| |
| Wespen | Heliman - Location: Zagreb, Croatia - |
Performance in a small package
Is it freezing outside? Are your thumbs cold and numb? Or you just want to experience flying inside? I have just a thing for you, sub-micro 3D heli, the Gaui Hurricane 200. Don’t be fouled by its size, this is not co-axial Lama, Sabre/Blade CP or Apache Attack Helicopter you can find in toy store, this is full blown 3D machine. It features CNC head, 120°CCPM swash, carbon frame and tail belt drive. It’s your big heli shrunk to 200 size with all bells and whistles. Inverted reverse, piro flips, funnels you name it, small Hurri can do it.
This Hurry comes from Infinity-Hobby (http://www.infinity-hobby.com) and it’s a Kit Combo deal with everything you need to make it fly, except your TX/RX. If you fly big stuff take this combo coz you won’t find spare electronics lying in your garage and no 2100 Lipo or S9650 won’t fit on it. What you need is pico or micro sized stuff.
  
Size comparison with T-Rex 450
For us non-Americans shipping from USA shops actually takes longer than Asian retailers and with recent USPS unpopular prices its way cheaper. In my search for cheapest T-Rex parts I found Infinity and this is where their Hurry 200 kit combo caught my eye.
The kit comes with 3 GWS pico servos, Heading Hold gyro with Hitec HS-55 for tail servo, Gaui 12A ESC with matching 4800KV brushless motor and 800 mAh 2S Lipo.
Now don’t go compare it with cheap RTF co-axials, this is a real heli. Yes it costs just like bare-bones 450 sized but this is as much heli as its bigger brothers and its RTF.
Small storm
Hurricane 200 is evolution from EP100/EP100Pro line with new frame and all of the upgrades in one place. It’s turning 200mm blades over 3000 RPM and with 800 mAh lipo you can have fun from 4 to 6 minutes. Just be sure to buy some more lipos, make em a bit bigger while you at it. 1000-1100 mAh will last longer. The frame is 34mm wide, inner side to side, so dimension your lipos accordingly.
Precision machining is stunning on these small parts.
It features full carbon frames and carbon quality is top notch. I had a friend who is building 2.6m scale carbon fuses for Extras and Caps come over to check this small frame. He said quality and finish is great, no air bubbles, good stiffness and its light. Machining and cuts are solid with no fraying, good enough for me. The whole frame when assembled is rigid, with no flexing.
Head is downsized full Bell-Hiller setup with overslung flybar just like the big birds. Main shaft is supported by 3 bearings which you don’t see often even on bigger helis.
There is a bit of slop in the head, resulting in a few degrees on play on the flybar pitch. Most of the slop is coming from the washout block bushing which has some free play on the shaft.
Not to worry about, same thing was bugging me on my T-Rex, I even go and checked the Hirobo Leptons head (they say it’s the best quality) and it was almost the same.
Tail is belt powered but tail gear is fixed to main gear so make your autos low. Head will keep spinning without power but tail hold wont last long.
I don’t prefer batman vertical fin, but its personal preference so I won’t take this as a bad thing. Servo links are direct to swash, true eCCPM setup.
  
Tail pitch slider is Raptor/T-rex 450 V2 style for minimum slop.
To sum it up, it’s like big heli just shrunk to micro size, 250 grams to be precise.
The build
As little Gaui comes pretty much assembled there is not much to do. You need to install electronics and you are ready to go. You really need some small screwdrivers and patience or you will be searching parts all over the floor. Manual is a bit sparse and all the text is on Chinese with just exploded views and parts numbers. If this is not your first heli you wont have any trouble getting it right, as for others check http://www.gaui.com.tw/en/200h.htm for updated manual and spec.
I rechecked the frame screws and switched my attention to the head. It wasn’t really spinning free and the pitch change was a bit stiff. I found out that bottom collar was a bit tight on the bottom bearing so I loosened the grub screw and push the collar to the bearing with a bit less force. Tighten it down, no up/down play and shaft was now spinning free. Moving on up, after rechecking all the links I found out that the problem was in only one tight link that made the whole head stiff. It was the short one from the flybar to blade holders. I poped it out, cleared a bit of flashing from the mould, put it back on and problem solved. Nice and free. Be sure to check yours.
Electronics
Moving on to electronics. Since the kit comes with GWS pico servos so that’s what I will be using. They are fairly fast at 0.12sec@60° and weight only 5.4 grams, perfect fit. The frame looked a bit weak at the front servo mount but the servos tight fit stiffened it up.
Mounting screws are just a hair too small and since I’m not a fan of self taping screws in carbon frame I had to do a mod. Using my trusty old Dremel I widened the mounting holes to M2 size and used screw and nut to secure the servos. I ditched the brass bushings and use only rubber grommets since standard M2 hex screw head was big enough. Tight and vibration free but still enough flex so you don’t rip your carbon frame in a crash. Remember, lower servo on the right side to avoid clicking on the main gear.
Setting up CCPM took some time. There is just one image on the swash setup page in the manual and its only height measurement from the frame to the swash. To help myself I trimmed a small piece of balsa to the correct height (saw it on one of the forums) and leveled the swash on top of it. It made things a lot easier.
Elevator link length adjustments are hard to do in such a small place so arm yourself with patience and enough time to set it up right. Pitch and aileron balls are second hole from the center and elevator is 3rd, which gives perfect link setup.
 
To balance everything out I put ESC and RX on the front tray. Since Im using 2.4 GHz gear no probs with interference. 12 amp ESC is attached to the left side with velcro and secured with zip tie and small Ar6100 is velcroed vertically to the front. I’m a bit of a “clean install freak” so this setup will give you nice wire free looks.
   
I wanted to put the gyro on top, in the middle of the frame sides, but I changed my mind and put it outside on the left frame. The top position was perfect, but since frame screws were there it wasn’t totally flat. Also there wasn’t much clearance from the frame sides and I didn’t want to fiddle with vibrations in such a small place. Ahhh, to tell you the truth, I couldn’t run wires to the RX nice enough (they were just a tad to short) otherwise I would put it there.
With the gyro on side wires were straight run to the front. I put the wires in black shrink wrap so you won’t even notice them. If you don’t mind spaghetti wires you can put it between the frames. Futaba 401 wont fit there BTW. I used that top space and tuck excess tail servo wire in big shrink warp and fixed it there. Good thing canopy is covering a lot of frame so you won’t see ESC or any of the wiring. As I said, nice and clean. 
Tail setup
First of all, I considered Hitec HS-55 0.17 transit time a bit slow. You will probably be ok with Hitec for basic stuff, but since this is 3D machine you will benefit from faster servo. I plan on putting fast digital there in the future. There are some nice (and cheap) Arrow or Ino-Lab digitals in 9 gram range.
You really need to set the tail up mechanically perfect to make it work without drifting on NT-400 gyro. You won’t get tail pushrod parallel to the boom because tail pitch arm is a bit off, but you will make it close enough. Just watch out pitch slider arms, if you move them too far to the boom they will jam the slider. I’m not sure is it design “feature”, so note to GAUI a tad longer arms will not bind. Put the gyro to rate mode and adjust the pushrod length so you aren’t drifting in hover. After you adjust it the gyro will hold. It will take you some trial and error to make it right. Be patient with the gyro as it needs some time to initialize Heading Hold and it will light blue when it’s ready (Gyro instructions are also all on Chinese so I roamed the net to see how it’s set up). Since servo mounts on top of the bracket clamp and clamp screws are now below servo tabs, adjusting the tail mechanics is a pain. Unscrew servo, unscrew holders, move the clamps half mm, screw them back on, screw the servo and while doing so you moved it back that half a mil. Rinse and repeat. It would be better if the clamps mount screws go the other way around. Since Hs-55 horn was rubbing the tail boom I had do swap the clamps vertically to make some space. This also made the tail link more parallel to the boom. NT-400 locks the tail pretty good. Nothing spectacular, it will give a bit on full pitch pumps, but it copes with the little Hurri well.
A few posing shots
Time to fly
I really wasn’t prepared for a big storm in the small Hurricane. I knew it would be twitchier than bigger helis, but this is INSANE. I ended up at 50% D/R, around 60% exp and reduced the pitch on DX7 CCPM mix menu to 40 to make myself in control. I have a bit more cyclic on idle-up2 but you really need to be ready for it. On full rates it would flip in a blink and do a loop on the spot. Toned down its pretty stable and controllable, really a blast to fly. I was doing covert ops mission in my living room, landing on dining table and doing popups behind my flower tree line (yeah, my wife killed my when she found out). Yes, it can do all the fancy stuff you see on 3D Masters and YouTube, but you knew that already. You just need to practice and clock some time with it to so you don’t do 3D allover the place.
 
Its really crash worthy, on my first flight I met up with the wall, no damage, just a ding in the blades. This plastic blades are really hard to crash, they flex a bit (well its not carbon) but can take a lot of punishment and still keep you flying which is not the case with landing skid. It breaks on first hard landing. Good thing spares are really cheap. Spare landing skid set is 3 $ at Infinity.
To sum it up
Winter flying here I come, and guess what I don’t need gloves
Small note: After first flight I removed the stickers I put on the blades as it messes up their balance.
Pros and cons
I won’t be mentioning its size, since you already know its small and you know how small helis fly.
Pros:
All blinged up like big birds
Fit and finish
Cheap to run, plenty of replacement parts from EP100 line
Extreme fun to have
Cons:
Tail servo clamp positioning is a task of its own.
Tail pitch slider arms will jam if driven too far
Will piss of your wife if you start buzzing in the house
Link to the original size picture gallery
http://www.23hq.com/RCReviews/album/2738558
Wesp |
| 01-02-2008 10:11 PM | | | |
