Complete idiots guide to the E-Sky Honey Bee King V2
By Richard Chase
Preface:
Are you ready to learn to fly an RC helicopter such as the HBK2? If you are like hundreds of others, the experience will be a quite frustrating and miserable with a few brief glimpses of exhilaration/terror. There is nothing quite as disappointing as the quashed excitement of promptly damaging this toy/machine that you waited with great patience to arrive. So with that preface, if you have received one of these great toy/machines, read on at your own peril!
Like any good new heli owner you should have promptly read the entire owners manual right? Oh bugger, the manual is half in Chinese! And there are seriously about a thousand things missing that you should know about flying a heli. Manual, shmanual, lets just give it a go you might think. Disaster probably ensues in a timely manner from this scenario.
Let me take a page out of my own experiences and incriminate myself with an example of what not to do. I should have known better, but I took the HBK2 out of the box, put the batteries in the transmitter (Tx). Set it on a small table, installed the battery, and plugged it in. Twitch, twitch, vroom, it just takes of and flies right into me, whack in the jaw, it falls to the ground and stops moving. I hesitantly go to it and unplug the battery before anything else happens. Then I notice the blood dripping down my neck. I had a nice little slice in my chin from the blade. Wow, what the heli happened? I think you might call it a close encounter of the heli kind.
First law of RC Heli: An rc heli is a dangerous machine! This is not a test! Here is a picture and video of some kid that got hit in the leg by a heli. Not a joke!
http://www.youtube.com/watch?v=NsgtdsdAfWk
Rule number 1) Always maintain the utmost concern for safety in this sport.
Rule number 2) NEVER plug in the battery without the transmitter on first or the heli will behave like a poltergeist! Corollary “ unplug the battery before turning the transmitter off.
Rule number 3) Never forget rules 1 and 2.
I was very lucky to have just been only slightly injured. Yes there have been deaths! Some bloke flying in a schoolyard in Korea supposedly had a transmitter malfunction and lost control during flight and it flew into a bunch of school kids resulting in a death. So, do not take safety lightly. Do not let anyone stand close to you or the heli when practicing. Do not fly near crowds of people. Do not step in a hole while flying. Do not even bump into anything while flying. Do not even stand near anything that might trip you or hinder you from getting out of the way if the heli comes straight at you on accident. I could list a bunch of nasty accidents I have read about online that have happened
OK, you still want to continue? There is really a lot to learn. I am still a relatively new pilot, so a lot of what I have learned comes from what others have taught me by their posts online. So, my first piece of advice is to familiarize your self with several different rc helicopter forums and guides to flying rc helicopters.
The Heliguy main site has some instructional information that is good; the forums have some great sticky how-to posts also.
RC Universe has a great forum and a very worthwhile instructional site at:
http://www.rcuniverse.com/university/
Some quotes:
- Buy a good helicopter book. I recommend the “Safe and Easy Helicopter Flying” by Bob Motazedi. Bob’s book is excerpted on this site. Read the book!!!
- Take your time! The goal is NOT to fly. The goal is to NOT crash.
I really do not want to copy all the information other sites have, so I will whenever possible post links to other sites.
What I would like to do is share what I found to be the most important stuff to me if I were to teach a total newcomer about helis.
Chapter 1 Motor Break-In
The first thing a new owner of a HBK2 should do is break in their brushed motor. Failure to do this will result in motor failure or severely reduced flight time after only a few flights. After about 10 flights my heli only had enough power to hover for about 3 minutes. If you follow the initial break-in method used by many experienced rc fans, your motor will have a much better start than mine did. You should immediately order a brushless motor such as the Esky 3900kV because the stock motor really is not properly sized for this duty and will burn out soon no matter what you do. While awaiting your brushless motor, you can try this.
Steps:
- Put your Lipo battery on the charger. Might as well charge it up while we wait for the motor to finish the break-in. You don’t want to use the Lipo to break in the motor because we are going to let the batteries for this job run completely dry, and you don’t ever want to do that to a Lipo or it will be done for.
- Disconnect the motor.
- Take the landing gear off the heli.
- Take out the screws holding the motor in.
- Find a 4.5 volt power source such as 3AA batteries (rechargeable desired so you can recharge them after). Tape them together or install them in a spare battery tray, or hijack a battery tray from some device you are not using at the moment, such as another toy transmitter.
- Solder two wires to a couple of sewing pins, or some alligator clips or some way that you can connect to the motor terminals.
- Connect the other ends of the wires to the ends of the battery array.
- Add a drop of Tri-Flow or 3-in-1 oil to the top and bottom motor bearings.
- Stick the pin from the end of the battery array into the red wire going to the motor.
- Stick the pin from the - end of the battery array into the black wire going to the motor.
- Let the motor run until the batteries die out (~1 hour or so).
- Take the pins out of the motor wires.
- Install the motor back into the heli leaving just a little gap between the pinion and the main gear about the width of a piece of paper. Some people actually use a piece of paper, but I felt strange doing that so I just estimate. I think it should be ~0.25mm gap or so. Make sure you put some thread locking compound on the threads, you don’t want the motor to ever come loose, and it will due to vibration eventually if you don’t use thread locking compound. I use the blue Permatex.
- Install the landing gear back on.
- Connect the motor back to the ESC.
Why do this? Well, you can search for information about rc brushed motor break in and find all about it if you want. Basically, the brushes are initially rectangular hunks of carbon I am told. Running them with no load at 1/3 to 1/2 the nominal voltage rounds them out to fit the commutator and to smooth out any pits or bumps. This lowers the resistance between the brush and the commutator so it runs with lower current per volt applied. Now when you power up the heli with a load and higher voltage, you will use lower current then with no break-in, which will be more efficient and lower the amount of arcing between the brushes and the commutator. End result the motor lasts a bunch longer before wearing out the commutator and/or brushes.
Chapter 2
Battery Maintenance
Lipo batteries should never be run down below ~2.5 volts per cell, and have a max charge of ~4 volts per cell. The HBK2 comes with a 3 cell battery, so normal operating voltage varies between 7.5 volts to 12 volts. Rule of thumb is, when you notice a change in the sound of the motor for a given throttle setting it is time to power down. If you follow this rule your battery will last a fairly long time. ~300 flights per battery is common.
The stock charger is not that great. Just look at it! It a very wimpy little piece of circuitry. When I first got the King V2 my battery charger was toast. I called for a replacement and they sent me another ac adapter instead. Meanwhile I read a bunch about chargers and had also ordered a Cellpro 4s from FMA Direct. I love this charger, it tells me what the voltage is for each of the cells, automatically adjusts the charge rate over the course of charging the battery for the best rate. Balances the voltage in the cells after reaches 99% capacity in one of them so that each cell ends up with a perfect charge. It will also adjust the charge current based on the ambient temperature and/or the temperature of the battery! Apparently there is a little circuit board in the battery wraps that can monitor the internal temperature of the battery and the Cellpro charger can detect it. This internal circuit is also what makes the battery not chargeable if any cell voltage drops below 2.5 volts, the Cellpro can actually reset the circuit so that is can recover cells that have been over discharged if they have at least 0.5 volts left in them. Oh, this is my favorite; it beeps about 16 times when the battery is totally ready to go. I always get excited when it starts beeping because I know I can go fly if I want to.
If your charger works then that is fine. If you want what I think is the cream of the crop, get a Cellpro 4s They are ~$75 and you need the right adapter for your batter ~$10 total to my door including shipping was ~$95US. A little pricey considering I only spent $175 on the heli delivered, but what the heck.
Chapter 3 Training gear
You will need to use training gear to help prevent damage when first starting out. The heli will easily tip over when getting light on the skids and the training gear will help keep this from happening while you learn to scoot the heli around on the ground and for your initial hovering training.
Chapter 4 Proper Heli Set-up- Getting to know your heli:
4.1 - Tail Blades
The tail blades should be tightened just a bit from stock in my opinion. You don’t want them to be able to flop sideways changing pitch without your command. So tighten them up so that they don’t move unless you flick them gently with your finger.
4.2 - Tail control arms
The tail control slider is the part that has the little links that connect to the tail blades. I noticed these were loose and tightened them up. This was a big mistake; it causes binding and severely restricts the ability to manipulate the tail pitch from the servo. As a mater of fact, a good modification is to use a small drill bit to create a “V” in these holes so the links can move more freely as the slider moves in and out on the tail shaft.
4.3 - Belt tension
The belt should be semi-tight. If you push on it with a dull pencil or your finger it should only move in about 1/16 inch or 1.5 mm. If it is too loose then loosen the 4 screws that hold the tail boom to the heli and pull it out a little, then tighten it back up. You may want to put a small hose clamp or something on the boom where it comes out of the frame so that the boom does not slip back in and therefore loosening the belt without your approval. I use 3mm bolts in the rear two boom clamping locations in the frame.
4.4 - Belt conditioner
You should put a little silicone spray on the outside of the belt once in a while to keep it supple so that is does not get cracks in it. Silicone spray is good, spray some in a cup and let the aerosol evaporate then apply it to the belt with a rag. I have also head of people using lemon pledge.
4.5 Belt pulley
Some users have found that the belt slips off the pulley because of how the heli was put together. I have not had this problem, but many have put a small shim in to correct this problem. Search the Heliguy forum to see a solution to this problem. http://www.heliguy.com/Forum/heres-how-i-stopped-my-belt-from-slipping-t10087.html
4.6 - Tail axel lube
I found that the tail slider was sticking on the axel, so you should put a little drop of Tri-Flow or 3-in-1 oil on it. I actually used a little dab of Vaseline on a Q-tip. That was before I purchased some Tri-Flow. Note about Tri-Flow: the super lubricating part of the Tri-Flow is Teflon and settles out when it sits for a while. You can get a similar product at most bike shops. I saw one in a clear bottle, and found out it takes about a full minute of shaking to get all of the Teflon into emulsion. So shake your Tri-Flow for about a minute before you use it.
4.7 - Tail servo placement
When you spin up the heli it should not rotate on its own without you applying left or right rudder. If it tends to spin, then you need to adjust the positioning of the servo on the tail boom. Move it forwards or back about 1mm at a time until you get no spin. I think you can get an adjustable linkage somewhere, but I have not done this yet. If it spins to the left (counter-clockwise) then move the servo farther from the tail. If it spins right then move the servo closer to the tail.
4.8 - Swashplate leveling
You need to have the swashplate level. You can eyeball it if you want, or you can take the head gear off and use a swashplate leveling device. I followed a user suggestion and found a pen that fit just right on the shaft and a large sewing bobbin that fin just right on the pen. Adjust the linkages to the servos so that the swash is as close to level as you can possible get it. This is really important to any heli so that the controls to work correctly.
4.9 - Blade balancing
Blades must be balanced for Center of Gravity (CG) as well as overall weight. Bob White (finlessbob) has a nice video about how to get it just right. Basically, connect the blades together so the trailing edges face each other. Configure them into a V shape and put a little mark on each blade where they meet. Then disconnect them and roll them (keeping the marks together) on a little rod on a level surface until one of them tips. Put some tape on the tip of one of them until they both tip at the same time. At the place that they just both tip make a mark for the CG. Now connect the blades back together again and see if they balance. I use an Align balancer, it was about $5. If one is lighter then put a piece of tape at exactly the CG until they balance. Now they should have identical CG and weight. If they do not then the heli will vibrate when you try to fly it and it will be unstable. All of Bob’s videos are excellent. I highly recommend watching all of them. Here is a link to Helitown where you can download them. http://www.helitown.com/VedeoInstructionsbyBobWhite.html
To set the blade pitch you have to disconnect the connection to the motor. Then put the heli in idle-up mode and set the throttle at center stick. The pitch of the blades should be set at 0 for center stick, -10 degrees for full down throttle and 10 for full up throttle. Make adjustments to the same linkages to the swash from the blades as you did in blade tracking. Move them both the same amount so the tracking stays correct. If you cannot get 10,0,-10 then at least get the center stick correct.
4.11 - Paddle pitch
The paddles should be at 0 pitch when the swash is perfectly level. Turn on the transmitter, then connect the battery, then check if the swash is level at neutral right stick, then make sure the paddles are at 0 pitch. You have to loosen the grub screw holding the paddles onto the flybar to adjust them.
4.12 - Blade tracking
When the blades spin up each blade should spin in exactly the same track in space as the other. If you look at them from a level view to the blades you can see if one is spinning higher than the other. If so, adjust the link to the swashplate 1 turn at a time until the track the same. The links are designed to attach to the balls in only one orientation. One side of the ball link opening is a little larger than the other and should go on first. If you put a link on in the wrong orientation the lin opening may starch out and increase the looseness of the ball-link connection. You may have to adjust one ½ turn to get tracking perfect. Unfortunately this may not be best for the link openings. You can however purchase titanium turnbuckles for the King V2 from Xtreme productions that allow adjustments without having to disconnect the linkages.
4.13Center of
Gravity of the Heli
The center of gravity of the heli should be right under the shaft. Move the blades parallel to the heli body so that the flybar is perpendicular to the tail boom, then lift the heli by the flybar holding it near the center head. The heli skids should lift off at the same time and the heli should not tip in either direction. If it tips you will have to shift some weight. The easiest thing to move is the battery. Unfortunately, the stock battery is a little too light for the King V2. You will have to move it way forward to get a decent balance. You can add a weight if absolutely necessary. Try taping some coins to the battery. I use an 1800mAh battery and get a good CG without much adjustment.
Chapter 5 Basic Flying:
5.1 Scooting
If you skipped the work in chapter 4 you will be in big trouble because the heli will be very squirrelly. It will not respond very well to the controls. If you were able to get it set up properly you will have a chance at success in beginning to learn to maneuver/fly the heli.
Practice moving the heli forward and back first, then side to side a little (with the training gear on of course). The heli will want to move to the left naturally because of the combined effect of the main blades and the tail countering force. When you do eventually progress to the hovering stage, the body of the heli will tend to hang off center with the right skid lower than the left. This is normal. It is a good idea to practice the RADD method and keep within about a 10 foot square while starting out. Scoot on the ground within this area until you are good at moving all around. At first you should always keep the heli pointing away from you or what is called tail-in. If you get a little brave you can try adding throttle and a little right aileron (right stick) and the heli will rise above the ground a little. Bring it back down immediately. Practice this until you get the feel of hovering in one spot. I started out with my thumbs on top of the sticks. Eventually you will probably want to move to a pinch grip, but at first I think the thumbs-on-top method is easiest. It is very challenging to keep a low hover and tail-in at the same time with the standard yaw rate gyro. It is a very good idea to practice using a simulator to get basic hovering skills down before trying to get more than a few inches above the ground. If you want to actually learn from a pro try this site by John Vugts : http://www.rchelicopterweb.com/LearningToFly/LearningToFly.htm
5.2 Simulators
Using a heli simulator will greatly help you in learning to fly. I use the Real Flight G3. Clear View is about equally as good of a simulator and is only about $40US. The $20 E-sky simulator combo is really just a controller and FMS software. The software is free, but you need some way to hook your transmitter to the software. Instead of using the King V2 TX (transmitter) with a cable ($10) you can get the E-sky simulator TX for $20 and you will save tons of money in repairs. Other simulators will work too. Do some research and decide which one you prefer, but get one, you will not regret it.
5.3 - Tail-in hover, side-in hover
Practice hovering tail-in keeping the heli in one spot. At this point you can raise the hover to about a foot. If you have to abort try to bring the heli down gently. You have to resist the urge to pull the throttle all the way down quickly or the heli will hit the ground hard and damage may ensue. Eventually you want to be able to move the heli tail-in to the right and left a little. When you move the side a little you might find you are not exactly tail-in anymore. This is what I call a partial side-in hover. Practice on a simulator moving farther to the right and left, then hold it in one spot and turn lightly right or left about 45 degrees and hold it there. You have to learn side-in and unless you want to do a lot of repair work you better learn it on a simulator.
Eventually work the side-in to a 90 degree side-in. Practice right side-in until it is comfortable, then practice left side-in until you are comfortable. Then practice right side-in again. Then practice left side-in again. Do this over and over so you are not weaker on one over the other. It is very easy to think you have mastered one, then work on the other one and then think that you have got it. Only to find out it is confusing to switch back and forth and you lose control and crash. When you think you have them both down, practice gradually moving from one to the other and back.
If this is really, really hard, you might want to upgrade to a Heading Hold gyro instead of the stock Yaw Rate gyro. See the chapter about HH gyro to find out how to set it up properly. Eventually you will want a HH gyro anyway. I have the E-sky HH gyro, it works fine for my current skill level. I like the HH gyro and it was the first upgrade I made along with the brushless motor and matching electronic speed controller (ESC).
If you can perform these skills safely, then you may progress to a little forward flight, and a little side to side flying never turning the nose of the heli towards yourself.
5.4 Hovering around.
Practice hovering tail-in doing forward and back, side to side, and gradually add some shape like maneuvers. I like to practice flying simple alphabet characters such as T, upside down T, X, V, upside down V, N, M, C, L, U, W, and Z. Basically, any letter that doesnt require backtracking is easiest. Then you can do squares. Clockwise squares and counter-clockwise squares are really good practice. I have tended to lose orientation and crash when in the lower left corner of the square for some reason. I have identified this as a weak area for me, so I have to be extra careful there.
5.5 Forward flight
For forward flight you tilt the heli forward, apply a little throttle to get moving without sliding into the ground, then when you pull back slightly to stop moving forward you have to lower the throttle just a little bit or else the heli will rise because of the added lift of transitioning from forward flight in to hover again. Backward flight is pretty much about the same.
Forward flight = gentle forward right stick plus a little throttle, then gentle back right stick and a little - throttle, then hold the hover.
Backward flight = gentle back right stick plus a little throttle, then gentle forward right stick and a little - throttle, then hold the hover.
5.6 Figure Eights
If you can fly to the left, and then fly in a “C” pattern away from yourself around to where you are flying to the right, and do the same to the right ending up flying to the left, you are ready to learn “figure eights”. In between turns you just let the heli move sideways while it moves forwards from side to side. So you always end up back closer to yourself so that the next turn is the same “C” type turn away from you.
It kind of looks like this:
Get it?
Then, when you feel like it, turn the heli towards the crossing points as you approach them. Don’t even think about the fact that you are a little nose-in. You know how to fly out of it by turning away.
I like to practice a few mistakes high as they say so there is time to recover if I get disoriented or the radio glitches or something. Fifteen or twenty feet is usually a good practice height when working on figure 8s and circuits.
After a while start making your 8s bigger and fatter. The fatter they get the more nose-in you will be flying. Eventually you should be able to turn one of the sides of the eight back on itself and just keep turning the same direction for a full circuit.
Do not do any low circuits until you are very proficient at them or you will crash into the ground!
5.7 Nose in hover
Nose-in hovers and transitioning to nose-in from side-in hovers can be very difficult to learn. I think flying circuits and figure 8s is easier to be honest. So for this skill I highly recommend some sim time.
Practice hovering nose in on the simulator and then 45 degrees to one side, then 45 degrees to the other side. Eventually you should be able to do very slow pirouettes from tail-in to right side-in to nose-in to left side-in and back to tail-in under perfect control. Then work on it going the other direction. When using your real heli, take it very slow. It is best to progress at a snails pace when using your real heli. Over estimating your skill will pretty much always end in a crash.
5.8 Surviving the first crash
Trying to not crash is really the name of the game when learning, but stuff happens. When it does, you probably will have to make repairs. The first to go is usually the blades and the feathering shaft. The flybar shaft may also get bent. You could possibly strip a gear in one or more of the servos. The tail fins (aka stabilizers) are really easy to break.
After replacing the blades several times I switched to plastic blade set (~$6US). They are much cheaper and super durable compared to the stock wood blades. The plastic blades I purchased were for a Shogun type heli and I trimmed them down to 275mm using a hack saw and some sand paper so they were exactly the same shape and size as the stock wood blades. Also good are the Fiber Reinforced Plastic (FRP) blades (288mm), don’t cut these down thought because they have a foam core. The FRP blades can be purchased for ~$15. I think the FRP blades are better because they don’t flex much and I have not been able to get very good blade tracking results using the plain plastic blades. Either type will survive at least ten times as long as the stock wood replacements. Make sure to balance the blades and check the blade tracking after installing them.
Almost any crash will bend the feathering shaft. They are expendable pieces that bend to save damage to the head and/or main shaft. Buy yourself 20 or so feathering shafts, they are cheap and come in packs of 4 usually. Look on the Heliguy forum for how to replace the feathering shaft. Eventually I will post pictures and explain this. But for brevity I am leaving it out now. http://www.heliguy.com/Forum/guide-how-to-change-feathering-shaft-axis-t9807.html
The feathering shaft nuts can be removed with the aid of a 5.5mm nut driver and a set of needle nose pliers. I have two nut drivers. For installation I put them on until one end sticks out of the nut a little, then grab it with the pliers and tighten the other one until it sticks out just a little bit. About 1 thread sticking out I found is the right amount. If you have them too tight the grips will start to bind to the shaft and will not rotate free and easy as they should. Occasionally you need to use new 3.5mm nylock nuts; my Local Hobby Store (LHS) has packs of 4 of them for $1US.
Another part that may get damaged is the flybar shaft. The flybar shaft extends all the way through the head and can be bent without being noticed. This will cause a puzzling head vibration and may make the heli tail bounce up and down. After removing it, straighten it out or replace it. It needs to be really straight.
If you strip a gear in a servo it will make a buzzing or clicking noise. You can take it apart and rotate the damaged gear 180 degrees then put it back together. This trick only works one time though, so you may have to buy a replacement gear set or replace the servo. Gear sets are hard to find. A better alternative is to upgrade your servos to TowerPro SG90s or equivalent.
The vertical tail fin protects the tail blades and boom. You can replace it with the stock part or with an Align tail fin. I don’t really like how the tail fin attaches so I rigged a way to connect it to the tail using zip ties instead of the tiny screws. The horizontal fin helps in forward flight and aids in visually being able to determine the heli orientation from a distance.
Other than this use your imagination as to how to repair things. I used a piece of clear plastic hose to fix the end on the boom support that broke off. I repaired the landing skids with epoxy after a dramatic nose dive where the landing gear bit it pretty good. I drilled a hole in a control arm and ball with a small bit and CAd a pin in to keep it all together. I have new parts now for everything, but the temporary fixes seem to be working fine, so I’m saving the parts for the next occasion.
I find the sport of heli flying/fixing very fascinating. There is always something new to learn.
Upgrading:
Chapter 6 Batteries
1800 mAh batteries give good balance to the King V2. You can also get a really thin Lipo to power the TX. All you have to do is solder a connector to the battery tray. For the BL motors you will most likely need to solder on your own connectors. I use the Deans connectors, they are really tight at first but the loosen up after a few uses. Google how to solder them and there are some great videos.
Chapter 7 Brushless motor and matching ESC
Brushless motors are a great improvement because they pretty much last forever. The 3100kV and 3900kV E-Sky models fit perfectly but are slightly underpowered for 3D maneuvering. I now have the Scorpion HK-2213-14 32A motor but had to modify the frame a little to get it to fit.
The notation kV means how many RPM you get per volt applied.
Chapter 8 Head Holding Gyro
Chapter 9 Plastic, FRP, and Carbon Fiber Blades
Chapter 10 CNC swash and washout assembly
Chapter 11 Servo replacements
Chapter 12 A better transmitter
Appendix A Dimensions I find usefull
Ball size: The balls on the standard plastic King V2, Blade CP and standard CNC upgrades are 4mm. Align stainless balls are too big for the king ball links.
Feathering shaft: The thread is mild steel sized M3, the shaft has 3mm of diameter.
Feathering shaft nuts: The nylon locking nuts for the feathering shaft are 3mm nuts, to adjust them use a 5.5mm low profile nut driver. I have a good one made by Wiha.
Blade length: The stock blades are 275mm. I like the 288mm FRP blades and they are fine also. I would not go any bigger though or the tail might have a hard time keeping up and the blades could strike the boom on a hard landing more easily.
Tail boom diameter: 8mm x 317mm E-Sky 28mm Diameter 3800Kv Brushless Helicopter Outrunner Motor (EK5-0006) E-Sky 26mm Diameter 3900Kv Brushless Helicopter Outrunner Motor (EK5-0005)
Specifications:
- Length: 535 mm
- Height: 225 mm
- Main Blade Diameter: 600 mm
- Tail Blade Diameter: 130 mm
- Motor Gear: 9T
- Main Gear: 140T
- Gear Ratio: 9:140
- Weight: 470 g