Rob's Hangar

The rumours have been around for a while, now we have the first picture of the new 3-axis gyroscope RX from Walkera. As per nanoheli.net the flybarless version of the 4#6 will be called 4#6S. A flybarless 4G6 is said to be in the making too.

Fits into Walkera’s platform strategy
This development fits into the Walkera’s platform strategy, in which several models are based on mostly compatible components. The collective pitch 4G6 and fixed pitch 4#6 of FP based on largely interchangeable components. For the flybarless versions merely a new rotor head and receiver will be necessary.

Megatrend flybarless
It looks like the flybarless trend is finally moving into the sub-micro area. We will see if Walkera’s 3-axis sensor RX will deliver what is expected. Besides the quality of the sensors, the software will probably be the deciding point. Whether there will be corresponding update options – we have to wait and see.

The mysterious 5th servo port
It is also interesting that there are 5 servo ports seen on the RX2433 – for the fixed-pitch 4#6 however, only 4 servo ports needed. So what’s up with the 5th port? Is it a programming adapter or is this RX also a prototype for a CP version with the required 5 servo ports?

Just got some very nicely machined parts from Hardy, including the new pitchslider and plastic baldegrips inlays. Now there absolutely no play in the pitchslider anymore. Here is a video of the double-bearing pitchslider, i also have a single bearing version which is lighter but has a little bit of play due to the use of only one bearing.

I have also installed chinese weights on the bladegrips which reduce the force needed to pitch the tailblades dramatically.

Just tested the Walkera 4G6 with HK-250 GT tail rotor grips and hub. Very nice!

The HK250 tailshaft is 2mm so i had to use some shrinktube on the 4G6 tailshaft which is only 1.5mm. I removed the hub from the original Walkera tailshaft. With shrinktube, fit is perfect and secured by a grubscrew in the hub.

The Walkera metal balllinks have been epoxied into the bladegrips. I also made some new 1mm CF tailblades with sanded airfoil. Had to use a little piece of 0.5mm CF as a space as the HK-250 GT tailblades are 1mm.

Additional weight is 1.2 gm. Result is a perfectly solid tail. Only drawback is that the pitchslider trave is slightly reduced (by about 2mm), resulting i slower piro rates. I might make a custom tailshaft from 1.5mm steel which is slightly longer than the original walkera shaft.

Now i only need the new pitchslider from Hardy and this will be the perfect 4G6 tail.

Also with Hardys blade grip mod (inlays) i will do a direct comparison between the modded Walkera plastic bladehoders and the HK-250 GT parts.

Hardy from rclineforum.de has some improvements for the sloppy Walkera 4G6 tail: Brass inlays for the bladeholders that will eliminate most of the play on the tailrotor hub are only the beginning. Then there is the custom aluminum/brass pitchslider (bearings inside) – looks like a major improvement over the stock part. Now thats some german engineering at its best! Hopefully these parts will be available soon, for now we can only catch a glimpse of the prototypes. A link to Hardy’s site can be found below the images.

You can find Hardys Website here (in german) http://www.byws.de/start.htm. Direct link to his mod (google translated) here.

Heli-Max has posted a nice promo-vid for their rebranded Walkera 4G6. Some great flying, inverted funnels and the like. I also like that they have the plastic rotor head in their setup. Nice canopy design, too.

If you’re into scale-ish looking submicro helis this is for you: Nanoheli (nanoheli.net) is developing a flexible shaftdrive solution for the tailrotor of the Walkera 4G6 / 4#6. The flexible shaftdrive is designed for the scale-ish bodies that nanoheli is offering. Also just announced is the Sikorsky S-61 Sea King body from Nanoheli.
First pics of the flexdrive shaft look promising, but we don’t know yet how the servo linkage is going to work. Lets see what Nanoheli will come up with.

Here is my Walkera 4G6 landing gear. Hybrid design made from parts of the original 4G6 gear and an old HM52#1 gear (see my older post here), held together by shrink tube and ca. The 4G6 gear is super lightweight and unbrakable and the HM52#1 mounting provides a wider spread so the heli has more stability on the ground and during landings. Total weight incl. screws is 2.2gm only, so its weight is even less then the original Walkera 4G6 LG (2.4gm).

As the 30mm wide Zippy lipos (450, 600mAh) wont fits into the stock Walkera 4G6 landing gear i have removed the battery holder from and cut the LG in the middle of the front mounting. Drilled a second whole and used a longer screw to mount it.

Now the distance between the struts big enough for 30mm Zippys. Lipo is held by a rubber band. Maybe not the most elegant solution, but less weight than any other landing gear. Stabilty of the LG is still strong.

There have been questions about how to set up the Gaui mixerarms on the Walkera 4G6 heli correctly.

When using the metal bladegrips you will need spacers in order to have the ball links exactly in the center over the flybar.
I took some M1 hexnuts, drilled them to 1.5mm inner diameter and used them as spacers. they are about 0.7mm thick, this is perfect for my setup. What kind of spacer thickness to use depends on how tight your bladegrips are on the feathering shaft, the space between rotorhead and bladegrips. 0.7mm spacers should be perfect for the stock setup. If you use the plastic bladegrips the bosses have to be trimmed down a bit.

The video shows how to check if you have the correct spacers. Notice that the ball links line up almost perfectly in the video. If they are not in line you will get friction and vibrations in the rotorhead.

Image below shows all the detail to look for.

The stock Walkera 4G6 mixer arms have way too much play, also no ball bearing. So i took some aluminum mixer arms from the Gaui EP100 V2 aka Minizoom Pro V2, part 203580 (silver) or part 203640 (black). The original ball links can be removed and the Walkera ball links fit into the threads in the Gaui parts. The Gaui parts work with the plastic Walkera bladegrips, if you use the metal bladegrips some spacers are necessary. The Gaui arms are a bit shorter but that doesnt seem to change the feel.

Result: The heli feels much more precise and most unexpected pitch-jumps are gone. Still have to shorten the plasic on the bladeholders where the screw goes in.
Thanks to Don on RCGroups – i first saw the mod from him.

Here is a video from RCGroups user jaguar_5, showing the difference: