air can escape while shrinking the rest. Seal this area last.
Use a soft 100% cotton cloth to gently press the heated film onto
the structure.
With a bit of heat, and some effort, you can always remove the
film and start over. Though I recommend trying to get it right
on the first attempt!
Answer by John Hawkins
If you want to save the weight of all the adhesive on a film
that is not used to actually stick it down, try Litespan or Micafilm.
You apply the heat activated adhesive only where you want it and I
think it too is lighter than what is used with the self-adhesive
films. Balsarite and Balsaloc are two adhesives. Litespan is by
Solarfilm and Micafilm I think comes from The Great Planes group of
companies. Balsarite is readily available. I believe Balsaloc comes
from Solarfilm. It's a water based product while Balsarite is solvent
based.
Answer by Fritz Bien
| covering | color | weight [g/ft^2] | comments |
| Monokote | red | 5.8 | |
| "" | red | 7.1 | '71 |
| "" | white | 7.3 | '90 |
| "" | black | 6.0 | '85 |
| "" | yellow | 7.5 | |
| "" | platinum metallic | 6.0 | |
| "" | red transp. | 5.5 | '88 |
| "" | orange flour. | 9.4 | |
| Ultracote | dark red | 8.5 | |
| Micafilm | yellow | 4.0 | needs balsarite |
| "" | red | 4.0 | "" |
| "" | red | 3.4 | '81,"" |
| "" | pre primed | 3.9 | "" |
| "" | white transp. | 2.2 | may(?) block radio signals (careful w/that antenna) |
| Sig Koverall | white | 4.3 | nd dope/paint |
| Sig Supercote | silver | 4.8 | |
| Esaki Lgt Silk | clear | .97 | nds care |
| 5/8 glass/superpoxy | clear | 3.9 | nds filler,color |
| jap tissue | yellow | .65 | pre-colored |
| Spraylat paint | 4.5 | water-based epoxy, 1 ml thickness | |
| clear nitrate dope | 1.0 | 2 coats thinned 50-50 | |
| dope, gloss finish | 7.0 | 8 clr, 4 color, 1 clr | |
| dope, grain showing | 2.0 | over silk | |
| Ultracote Plus | Pearl Yellow | 8.2 | .0022 thick, self stick |
| Ultracote | Cub Yellow | 6.6 | .002 thick |
| Transp. Ultracote | Yellow | 5.0 | .0015 thick |
| Transp. U'cote Lite | Red | 3.4 | .001 thick |
| Polyester Dress | Any color | 4.2 | req's Balsarite & Lining "Polypuff" 2+ coats of dope |
| Coverite Space Age | White | 10.4 | Pre-painted w/heat act. adhesive |
| Litespan | White | 2.6 | needs balsaloc/balsarite Model Masters (Testors) flat enamel over polyester fabric and 2 coats 50-50 dope: |
| Polyester Fabric | 4.4 g/ft2 | ||
| Sig Nitrate Dope, 2 coats, 50-50 | 1.0 g/ft2 | ||
| Enamel, 1 coat, Olive Drab | 3.5 g/ft2 | ||
| Enamel, 2 coats, Light Sand | 4.2 g/ft2 | (very light secondcoat) |
Answer by Brian Felice
Might be laminating film. This stuff is nearly the same thing as the hobby
coatings; polyester film with an adhesive on the back. It comes as thin as 1.5
mils (0.0015 inches) and heat shrinks just like the real stuff. Available at
most large office supply houses or by mail order. Cheap too, about $.10 / foot
for a 25 inch wide roll.
Answer by Pé Reivers
Silk was, and still is an unsurpassed covering material.
What you need, is a silk with an open structure, not the tight-woven stuff.
Model shops still sell Japanese silk, especially for models, but you can use
any silk you can find that fits weight and structure requirements.
The open weave is required for the shrink dope to do it's job properly.
First dope all contact surfaces and sand smooth with fine emery, dope again,
and run your fingers over it. There should be no fibres sticking out
anywhere. They will snatch the silk and spoil your job. Non-shrinking dope
may be used for that. You may want to mix in some talcum powder to fill
small indentations, like wood grain etc.
Cut and Lay out the patches of silk that you need, wet them one by one as
you work. Dry out excess water between towels.
Apply the patch to the structure. It will stick because it is moist. Smooth
it and apply dope to all parts that have structure underneath. The dope will
turn white, but not to worry, that will go away in subsequent coats. As the
silk dries, it will tighten.
After all patches have been applied, let dry. Then apply thin coats of
shrinking dope; do not rush. Each subsequent coat will fill the weave more,
and tighten the silk like a drum-skin. Coats will be dry before you reach
the end of one job, be it wing or fuselage, so there is no need to stop
working.
If you do stop, your brush may harden between jobs, just leave them a while
in the dope and it will be soft again. I use a flat 1.5" very soft brush.
Nice thing about it is, that you can dope on patches for repairs, tear off
parts of the silk and dope on new covering at wish.
Normal enamels do not adhere well to dope, unless you prime coat with an
automotive wash primer. Spar grade (cellulose based) paint (the ones that
can be rubbed to a gloss) works great.
You will find that it is easy to do, looks good, is easy to repair and lasts
very well.
Answer by David Larkin
One problem when using silk is that the dope may run through and collect in
unsightly lumps on the underside. To avoid this, many British 'vintage' flyers
use the 'meniscus' method. They don't brush directly on the silk but on to a
piece of silkspan tissue which they draw across the surface as they proceed.
Answer by Joe L.
Look here: http://www.top-flite.com/monokote/monoinst1.html
Answer by Dr.1 Driver
Get Higley's book, "There Are No Secrets". It's a good book on covering.
Answer by sport_pilot
Assuming you are covering with a plastic film. Any good primer or
sanding sealer would work. Or dope with talc powder added. Or go to
the hardware store and buy a can of Parks sanding sealer. It is the
same thing as nitrate dope with fillers added. If you are painting
then you need a primer or sanding sealer compatable with the paint you
will use.
Answer by Dno1939
Try dampening the wood with a wet paper towel or rag to raise the grain, then
cut it off with steel wool.
Answer by Dennis Adamisin
If its just the "normal surface fuzz that balsa has, rub it with a piece of
foam rubber, like you were sanding it. I read that in a magazine once and
it works like crazy. It definitely improves the bond of the covering too.
Answer by Brett Jaffee
Fiberglassing over monokote would most likely not work well at all. For that
matter, fiberglassing an EPP plane for this reason doesn't make a lot of
sense. EPP is so great because it can absorb punishment by flexing or
crushing, then bouncing back. The intent of fiberglassing is usually to add
a hard, protective shell, which would defeat the purpose of the EPP (the glass
would probably crack on the first impact anyway, since its on top of a
flexible surface).
You would be much better just adding some clear packing tape to protect the
bottom.
Answer by Edwin Smith
Do the epoxy glass method and you wont have any problems. I've done a fair
amount of epoxy glassing to make cowls. Its really pretty easy. Especially
if your going to leave the foam inside and it sticks pretty good to kote
type coverings.
Answer by MSu1049321
if you're going to glass foam, be sure it's epoxy fiberglass and not polyester
resin... that's the stinky kind that tends to eat foam.
Answer by Ton Jaspers
Rudder only control works well with a di or poly hydral wing.
Turning a straight wing design is hard to do with rudder only. A
straight wing is less stable, it does not automatically level like a
poly.
On the other hand a straight wing gives much better performance.
So, a high performance design will have straight wings and need
ailerons.
Answer by Doug Hoffman
I agree that in many conditions a non-aileron glider can perform thermal
turns well. In other conditions, such as gusty winds or "violent"
thermals that can kick your glider around, ailerons provide superior
roll control. Decouple the rudder and ailerons and, with
practice, your control over the ship in turns is much better. Very
flat,slow turns or extremely banked tight turns. But if
you aren't trying to optimise and are just wanting
to fly around, then if you prefer no ailerons by all means don't
use them...
A flat winged glider will also land better, especially in a crosswind.
The poly ship gets tossed around more with its "ears" sticking up.
Answer by Alton
Most people quit flying at the rated voltage (4.8 and 9.6). What really
helps is to discharge the batteries at a constant rate and note the
batteries performance. Nicad voltage will drop rapidly when the cells are
exhausted without warning. This is the reason for stopping at the rated
voltage. It is still helpful to know the characteristics of YOUR batteries.
As batteries begin to need replacing, the voltage at which beyond that the
battery will be exhausted begins to increase.
Answer by Gerrit Hiddink
No you can't! If you cut off, say, 10%, then the reception will be a lot
worse than 10% decrease. The length of the antenna is tuned to the frequency of your
set, so if you modify the length, it won't fit the frequency anymore. The best
layout of the antenna is a straight line, even if this means a dangling wire
at the tail of your plane...
Answer by Plane Guy
1. Air pressure falls with altitude, so the air entering your
carburetor is less dense at altitude, therefore you'll need a slightly
leaner mixture (i.e., less fuel to mix with the reduced air in order
to achieve the proper mixture ratio). 6K-7K altitude is right up there
- I'm sure you'll have to go slightly leaner.
2. Your airplane will have to achieve a higher groundspeed to get the
reduced amount of air at that altitude to flow over your wing and
produce enough lift. Expect longer time to get on the step, and a
longer takeoff run and shallower climbout angle. Please see the Koch
chart at this URL:
http://cyberair.com/tower/faa/app/p8740-2/p8740-2.html
Please also note that your airplane will appear to stall at a higher
speed at that altitude. Its stall speed isn't really higher - it's
just that the air is thinner and you need to move through space faster
to get enough reduced-density air over your wings to sustain flight.
3. A lower-pitch prop will improve thrust at the lower airspeeds
associated with takeoff and landing, but expect a slightly lower
cruise speed. It should also improve climb angle. Not sure about the
effects of nitro (seems like if your engine is happy with 5%, I'd stay
with 5%, but that's just a gut feel and not true knowledge)
Answer by Joel
It should look like an L. From the bottom, it should be about a 1/4" inch, and
the length should be about an inch. This sould work good. The material should
be music wire. I would use 1/16" (1.5 mm, GH), that should probably work. If you could
bend something a little thicker, then go ahead. Make sure it is securely
mounted to your plane. There is about 10+ lbs. of pull on the histart, so
maybe put a plywood base and epoxy the hook to that and secure to your plane
since it's a foam plane. I would put part of the wire going into the foam and
use a lot of duct tape to hold it. It may look crude, but hey! It works!
Answer by Howard Lute
The towhook should be located at the Centre of Gravity, or
slightly (1/4 - 1/2") forward of the CG.
Answer by Jeff Reid
Your models CG may be a bit
too far forwards which requires more up trim. This makes the model
"speed" sensitive. At higher speeds, like during a launch, the
model will want to pitch upwards (nose up). You can leave the
trim as is and feed in some down elevator to compensate for
this effect. During the up-start swing, tension in tubing will
decrease along with speed, and you can reduce the amount
of down elevator, usually when the tow line passes 45 degrees
or so.
The other fix is to trim you plane to be more neutral (CG further
back, less up elevator trim). This will make it less speed
sensitive, but you may still need to feed in some down elevator
during launches. It's a compromise between how it glides and
how it launches.
Another option if you have a computer radio would be to program
a "launch" switch to feed in some down elevator during up-starts.
One other option is to move the towhook even
more forwards to compensate for the pitching up at speed.
Answer by Jeff Reid
My preference for line to tubing length ratio is 3.5 to 1. For example,
with 25 feet of tubing, I would use 87.5 feet of line. I pull back
300% to 350% depending on conditions and weight of glider. In this
example case, (25 feet tubing), I'd pull back 75 to 87.5 feet.
With 50 feet of tubing,
I'd use 175 feet of line (40 pound test monofilament fishing line).
I pull back 150 feet (300% strain), to 175 feet (350% strain) depending
on the conditions. This setup would require 375 to 400 feet of space
for a full launch.
Answer by Tom Rent
You have to go to a Starter Rebuilder shop in most areas, not a parts store.
I have found them at parts stores but they charge too much in my opinion.
Starter rebuild shops know what they are doing and can make up what you
need. The first time I went to a starter shop to ask on these they knew
exactly what these were and had several on the shelf to sell to me. The most
common is the #3136 as described below. It is used on some front-end plow
systems to lift the blade so they need to keep some in stock. I opted to
have one made up with four 6 volt coils. See below:
RC Soaring Ford Long Shaft Motor types
SPORT: 12 Volt, 2 Windings: Rebuild #3115 or #3117. Original #'s were SA
519 and SA 622. [Application: Average user]
BIG SHIP: 6 Volt, 2 or 4 Windings (run on 12V): Rebuilt #3109, #3110, or
#3112. The Coils are Heavy Duty and when run at the higher voltage it does
induce more stress so rebuilding every few years might be
necessary.[Application: Contest winch ....get's hot so you need to cool it.
Consider buying ball bearing end plates] These one also eats batteries.
BEST BUY: 12 Volt, 4 Windings : Rebuild #3136 (Original # C 3 NF 11001C or
C 3 NF 11002C.
Make sure you have one with a 5.75" shaft as this fits most drums that are
available. There are 5.25" shafts around. Make sure the shaft is
straight too.
As for what vehicles used these originally, I am not 100% sure but I did
hear at one time they were used in 1963 Ford trucks, but don't quote me on
that.
Most Starter shops can make up what ever you want as the coils and cores can
be mixed and matched. I've been able to get these for between $40 and $70
depending on what work they need to do to get the one I want put together.
For the recreational flyer, the BEST BUY is a solid care-free configuration.
I fly the BIG SHIP configuration and do have some heat problems on hot days
with heavy ships and heavy usage ..... even had one cease up due to heat.
Answer by Ingo Donasch
Use 40-50mm diameter and choose a drum as long as possible to avoid excessive
buildup of diameter at the top of the lauch. (our winch has 50mm and it seems
almost too much). f3B winches have 40mm.
Don't forget the brake, it's very important. The pictures give in the urls below
should give an impression
how to attach the brake. duplicate the brake lever as close as possible to these
pictures.
if the angle and length is not right (+- 0.5in!) the brake does not work
properly.
I needed an additional 1oz weight on my brake because I didn't copy that winch
excactly.
http://asterix.specs-usa.com/Winch-drum.jpg
http://asterix.specs-usa.com/Winch-motor.jpg
the pulley weel for the brake is from ace hardware.
the line is braided nylon 170lbs (or better should be, the line you see on the
picture is way too heavy) and 125lbs line snaps to often.
Mount the turnaround on a pole that it is 2-3ft above the ground. this reduces
drag and
the line lives longer. if you can also mount the winch 1-2ft above the ground
that would even be better.
No problem towing a 120" f3j ship with this winch. For the battery: it must
be a deep cycle type. get one that as a good warranty on it,
you'll need that! Keep the receipt.
do not use the flimsy marine type connectors, I burned one through the battery
because the
connector was a little bit corroded and heated up. (200A is nothing to fool
around with!).
Use the thickest cables you can get and make them as short as possible.
Answer by Paul
Depends on the application... In general, with NiMH, you can expect
about 50% more duration over high capacity NiCD or 100% over "standard"
NiCD. Higher internal resistance than NiCD. Beware high current apps
unless you are using high capacity NiMH, with penlight sizes (<1500ma)
as current load increases over 8-10a, capacity decreases sharply. Can
be recharged fewer times than NiCD. They do not like to be fast
charged.
1) NiMH works well for receivers, transmitters and other low current
draw (5-10 amp) applications.
2) Penlight-type (<1500ma) NiMH works well for eFlight in low current
draw (5-10 amps) Speed 400 type appliations, but only if your
interested in low-throttle long duration flights. They work well in
slow flyers like the Wingo.
3) High capacity NiCD (i.e. AE type cells) also works well for lower
power Speed 400 stuff, offering more power than NiMH over a reduced
burn time... and more duration than fast chrge NiCD. They can take
some fast charging, but it isn't recommended.
4) Larger capacity NiMH (>1500ma has made great strides in delivering
more power, but are still best suited for duration flights on larger
ePlanes. Can be recharged fewer times than NiCD.
5) Fast charge NiCD (i.e. AR type cells) offer more power output
(lowest internal resistance) than any of the other cell types. Widely
used for high performance applications, pylon racing, F5B, aerobatics
and sport flying. Heaviest batteries of the bunch, but they can put
out 20-30+ amps and are very rugged. Designed to be fast charged, so
turn-around time is shorter.
Answer by Brian Findlay
I noticed that this phenomenon always happens at the same relative spot
(ie geometry), so I am positive that it is the orientation of the reciever
antenna. Since the antenna is completely buried in the wing, it forms a
'plane'. When the plane is edge on to the dipole of the transmitter
antenna, it sometimes blips. I suspect that if the reciever wire was
trailing, this wouldnt' be a problem. (course, tangling with the prop WOULD
be a problem!).
Answer by Gerrit Hiddink
A thermal is a bubble of rising air. Thermals are created by earth surfaces
(parking lots, roads, forests) that are warmer than surrounding surfaces,
for example because they're heated by the sun. These bubbles (or columns if
they're continuously fed) of warmer air
rise upwards, just like a balloon does. If your plane happens to be inside
that bubble, then it will also rise, or descend less rapidly.
Answer by Dan
Inside a thermal, you fly circles or figure 8's.
It depends on the size of the thermal which is basicly a
column of rising warm air.
Answer by Dan
I cross back and forth over the field to find a thermal, looking for that warm
spot. A good thermal can make the plane seem like its riding up in an
elevator sometimes. Lift and altitude climb can be VERY noticable!
There are a lot of tricks (most of which I dont know) but mostly I just fly
back and forth in straight lines till I notice the plane seems to be pushed
aside or deflected. Thats a thermal. I then turn the plane back towards that
deflection. Usually, you can see the plane climb once you are in the thermal,
sometimes quite a lot! Then its just a matter of sticking around that spot of
sky feeling your way around to gauge the size of the thermal.Lazy circles or
figure 8's.
Answer by Jeff Reid
No you cannot, a glider or planes only reaction to a steady wind, is that
it's ground speed will vary while it's air speed remains basically constant
(if the plane/glider is flying level...), depending on the direction of
the glider.
This may be an optical illusion, any time you fly an RC-model away from you,
it can appear to be losing altitude, and when it's flying towards you, it
can appear to be gaining altitude, due to the visual angle above the
horizon that you're viewing the model with.
With an eletric glider, when viewed from the ground, a climb will appear to
be steeper when it's flying into a headwind as opposed to a tail wind.
Relative to it's airspeed, the climb is the same.
Answer by Joe Wurts
The energy increase in dynamic soaring is due to flying into a airmass that
gives you a change in airspeed "free" of charge.
One of the slopes that I have been flying at has a very pronounced "razor
back" to it (Parker Mountain near Acton CA). What is really neat about it is
that the air behind the hill is completely separated. That is, it can be
blowing 25 mph on the face, and behind the hill, it is almost calm and
sometimes even blowing softly in the opposite direction. It turns out that
this is an absolutely perfect set-up for dynamic soaring. All you have to do
is fly straight down-wind over the hill into the calm air and turn around. If
you want, when you come back over the upwind face, turn around and repeat.
With each turn, you get an amazing boost in the energy of the glider. The
first time I really played with this was with my Floyd, and on the second
go-around I fluttered the wings. The plane will take an extended vertical
dive without any possibility of flutter, so I was able to get it to above the
terminal velocity of the glider in horizontal flight!!!
One thing that is especially wild is when the wind dies down a bit, and you
can just stay up in the normal lift in minimum sink mode. Start doing the
orbiting for the dynamic soaring and you can get up to about three times the
speed that you can when you just fly in the normal slope lift. Wild stuff.
If your slope has separated air behind the hill, and you do not mind
occasionally crashing while you learn a new trick, give this a try. Caution,
I'd recommend trying this maneuver out sometime when you have the hill to
yourself. It takes a little getting used to... And a hint, the lower you go
on the downwind side, the better off you are (more delta-vee typically).
Lets go through an example
here. Lets assume a 25 mph wind on a slope, with the backside completely calm
(I've flown at slopes where the wind on the backside is blowing towards the
top at 1/2-2/3 of windspeed, but we will use the worse case above). I turn
downwind with 25mph airspeed, and with the windspeed, I get a 50 mph
groundspeed. I then enter the calm air, and with the 50 mph gorundspeed, I
now have a 50 mph airspeed as well. I turn around, and fly into the active
wind on top/in front of the hill with this 50 mph groundspeed and the 25 mph
wind speed I now have 75 mph airspeed. Without drag/turning losses, each turn
adds 25 mph to the airspeed! You may also want to look here:
http://ourworld.compuserve.com/homepages/dlstone/dsoar.htm
Answer by Pé Reivers
3D flight is what it says, three-dimensional. Of course all rc flight is
three-dimensional, but 3D is extreme, like the cobra that Russian jet
fighters exhibit. It is even more extreme than fun flight, because very
large control inputs makes the plane go far beyond the flight envelope. That
creates totally new flight figures: 3D
Answer by Howard Lute
I use the Ultra Bright LEDs avail from Radio Shack...they are VERY bright
and are easily aimed across the wing under side which makes it very easy
to spot and fly the plane in pitch black nite.
Answer by Alan T.
Check this URL: http://www.aerofoam.com/nopspage.htm
Answer by Craig
Here's another lighting system that is much cheaper and works just as
good as the night-ops: http://www.rcneon.com/
Answer by Red S.
Minimum charge rate recommended for fully charging a pack is C/20, but this
would take 32 hours or so.
Have a look at Red's R/C Battery Clinic at
http://personal.lig.bellsouth.net/~redscho
Answer by Gerrit Hiddink
You can find a Battery FAQ at http://www.repairfaq.org/ELE/F_NiCd_Battery.html or at
http://user.aol.com/ralph234/cb-page/f_nicd_b.htm
Answer by CDance7412
Glow plugs usually require 1.2 to 1.5 Volts of DC power. Your local hobby shop
or Tower Hobbies can provide you with a lock-on adapter that has a built in
battery or, If you have one, plugs into pour power panel.
Answer by Mike
D size alkaline 'batteries' have really improved over the last 10
years. I usually have a 4000mah NiCd D cell for a glow battery but forgot to
charge it for my first flight last Spring so I grabbed a Duracell D cell from a
flashlight. I used it all summer, (not a lot really in my case, only maybe 30
to 40 engine starts).
It's long way from the days of the Union Carbide 1.5 tennis ball can size
zinc-carbon cells with the screw terminals on top.
Answer by J.D.
For Cox engines, I always used to use Cox Glo Fuel. From what
I understand, these small engines
up thru the .15 like high nitro, at least 15%, preferably 20%.
Answer by Patricio W. Concha Erilkin
Here, due to the expensive of the the fuel, most guys with .049's and .061's
use just 5% nitro fuel (mostly powermaster) ... and no problems at all !
Answer by Pé Reivers
Supertigre, Webra, Moki, MVVS and many others advocate
use of nitro. They also advocate to adjust compression ratios when large
volumes of nitro are used.
Answer by Paul Mcintosh
I have been running all manner of engines for many (35+) years on all
types of fuel. No-nitro fuel, while cheaper, does NOT run as well in
the majority of engines made today. I usually run 5-10% nitro in all my
2-c engines and 20-50% in my 4-c engines. I keep hearing about Laser
engines and how great they are on no nitro. I don't see anyone telling
me what size props they turn at what RPM. And, they cost up to 3 times
as much as other 4-c engines available here
Answer by Mike
I never saw the TeeDee throttle version but I have a Cox .049 with an
exhaust throttle that worked fairly well. It is basicaly a ring around the
lower part of the cylinder that is rotated to partially cover up the exhaust
ports and limit the flow. It also had a muffler feature of sorts that really
didn't do much. I think this method might work on
a TeeDee too. It would be a simple thing to make and try.
Answer by ronenj@hotmail.com
First attach the fuel line to the engine, shut the venturi with your
finger and turn the prop a few times just until fuel fills the hose.
Then, put 2-3 drops of fuel through the outlet holes in the cylinder,
turn the prop twice, attach the glow plug and start the little one.
Be patience, it may take a while till you get it...
Answer by Gerrit Hiddink
This seems to be normal for some engine types, such as the Zenoah G23
and G62. It seems to be a by-product of normal break-in, and is
nothing to worry about. It should taper off after about 2 or 3 hours
runtime.
Answer by Pé Reivers
Route the fuel line behind, and against the cylinder. This provides
sufficient heat for stable cold weather operation. Your trick stops working,
when the plane is fuelled up and has cooled down by propeller wash and
flight wind, leaving you with not quite correct needle settings. Denser
winter air containing next to zero water vapour means richer settings to
provide the fuel to match the oxygen content and restore fuel to air
ratio's.
Answer by Ray S.
If you're interested in increasing power with a 2-stroke, there are
several areas which pay off. First, increase the base compression
(the compression ratio within the crankcase) as much as you can.
Second, the exhaust port area does NOT need to be over 65% of the
inlet port area, and make the inlet port area as much as possible.
Third, our present design 2-strokes pass over 50% of the incoming
fuel/air misture straight out the exhaust without burning it. A
baffle needs to be added to the piston to prevent some of the inlet
gas from going straight out the exhaust. Make sure you use "squish"
area in the combustion chamber to retart detonation.
Yes, you can do it but it will take time. No easy task.
Answer by Dr1Driver
A piston/cylinder fit is never perfect. You'll always have some escaping
air/fuel, especially if the crank is turned slowly. You didn't say if the
engine is ABC or ringed, but an ABC engine only fits well at operating
temperature, and may actually be tight when cold. A ringed piston/cylinder
will sometimes leak badly at room temperature, but will tighten up when hot.
If it still runs well, don't worry about it.
Answer by Steve Lewin
The 5th channel never will work if you are using the joystick port.
It's only got 4 analogue channels. If you are trying to use the
printer port like the real interface does then you will need the
software wich reads it. The basic program only reads the joystick
port.
Answer by Gerrit Hiddink
Download Ron's free simulator at http://www.pivot.net/~acarr/ron/ron.htm.
Answer by Pete Christensen
http://www.rcmicroflight.com
Answer by Murray Lane
For U. S. residents, an organization well worth joining is the Academy of Model Aeronautics (AMA). They are the modelers' main
voice where it matters---they liaison with the FCC, the FAA and Congress. It is an affiliate of the National Aeronautic Association
(NAA) and is the US aeromodeling representative of the Federation Aeronautique Internationale (FAI). Membership in the AMA
also gets you $1,000,000 of liability insurance, without which most fields will not allow you to fly. You also need to be an AMA
member to participate in contests. Besides, you also get a magazine, `Model Aviation' which is rather good in itself, and it keeps
you informed about the state of the hobby. Membership is $42 per year.
Answer by Gerrit Hiddink
In the Netherlands, there's the Koninklijke Vereniging voor the Luchtvaart (KNVvL). It works about the same as
the AMA in the United States: you get a liability insurance, a magazine, and they represent the airplane modellers
on a national level. Many clubs only allow you to fly at their airfield if you are a KNVvL member, afdeling Modelbouw.
Answer by British Model Flying Association
The term HOLD refers to a scenario whereby the servos HOLD the
position they were in just before some kind of interference arrived.
The term PRESET refers to the moving of the servos into
pre-programmed positions which were defined by the operator before flying, and
FAILSAFE is a generic term to cover both.
If you use a typical Computerised Transmitter, or have members
in your club who do, you should be aware of the following basic findings.
Almost all sets give an automatic PRESET/HOLD feature
within the program
as soon as PCM is selected. This failsafe becomes operational if interference
occurs at the receiver of the model or the transmitter signal is lost. Control
returns to the pilot when the interference ceases. If interference does not
cease, the pilot will not regain control.
The failsafe software cannot be totally inhibited. It will either hold all (HOLD)
or go to positions pre-programmed by the pilot (PRESET). Some sets allow a
combination of this feature. i.e. some channels will go to a PRESET position
and some controls will HOLD at their last position.
The default setting if nothing is programmed is to HOLD at last input position,
including throttle. This will become operational after a pre-determined interval
set by the pilot (1.0 seconds, 0.5 seconds or 0.25 seconds) or after a default
interval if nothing is programmed. The interval is the length of time it takes,
starting the moment interference occurs, until the servos assume their pre-set
positions. [...]
We recommend that particular care is taken by all individuals when operating on PCM or
when swapping from PPM to PCM to ensure that the PRESET/HOLD feature is correctly
programmed with throttle to tick-over (stopped in the case of electric power).
Answer by Chollie
This sets off alarms. AMA (American Modeler's Association) rules do not allow
over-flying people on purpose. (Check your local law for the situation in your
country, GH)
Dropping anything at all, however well intentioned or however benign,
onto or among those people opens wide doors to potential liabilities and
lawsuits.
Answer by James G. Branaum
I have seen it done with some care. Since there is a prohibition against
overflying spectators, you will have to learn how to 'drop' the candy while
in a moderate G loaded turn. That will 'throw' the candy. Your task,
should you choose to accept the challenge, is to determine how to control
where the load lands....
Answer by Gerrit Hiddink
You can replace the antenna by yourself, if you know how to use
a soldering iron. If not, you may get used to it by practicing on
an old piece of circuitboard.
If there's still a piece of wire sticking out of your receiver, then
you don't need to replace this piece. It's better not to, because then
you don't have to solder your receiver circuitboard. There might be
a risk of overheating if you're unexperienced.
Replace the wire with something flexible, with enough strands in it.
But whatever you do, make sure the length is the same as the
original! The length varies with the base frequency of your
transmitter. Always do a range check after repairing!
Answer by Bob Peck
I use a homemade brew that works very well, and is inexpensive. It removes
grease and cleans up without streaks.
1 cup Rubbing Alcohol
3 teaspoons amonia
3 teaspoons liquid dish soap
1/2 gallon water
Answer by James G. Branaum
Look for 'K2R' in the household cleaners isle of your local Albertsons.
Answer by Paul J. Burke
K2R is a very good oil-soaker; used after a fuel tank incident in
fuselages, it does a good job. However,
California has just -expanded- the list of illegal chemicals to keep us safe
from ourselves.. I haven't seen any at Albertson's for close to a year.
Answer by Dr1Driver
K2R can be found in Wal-Mart. Glue will
not stick to oily wood, and the wood will remain weak unless the oil is removed
and the wood soaked with thin CA.
Answer by B C
We had a Lazy Bee that got oil soaked and from advice we used Corn
Starch after using K2R with no results. Applying corn starch to the area
and heating with covering iron the oil was gone!
Answer by Grain
If you can't find K2R then try mixing alcohol and corn starch together.
Heavy on the alcohol, but not to the point of dripping. This will work, but
it will take several applications if it is really bad.
Answer by ratman
I soak the affected area with rubbing alchohol then cover with
a paper towel. then iron the paper towel till dry. repeat till the paper
towel comes clean. will at least get it clean enough for the covering to
stick.
Answer by Al Eastman
Get a bag of plain old kitty litter and bury the fuse for several
days. Oil all gone!
Answer by Dr1Driver
Run standard synthetic/castor if it's ABC, or total synthetic if it's ringed.
Webras take a little longer to completely break in than some others. If it's
ABC, break it in only slightly rich, if ringed, richen it more and take a
little longer.
Answer by Gerrit Hiddink
You should break in an electromotor for about 30 (!) hours on about a
quarter of its voltage, or half an hour on full power under water.
You have to do it under water to make sure it doesn't overheat and to prevent
sparking (else your collector will burn). Some sources
suggest to use destilled water instead of tap water; destilled water is a worse
conductor than tap water so you will get less unwanted chemical reactions due to
the presence of electrical current.
Answer by John Equi
I've been using a 5% mix of ammonia in paint remover (clear jelly) for
years, works good if the stuff is at room temp or slightly warm. The steel
parts can be cleaned in spray oven cleaner, and the piston tops sanded on a
flat with 600 and oil. All other parts can be cleaned with 5x steel wool. I
ultrasonically clean everything 2 or 3 times before reassembly in lacquer
thinner.
Answer by Vance Howard
go to a truck stop. there should be a product made by Eagle One for
cleaning oxidization off of aluminum, forgot the specific name
(it's called "Mother", GH), it comes
in a spray bottle, spray it on, let it sit 10-15 minutes and rinse off
with water. pretty nasty stuff, do it outside and wear rubber gloves.
works great on truckers big aluminum wheels, should work on the engine.
remove any plastic parts and gaskets first though.
Answer by Miles
Go and get an old crock pot and fill it with antifreeze. Cook the
engine, dissembled, for about 24-48 hours. It should come clean with no
problems. (Do ventilate the area. You can reuse the fluid for
future cleaning activities, but do not use the pot for
food purposes afterwards ;) , GH)
Answer by sport_pilot
You can just let it soak in denatured alchol for a day or so too.
Answer by John Laird
In UK , some of us clean engines with paint and varnish stripper - as used
to take paint off wood etc in home.
Active ingredients are methylene dichloride and methanol - stuff is
hick - paint on and leave for 20/30 mins then clean off with water and
tooth brush.
Not used yet for 4 strokes but suggest ok if kept away from rubber(?) seals
for push rods/carb etc
and off course - block the carb / exhaust .
Answer by misc
If the cover-glue has vanished due to dirt, fuel or cleaners, you can clean the
attachment surfaces with Windex. Apply an adhesive like Covergrip, Stix-it, q
Balsarite (from Coverite) or Balsaloc, allow to dry and seal by heating with an iron.
Balsarite is a paint-on, heat activated glue. It was/is used for attaching Coverite fabric covering
to model surfaces. Pull up your monocoat pieces a little, and jam some
BalsaRite under them using a small brush. It dries in about 15 minutes,
and then take your heating iron and reseal the monocoat down. Clean up
an excess BalsaRite that you've smeared on the plane with some acetone,
and you're all set! Make sure you clean your brush with acetone, or
dope thinner, 'cause BalsaRite will gum it up real good.
