Walkera 4#3 Tips and Tricks

[Steve Joblin]

Seems like there is a bit of a groundswell with some HeliFreakers getting into the small Walkera 4#3's now that the 2.4gHz aluminum head version (the 4#3b) is starting to become readily available at some US based e-stores and LHS's.

I've been looking at a bunch of other forums (I know, forgive me Father Finless for I have sinned) and will begin to post tips and tricks in this thread. If you know of any post them as well... maybe one day Walkera will get its own forum (hint hint Moderators!)

[Steve Joblin]

For stability and damping: longer flybar, heavier paddles, heavier flybar (all these increase gyroscopic moment), positive paddle pitch (both paddles experience upward force and will resist movement)

For responsiveness: lighter paddles, lighter flybar (decreases resistance to flybar movement due to momentum), bigger paddle area, longer flybar (increases torque moment), no paddle pitch (paddles experience opposite forces when flybar is twisted and increases resulting movement)

So, having a shorter flybar will not only reduce the stability, but also the responsiveness.

Folks have taken the paddle holders off and glued the paddles directly to the flybar... others have also used a slightly longer flybar. Responsiveness is excellent and stability is enough. Setting the flybar paddles flat will also improve the forward flight characteristics at the expense of hover stability. Angling them up a bit improves hover stability, but makes it less nimble.

Some use a steel flybar since the carbon may loose its resistance to twist forces over time. Some say that it becomes "twisty" and the heli gets unpredictable and uncontrollable.

------------------------------------------------

Someone else had these thoughts...

I did a number of experiments with the flybar and paddles to get the heli to respond more like my larger helis. I started by moving the swash links to the outer holes of the servo arms and using larger paddles from an EP-100 heli. I also increased the flybar length to 125mm. It was interesting to me that at this flybar length the paddles had so much profile drag that the heli didn't have enough power to hover and the tail response was poor. By incrementally decreasing the flybar length I found that I was able to achieve the response that I desired with a 50mm flybar and the EP-100 paddles. The heli now responds well in even strong winds with minimal stick movement.

[Steve Joblin]

This seems to be a very popular mod for the older 4#3's... I don't know if it is "needed" for the newer 4#3b's, but there is some great conversion info on "TheSteve" site at http://thesteve.ca/walkera/

[Steve Joblin]

There seems to be more and more shops carrying Walkeras in the US every day!

These shops seem to sell all the spare parts you would ever need:
www.WowHobbies.com
www.rotorfever.com
www.ka-planes.com

www.micro-flight.com (a.k.a. MIA Micro Flight) has some interesting hops such as a carbon frame kit.

Though not in the US, www.ChineseJade.com has a very solid reputation and is strictly dedicated to the Walkera and some third party hop-ups.

[Steve Joblin]

It seems that there have been many issues with motors not lasting too long. I read how one person used WD-40 spray to revive a "dead" motor.

"I can also confirm that spraying some WD-40 into a dead motor and running it a bit restores what seems to be full power to the motor. I was a bit amazed that it worked, but i guess WD-40 works as substitute for electronic contact cleaner. It is a solvent / de-greaser, after all.
I tried everything else under the sun to restore lost motors: putting some solder on the brushes, cleaning / sanding by hand the commutator, even bending the brushes on a carbon brush endbell from another motor, so the timing would be right.
WD-40 worked the best (actually, it was the only thing that worked!)"

Please note that I have not done this myself and assume no responsibility if your motor gets ruined by doing this!

[Steve Joblin]

Don't want to spend the money for a heatsink that is specifically designed for the 4#3?

You can buy a much more inexpensive one such as this... http://www.helidirect.com/product_in...oducts_id=1508

Simply cut it in half, then apply to both sides of the motor.

[Steve Joblin]

Here is an interesting mod to add tail supports... kind of gives the 4#3 a "proper" look!

It bolts on using the existing battery holder mounting screws. It uses two 30mm lengths of 1mm carbon rod and one small brass nut and bolt. The Rod fixings and boom shackle are made from 0.016" aluminium sheet.

This mod completely removed tail wag.

[Steve Joblin]

Try using part number 5560K422 from www.mcmaster.com. $7.42 + $5.00 S+H. 12 inch length, enough to make 2 tail shafts.

Specs:

Type Precision Miniature Stainless Steel Welded and Drawn Tubing
Material Type 304 Stainless Steel
Shape Single Line
Outside Dia. .095"
Outside Dia. Tolerance ±.001"
Inside Dia. .085"
Wall Thickness .005"
Length 12"
Metal Gauge 13
Temper Hard
Tensile Strength High

[CagedVR6]

Good posts, but screw WD-40, when the motor goes out, go brushless!

My 4#3b will be here Wed.

[Dusty1000]

Hi, good thread, there's not much on this forum about these great little helis.

I can confirm that WD40 increases motor life, but don't wait until it's dying, spray a little in the hole once every 5 - 10 flights and it will last a lot longer.

Another couple of tips:

Secure your tail rotor. It's held on to it's shaft by nothing but friction and can easily come off in a crash, which often results in the gear spinning into oblivion. You can use a spare canopy grommet, push that or something similar onto the end of the shaft. What I do is apply a tiny drop of superglue (ca) with a pin, to the shaft where it pokes through the rotor. Before glueing, make sure there is enough free play to ensure no binding. The rotor should spin freely when you blow on it.

Glue your swashplate to the shaft. Hold the heli in your hand, and move the swashplate up and down, using your finger on the bit that pokes through the anti-rotation bracket. You'll notice a fair amount of vertical free play. To eliminate this, apply a tiny drop of superglue with a pin to the shaft immediately above the swashplate (be really careful not to get any in the bearings). Then quickly but gently push the swashplate upwards, using your finger at the anti-rotation bracket again, and hold it there until the glue dries. Then fly it, and you should notice an immediate improvement. This is a mod you only have to do once per shaft. When you take the swashplate off for any reason, it will require a bit of a push to free it from the shaft, but when you put it back on, it almost 'clicks' into place over the dried glue.

Check your flybar pivot point. (on the A and B) Look closely at where the flybar pivots in the shaft and you'll see a tiny copper coloured bit on each side. These can come loose, though can be easily pushed back into place with a pin.

You don't want a level swashplate. Folk used to cp helis often level the swashplate when they get the heli. With fp helis there is no point, and with one this small it will veer violently to the left. It should be more or less level from front to back, but looking at the rear of the heli, it should be tilted slightly to the right. Get this correct and the heli should easily hover hands free for a few seconds.

4#3 v 4#3A v 4#3B. For anyone with an original model 4#3, the new A and B are far better, most of the heli is different and much improved. The old model could be made to hover well, but the new models are a lot better at forward flight. The A and B models fly very similarly, though there is less free play in the plastic linkages of the A, than in the cnc linkages on the B, meaning the A can be flown more accurately. The carbon flybar can be easily swapped for a metal B flybar which has slots cut for the screws, just make sure you use the screws that come with the B flybar for the paddle control frame, they are slightly longer. Also, it's alot easier to tension the blades in their holders on the A, Bs usually have loose blades.

Here's a vid to show what fun you can have in your living room with one of these



Also, the A and B are almost indestructable, they will break eventually but you can smash them off walls etc and get away with it most of the time. Being so unimtimidating also makes them really good trainers for learning forward flight and all the orientations with, I'd thoroughy recommend one to anyone getting to grips with that. Much better fun than a sim, and you are flying a real heli, so your skills will easily transfer to any other heli.

[astroflyer]

Originally Posted by Dusty1000

I can confirm that WD40 increases motor life, but don't wait until it's dying, spray a little in the hole once every 5 - 10 flights and it will last a lot longer.

yessir, wd40 and any electronic cleaner that doesn't eat plastic works well. what it does is clean the carbon buildup on the commutator caused by brush sparking during operation. rc car racers have used electronic spray cleaner to clean the comms for years. works great. carbon buildup on the comm slows current and you think the motor has died. I've done this numerous times on the same motor and probably doubled the useful life. eventually the comm wears through and then nothing can restore performance.

also I broke the carbon rod that the tail rotor and gear are mounted on. I found that a standard t-pin I use for building planks fit perfectly. I used a dremel to cut away most of the pin head leaving a small right angle there. cut the pin to length on the other side. Find a piece of wire the proper thickness. Strip a 1/8th piece of the wire insulation and push that on the end of the pin to keep the gear and rotor in place. haven't had a problem since and this shaft will never break.

[CagedVR6]

OMG thanks for the video, i cant wait until mine gets here

[Dusty1000]

You'll have loads of fun I'm sure, if you're used to bigger helis it will take a bit of getting used to something so small, though it's surprisingly stable for it's size. One tip I forget to mention earlier is this:

Turn down the EXT. There is an EXT adjustment on the 4 in 1, you can adjust servo travel to suit, making the cyclic stick as sensitive or dull as you wish. In it's factory setting you may find the cyclic stick a little too sensitive particularly for indoor flying. There will be a plastic screwdriver in the box somewhere that fits the EXT screw perfectly. If you use the plastic screwdriver you can adjust the EXT with the heli powered up, move the cyclic stick and observe the difference. Probably reducing the EXT by between 1/4 and 1/8 of a turn will be ideal.

[Steve Joblin]

Excellent tip about tuning the sensitivity using the EXT adjustment... I was wondering what that little screwdriver was for!

[Steve Joblin]

Check your 4in1/gyro to see if it's properly mounted on the frame. It must be firmly secured to the frame. The gyro is getting vibration which triggers the pulsing. Hold the heli in your hand and pinch the 4in1/gyro tightly to the frame. If the tail stops wagging than you know it is coming from the gyro. The last possibility if the 4in1/gyro is properly mounted is your head is off balanced sending too much vibrations to the gyro, so balance your flybar, check your shaft and blade tracking. If you pinch the gyro firmly to the frame and it is still wagging then try changing the tail rotor or motor.

If that doesn't work, then check that the tail boom is securely mounted and not cracked. Check that the tail rotor is on the shaft with just a tiny amount of play possible. Check for binding in the tail rotor by blowing hard on it and see if it takes at least a second to stop spinning. Press the motor plugs firmly into the sockets on the 4in1. Check for vibrations by holding the heli in your hand and spinning it up.

[Steve Joblin]

My brand new 4#3b looks to be in perfect shape, but I really hate how floppy the blades are in the blade holder... the screws seem tight, but they are still really floppy. I put about 3 layers of sellotape on the blade root and carefully trimmed of the excess tape with craft knife. This thickens up the blades in the holder. My blades still move freely like before but don't slop up and down. It feels like a much nicer fit that way.

The other idea I saw was to make a simple "washer" shim... Get a hole puncher and light card material and make a "paper washer". Simply fit it under the blade and screw through.

[Dusty1000]

I tried tape on the blade roots though I thought they no longer moved freely enough and wouldn't fold back so well in a crash, so removed it. The tape I tried was just one layer of normal sellotape, perhaps there is something more suitable.

That's one advantage the A has, the blades are easily tightened so they still swing very freely, but have next to no vertical free play.

Of course all the parts are interchangeable.

[brainlab]

Great thread!
I have just recently ordered the 4#3B also. It will be nice to have a smaller thread to reference to, rather than have to read thru the other super long 4#3B threads again.

"and here I am cluttering up this thread with my useless post "

[Steve Joblin]

Glad that folks are enjoying this thread! I've completed all 99 pages of the Part 2 thread on "that other forum" and think that I got most of the "important" things listed now in this thread.

As to my suggestion in post #16 about the floppy blades, I just "dscovered that the metal blade holders aren't as "solid" as one would think... a slight bit of pressure between my thumb and forefinger squished the top and bottom parts of the blade holder together making a tighter fit for the blade... they still are quite loose (which I understand that is what you want), but have taken some of the sloppy floppy out.

[Dusty1000]

Originally Posted by Steve Joblin

a slight bit of pressure between my thumb and forefinger squished the top and bottom parts of the blade holder together making a tighter fit for the blade..

I've tried that before and had some success too. The only thing to watch is that you get it dead even on both sides, otherwise the blades will be out of track.

BTW I'll post a link to this thread in the micro heli forum here: https://www.helifreak.com/forumdisplay.php?f=40