Rc Plane Reciver Amp Draw

Coming in hot on the tail of my last article, I'thou going to keep the momentum of my 'How Do I…' string of articles growing! As I stated in the thirty-45cc commodity, I plan to cover as many different topics as I tin in our hobby! Of course, I don't know everything there is to know nearly the hobby, just I'm going to share that which I do! Hopefully, I tin give some pointers to those just getting into new areas of RC airplanes. This article is going to focus on giant scale aircraft, but I'k going to split this topic into three different manufactures. Why? Well, I'k glad you asked! The reason is this – setting upwards some giant scale aircraft are easier than others. Larger, more complex aircraft take different requirements than smaller planes. And so, before nosotros go into the thick of this, nosotros need to answer one more question…

What is Behemothic Scale?

I went over this in the first commodity, simply I'll go out it hither as well. Behemothic scale is divers by iv simple criteria:

ane) Monoplanes must have a wingspan of at least 80″.

two) Biplanes must have a wingspan of at least 60″.

3) Jets must have a combined width and length of 140″. (wingspan and length of fuselage added together must be at least 140″)

3) If none of the higher up is true, the aeroplane MUST be a true 1/4 scale.

If an airplane does not meet at least i of the iv criteria above, it will well-nigh likely non exist considered giant calibration.

What is This Commodity's Purpose?

The purpose of this article is to help build on the base of my first article. We'll proceed here with 50-70cc airplanes, and the third article will cover 100-120cc aircraft! Now, as much equally I would dearest to keep going, the largest airplane I've had to date is a xxx% scale Stearman biplane. I'g going to stick to what I know….  Hopefully, I've got your involvement piqued – if then, read on!

Building/Assembly Expanse

The get-go thing yous're going to want is a relatively large edifice/assembly surface area. I have a shop in my basement, and I volition admit that information technology's not almost as large as I'd similar, just information technology gets me by. Unfortunately, I am limited to 7 foot ceilings in my basement, so assembling large airplanes can get a little difficult. Many of my larger projects take their final assembly done out in my garage.

My bench is a full 4 feet wide by 8 feet long, and was fabricated by me. The frame is made from 2×4 lumber standing on edge, with a sheet of 3/4″ OSB (chip lath) on top of the 2x4s. A ane/4″ Melamine superlative layer makes for a nice bench summit, especially for all the photo work I exercise. The legs are made of 2×4 lumber besides, and screwed together in an 'Fifty' configuration. I've used this bench for close to 10 years at present, and it'due south still apartment – If I ever need to true upwards the pinnacle, an additional frame member tin be added with two more legs.

In my get-go article I used the Great Planes Avistar 30cc ARF. With a 96″ wingspan, it's longer than the 85″ wingspan of the 50cc 29% CAP 232 from The World Models I'll be using in this article. But, that's the simply part of the Avistar 30cc ARF that is bigger than the CAP 232. So, moving the wings around in my shop was a fiddling bit easier with the CAP, but the fuselage was longer and much heavier. This fabricated maneuvering in a pocket-size space slightly hard, but still manageable.

Assembly/Installation Tips and Tricks

As I said earlier, this article will carry on from the get-go, meaning that yous shouldn't forget about all the things I mentioned in the first article! A lot of what you'll need for the 50-70cc shipping volition be very shut to what nosotros covered in the thirty-45cc article. Things that are different, and things that I feel are important will be covered here.

For some of you, this type of servo setup will be Two firsts – start time using a circular servo wheel (you lot know the 1 that'southward included with every servo you purchase, merely it ends up in a miscellaneous box in your shop), and the get-go fourth dimension using a servo arm extension that is attached to said servo wheel. For the World Models CAP 232, these arm extensions are attached to the wheel using 4 small machine screws and locking nuts. In society to correctly install this extension, the servo must be kickoff centered using the radio system or a powered servo tester. With the servo centered, the arm extension is set up in place and the iv holes are marked and drilled. The automobile screws and locking basics are then installed to secure the arm extension. It is also important to note that, even though these are locking nuts, I still added a drop of the blue thread locking chemical compound to each machine screw before tightening the nut in place.

For nearly of us, information technology's just a habit to allow space betwixt the servo and it's mounting hatch, only I'm going to mention it here. If you lot've only run electrical powered airplanes prior to making the bound to giant calibration, y'all might non be familiar with this step. Information technology is imperative to continue a gap between the servo and its hatch. This minimizes the amount of vibration transferred from the airframe/engine to the servo. Some people utilise an sometime card, such as a hotel primal (go along these as frequently as you tin can – they come up in handy for Then MANY THINGS!), only I prefer a 1/64″ piece of aircraft plywood. It has been cut to the width of a standard servo, and is approximately twice as long as the servo is tall. Equally you can see, I have also written 'Save for servo spacer' on information technology, so it doesn't accidentally become thrown out when I'm cleaning off the piece of work bench.

The servo is attached to the hatch with four servo screws, once again, I really like the DuBro Socket Head Servo Mounting Screws. The socket caput makes them much easier to get installed (and removed if necessary) than a traditional Philips head screw.

One other thing yous'll find on this servo arm extension it that at that place is only one pushrod connection hole – and it has a ball bearing! The World Models does this with a lot of their large scale aircraft. the clevises utilise a pocket-size car screw and locking nut as the pin in the clevis. This makes for a secure connexion that has very little friction!

Servo Option

When y'all get to the indicate that yous're wanting to build a kit or assemble an ARF in the 50-70cc size, servo choice becomes important. While I mentioned the high torque requirements in the xxx-45cc article, choosing the right servos is even More of import now! Hither'due south my number one recommendation for purchasing the right servo for the job at hand – DO YOUR RESEARCH! You're going to want to spend some time finding the correct servo for your giant scale shipping. Depending on the airplane, you're going to exist looking for different servos. Besides the torque value, you'll desire to look at servo operating speed, operating Voltage, digital or analog performance, brand, receiver type, and of class, toll. All of these factors will counterbalance in on which servo is right for you. Let'due south break these downwards a flake…

1. Torque – The torque value (how much force the servo can apply to the control surface) is probably the most important factor in selecting a servo for your giant scale project. This volition vary depending on the project – shipping with large command surfaces, similar 3the CAP 232 used for this article, volition demand servos with a higher torque value than a giant scale trainer or general sport aeroplane. Both airplanes will crave servos with more torque than your standard .40-.lx sized airplane, but the CAP 232 will demand more than the sport plane. For 50-70cc shipping, you'll probably want to look at servos with a minimum torque of 125 oz./in.
2. Operating Speed – Similar the torque value, operting speed volition vary by aircraft type – an airplane designed to perform 3D aerobatics will need a servo that operates faster than a servo for a warbird or a sport airplane. Typical servo speeds are in the range of .eighteen-.23 seconds for a lx° rotation of the servo output shaft, while a high speed servo tin can rotate that same distance in .xiii -.17 seconds. Some servos are fifty-fifty faster! A large warbird or sport aeroplane doesn't need a servo that moves that quickly.
3. Operating Voltage – This topic is becoming less of a factor, equally many new servos have a larger operating Voltage range. Some servos still take an operating range of just 4.viii-6.0 Volts, and so you'll desire to cull the servo based on the type of receiver battery you want to employ. If you're going to utilize a 4-v prison cell NiMh battery to ability your receiver and servos, then a 4.eight-6.0 Volt servo will work for you. Nevertheless, with newer receivers able to handle an input of four.8-viii.4 Volts, LiPo and LiFe batteries have become a very popular option for flight batteries! But, just because your receiver can handle the actress Voltage doesn't men the servo tin, then choose accordingly. Servos that tin handle the higher inputs will be labeled with 'High Voltage' or 'HV'.
4. Analog or Digital Servos and Receiver selection – For the most function, the simply reason I'm mentioning this is because there are receivers bachelor that volition only work with digital servos. I apply a lot of Hitec equipment, and they accept receivers that will ONLY work with digital servos. Make sure your servos are compatible with your receiver!
5. Brand and Price – Lastly, we have brand and toll. These will get hand in manus, as many name make servos will cost more the lesser known brands. Now, the name on the servo doesn't automatically hateful information technology's going to be a better servo – Not all of us tin can beget to spend $100 plus dollars per servo, but this is why you lot need to do your research!

Always, always, always harden spiral holes in wood with thin CA – this is very important when working with Internal Combustion engines, and even more so with large airplanes!  One time the CA has cured, the servo hatch can exist installed. As you can see, the command horn on the CAP 232 looks unlike than what nosotros saw on the Avistar 30cc ARF. The World Models uses a long motorcar screw with plates and a locking nut. The 'horn' is a plastic tab that is turned on to the machine screw, and has a ball bearing in information technology for smooth, bind free operation. The last photograph shows the completed aileron setup, with the servo hatch, pushrod, and control horn all connected as one unit.g It's a stout, slop complimentary configuration that works very well! If y'all await closely at the last photo, you can run across that he black section of the pushrod looks rough – this is because the fiberglass shaft over the threaded pushrod was splitting at the ends. I wrapped the fiberglass tightly with nylon thread, and then soaked the thread with medium CA. This made for a very tough pushrod!

The rudder servo arm extension is attached to a servo cycle like the ailerons, and likewise has the ball bearings. The rudder's control horn is similar to the aileron setup, except that information technology is a pull-pull pattern. Some of you may not have ever used a pull-pull rudder system, so I'll break information technology down a bit. Instead of a solid pushrod, a pair of wires are used to pull the control horn in each direction. A command horn and cable are used on each side of the rudder to move the control surface. The wires (in this case, they are a nylon coated braided stainless steel wire) is looped through an eyebolt connected to a clevis. There's usually just a few inches of extra wire included with the airframe, so you'll want to make the first connection as shut to the end as possible.

The clevises are attached to the rudder (again, one on each side) and pulled fairly tightly through the fuselage. The other cease is then attached to the servo arm in the same style every bit the rudder. In this detail airplane, the pull-pull wires cross – so the left side rudder connection is on the right side of the servo, and the correct side rudder connectedness is on the left side of the servo. The do good of this is seen when the wires exit the fuselage at the tail end – they come out at an angle that won't continuously rub on the fuselage and so there'southward less binding.

The engine box is non installed in this CAP 232 ARF – A smaller shipping box can be used this way, and it's pretty easy to install. There's a couple of formers that are glued in place on the top that assist to 'central' the engine box to the fuselage. At present, when I say 'mucilage', I hateful epoxy. The engine box will become epoxied in place, and you lot will utilize epoxy to every function of the box that makes contact with the fuselage. YOU Practice Not Desire THIS TO Interruption LOOSE FROM THE FUSELAGE!!!

Nearly every airframe in this size is going to have at least i servo operating each command surface. For the CAP 232, each half of the elevator is controlled by its ain Hitec HS-5645MG servo. These are loftier torque, digital, metal geared servos, but are even so reasonably priced! Each servo is mounted to a hatch and has the same slop free setup as the aileron pushrods. This is a slap-up way to set upward behemothic calibration shipping! Likewise, this might be your first model with tail mounted servos – you'll want to make certain you take servo wire extensions on paw that are long enough (and are heavy-duty wire) to accomplish from the tail of the plane to the receiver location.

With a 50-70cc aircraft, you're going to be using some pretty hefty landing gear. The good news is that it'due south fastened in a very familiar mode – with screws! The CAP 232 uses car screws and blind nuts installed inside the fuselage on a landing gear mounting plate. A expert sized drop of blueish thread locking compound was applied to each auto screw equally information technology was installed. The axles were then installed and apply a large diameter threaded commodities and locking nut. That bolt has a hole drilled through the center, and the axle is welded to the bolt. One extra precaution I take with big models is to grind a flat spot in the bottom side of the beam in the approximate locations of the set screws. this flat spot gives the set screw a better surface on which to 'bite'. The bicycle has a bike collar on each side – again the set spiral has a drib of thread locking compound on it.

The CAP 232 has a pretty cool sprung tail wheel assembly, which dampens the corporeality of shock on the tail while the plane is on the ground. The steerable tail wheel is fastened to the rudder by a pair of springs and a 'tiller' arm which is screwed to the bottom of the rudder.

The CAP's fuel tank was assembled and installed per the manual – in that location were some actually nice spring clips included with fuel tank, and a short department of neoprene fuel tubing for inside the tank. I added a second fuel line and clunk to make filling the tank easier. I used the 'Make full It' Fuel System  and large Tygon Fuel Tubing  from DuBro. A piece of 1/4″ Protective Foam Rubber sits under the fuel tank, which is secured to the tank tray with a pair of heavy-duty Zip Ties. The Tygon Fuel Tubing is secured to the fuel tank aluminum and brass tubes with twisted mechanics wire – I wrapped the wire twice around the fuel tubing and and so twist it tightly to secure the tubing. An engine that runs reliably needs a fuel system that is prepare correctly!

Of course, engine selection is key also. My Globe Models CAP 232 has had two different engines installed. I have used a DLE 55 and the RCGF 70cc Twin cylinder V2. Both are great choices for the CAP 232, as the CAP has a wide cowl – even the twin is near 100% concealed inside the cowl. Simply, beyond just size, reliability is of import. There are several skilful engine companies making engines in this size range – RCGF, DLE, and DA to proper noun a few two-stroke companies. There are also some iv-stroke engines available in the 50cc range as well, but they don't come cheap…  Most engines will have a unique mounting blueprint, and the overall length of the engine will vary besides – the length is important to note when trying to match an engine to an airframe. Engine weight can also factor into your engine choice – a short-nosed airplane like the Sopwith Pup will require more nose weight than an plane like the Pilatus PC-6 Porter.

The engine length was perfect, then mounting the DLE 55 with its included standoffs was easy. The Bisson Custom Muffler was a tight fit, simply it merely cleared the firewall! Bisson has a big pick of set up to use aftermarket mufflers, but can also custom make about whatsoever design to fit your particular need. I have another muffler for the DLE 55 that was custom made to fit between the engine and the firewall of a different 50cc plane. Bank check them out when you need a muffler! In addition to the muffler's newspaper gasket, I added some high temp RTV frazzle gasket maker. The red stuff is great, and a tube will last for a long fourth dimension!

Throttle servo placement tin can exist difficult, depending on the plane and the engine's carburetor placement. The CAP 232 has a large expanse to mount the servo, so placement was like shooting fish in a barrel. The receiver and battery were also easy to install considering there's a lot of room within the CAP'southward fuselage. Be sure to follow your receiver'southward installation instructions for antenna placement for optimum performance of your radio system. The CAP 232 as well has plenty of room below the firewall to mount the ignition organization. I added an optical kill switch, so I can shut off the engine ignition from my transmitter. There'due south a few different manufacturers of optical kill switches, and they're reasonably priced for the safe they add. Pick one upwards for your next airplane, and I'm sure you'll like information technology! Because I cut the exhaust tubes short for a dissimilar projection, I had to extend them for the CAP. I picked up a short length of high temp silicone tubing on Amazon.com for a few bucks. A pair of modest hose clamps keeps the tubing in place.

Installing the RCGF 70cc twin was nigh as easy as the DLE 55, but required adding small spacers to go the propeller hub to the correct position. I also had to move the throttle servo and engine ignition box, and a DuBro 4-40 steel pushrod and brawl link were used to connect the throttle to its servo. Over all, the engine swap was pretty easy, and I did find a slight improvement in operation with the 70cc engine.

Propeller selection, while a personal selection, is of import. You'll desire to use a high quality prop, of course. I really similar wood propellers for a couple of reasons. Commencement is safety. In the event of a prop strike (against an immovable object) the propeller volition break rather than damage the engine. In the event of a prop strike against me, the woods prop will do less damage compared to a carbon fiber prop. At that place are Nylon props available as well, just the edges can be as abrupt as a knife's blade! My propeller of choice is the Falcon Beechwood prop. Falcon props are bachelor at justmodelprops.com.

Flight Your New Model

By the time you're gear up to gather and fly a behemothic scale shipping, I'm going to assume that you're able to fly an plane. With that said, I desire to mention things that volition exist focused on larger airplanes. The first is in regards to your flying site. Larger aircraft require more room! From runway length to air infinite, you're going to demand more room in most cases. My flying field has a 135′ nylon mat runway, which is too brusque for most giant calibration aircraft, so I use the grass across the runway for take offs and landings. The one problem I have at my local field is that the total length of the mowed field is only 400 anxiety, with alpine grass and trees on each end. We also accept a air current generator located 660 feet off the southeast corner of the rail. This makes our landing pattern from the East a little difficult, but we manage to get by… Thankfully, there is another flight field located most 35 miles to the northeast of where I live. This field has a 700′ grass strip, which is more than sufficient for every airplane I've always owned!

Another thing to remember about is rubber – large airplanes swing large propellers! My recommendation is to never fly lone. If you were to have an accident at the field, who would be there to help? Though I've never had or personally witnessed a major blow at the field, I've seen many photos of problems that would have been a lot worse if the modeler had been at the field alone. Utilise the buddy organisation!

OK, so now on to flying. Flying a giant calibration model is a lot like flying a smaller model, only bigger. Bigger usually flies meliorate – larger planes are less affected by air current, so in that location's more days available for flying. With that said, pick a calm twenty-four hour period for the maiden flight. It's much easier to focus on adjusting the trim on a plane that isn't existence bumped effectually by wind. Now, here's some other place it's adept to have a buddy at the field. They tin accomplish over and help you by adjusting the trims on your transmitter while yous proceed to fly the plane. Information technology's a footling awkward at first, but it can be a HUGE assistance if your model is way out of trim!

One time your model is trimmed and flying straight and level, information technology'southward time to commencement finding out the limits of your new airplane. Outset your initial tests at an altitude of '3 mistakes' high. Of course, 'iii mistakes' loftier will vary by the plane, so just exist sure to requite yourself some room. You'll want to check the high and low speed flight characteristics to see how your model reacts. Determining a stall speed will be imperative for polish landings and knowing how slowly the aeroplane will wing and not fall out of the sky. High speed characteristics are important to know to avoid problems. gradually increasing the speed of your plane while flying direct and level volition show you how the plane reacts at unlike speeds. once you lot've striking full throttle, and the airplane is withal flight well, y'all're in pretty expert shape. The only thing left is loftier speed flying in a dive, but depending on the plane that may get destructive – save that for another mean solar day…

At this signal, it'south a good idea to land your new plane and give it a good inspection. You lot'll desire to check over the entire aeroplane and make sure that all the nuts and bolts are tight, and also bank check the control surface hinges and edges of the covering. Pay close attention to propeller bolts, pushrod clevises and pushrods. The airframe should be in the same status as it was when you finished edifice/assembly. If there is annihilation that needs attending, Practise Non wing the plane again until the problems have been stock-still! when you're satisfied that your new behemothic scale aircraft is still flight worthy, go accept fun!

Summary

I won't begin to pretend that I know everything there is to know most behemothic scale aircraft, but I hope what I know will assist others. If there's anything that you'd similar to add, please feel free to leave a comment below. Thanks for reading my article, and stay tuned for function three – 100-120cc aircraft!

That's all for now – from my shop to yours, Happy Landings! -GB

Contact Data

The World Models – theworldmodels.com

Airborne Models – airborne-models.com

RCGF – rcgfusa.com

Hitec – hitecrcd.com

Zap Adhesives – franktiano.com

DuBro – dubro.com

Falcon Propellers – justmodelprops.com

Bisson Custom Mufflers – bissonmufflers.com

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Source: https://www.rcuniverse.com/articles/editorial/how-do-i-giant-scale-setup-50-70cc/