Great Wall : Xieda 9958

[RoboHeli]

Sounds like you've got a great plan. I really enjoy Phoenix with the DX6i. I can't wait until version 4.0 of Phoenix is officially released. I'm hoping that they add a bunch of new helicopters to the mix (I want the mSR X and mQX!) Of course, it's already got a ton of great CP helis so you'll have plenty of 450 variants to fly there.

FWIW, the Turnigy 9x will also control the WL V911 which is also another great little cheap FP heli like the 9958. I plan to ultimately get a few of these cheap birds and mod them so I'll have the 9x to control a small group of them.

[MESummersII]

Update: Got the 9958 and it was a nice little FP heli. I went through three batteries a night for the first three nights and really saw an improvement in just working on hover and orientation. I fount a weak spot though...the tail rotor and fin are attached to a small plastic bracket that can actually slide on the tail boom. Just took once going down a bit disoriented and landed angled backwards and it pushed the bracket back about 2 cm which was enough to cut the really thin motor wires for the tail motor. Gotta try and find a replacement now

[RoboHeli]

Oh no! Yeah, I've heard of this happening. When you replace it, try putting some heatshrink or something around the tail pieces so that this won't happen again.

You'll have to resolder the wires though since this cheap little heli doesn't have a plug on its RX board like the more expensive MSR.

However, I might suggest that you look into purchasing a Nine Eagles Bravo SX tail:

http://www.clubheli.com/Bravo-SX-Tail-Set_p_2863.html
(they're in PA at least so shipping won't be terrible!)

I've heard good things about this tail from some of the rcgroups.com users. It's more powerful and responsive.

Otherwise once nitroplanes.com gets their tails back in stock:

http://www.nitroplanes.com/27p-9958-24.html

you can get them there. When all else fails, I typically go to myrcmart.com (paypal). They're in China but they're cheap and so far have been reliable in my experience (and others...)

[MESummersII]

Yeah, I saw that tail on rcgroup...I did check out those threads. I was somewhat worried as a newbie that a more responsive tail might make it a bit harder for me to control but I decided to give it a shot. For $4.50 it isn't breaking the bank if I have to replace it again. It has been ordered. I wonder if I could mod that Bravo SX body to fit on the 9958 (once I get better at not crashing...).

[MESummersII]

Got it all together with the Bravo SX tail. Works great. Definatly give the tail a little more umph. Only two small issues I've noticed. One, the tail boom is longer for the Bravo SX so it throws the CG off and tries to pull the tail down...really had to add alot of forward cyclic trip to keep her level and not drifting back. Also, just an aesthetic thing, the Bravo SX uses a full fuselage so the tail fin won't fit on that boom.

[RoboHeli]

Good to know!!! Thanks a lot for the update. Did you adjust the servo arms to compensate for the CG shift?

Also, is it possible to just replace the motor with the Bravo SX one and use the 9958 boom tail? Or do you have to do the entire assembly?

[MESummersII]

I did not adjust the servo arms...I was able to get it with the trim. While I suppose adjusting the arms would allow a bit more total servo movement it would more allow me to nose down further...something I am definitely not in need of at this point and flying in doors. It is plenty fast enough.

Also, it would be possible to swap just the motors out. You would have to remove a small tab that is suppose to hold the motor in on the 9958 because the SX motor is just a bit longer however I think it would work fine still. That tab doesn't really hold well in the first place and it wouldn't be hard to put a small drop of glue to hold the motor in just in case. I might be tempted to try it when I have a bit more free time.

[RoboHeli]

Sounds good. I asked one of the resident 9958 experts about this over on rcgroups.com and he had a good response regarding swapping alternative tails. Here's the direct link to the post:

http://www.rcgroups.com/forums/showp...postcount=5238

the content of the post from Daryoon:

The Solo Pro, Bravo SX and 9958 all use the same width CF boom. (1.7mm)

Therefore, they all can fit the 9958's tail fin.

The Bravo SX has the longest boom.
The Solo Pro is slightly longer than the 9958.
The 9958 has the shortest boom. However, it's tail motor mount is longer. So the entire tail assembly of the 9958 is about the same length as the Solo Pro's tail assembly.

I assume you'll use the 9958's tail motor mount because you want to keep the tail fin.

For the longest tail assembly. Get the Bravo SX boom and put on the 9958's tail motor mount.

Here's the page of the thread where this post came from:

http://www.rcgroups.com/forums/showt...54770&page=350

and the full 9958 thread:

http://www.rcgroups.com/forums/showthread.php?t=1454770

[MESummersII]

Thanks for the info, I'll have to take a look at that. The issue with the 9958 tail motor mount is that it's design that allows it to slide up and down the boom freely is what caused me to cut the motor wires. Granted this would not be an issue once I don't crash quite as much but if it gts bumped on the back too hard it slides the motor mount down the boom and the wires just aren't tough enough to not get cut on the tiny edge of the small boom. And the opening is way to small to try and shrink wrap the wires. I haven't had a ton of time to look at it so I will have to look more closely tonight or tomorrow. I could be missing a simple solution. (Other than the obvious not crashing it...)

The issue with the fin is that it mounts to the 9958 tail motor mount...not the boom itself. So you have use the 9958 motor mount for the fin to work.

[RoboHeli]

Here's a link to a fix that you can do to help avoid severing the wires in your tail:

http://www.hacksmods.com/2012/01/xie...or-holder-mod/



Do a search for 9958 in that site. There's a ton of great info there about modding it.

Here's the returns of that search:

http://www.hacksmods.com/?s=9958

Scroll down through them to see them all and then there's a second page (so far) of 9958 goodness that you can get to by a link at the bottom.

[MESummersII]

Awesome. I actually swapped them out and used just a very tiny drop of CA glue to hold it still. As cheap as the parts are I can stand to have to order a new boom if I can't get it off and I figure if I crash hard enough to break that loose most likely something else is going to break too. The shrink wrap is a good idea but I didn't have any handy. I'm new enough in the hobby to have not built up a supply or random things like that yet.

[Eddie Komst]

Hey all, new old guy here.
For $39.95 plus postage from Xheli(shipped from CA) this bird is the "most bang for your buck" I have seen so far in the hobby. Its a near clone/cross of the Blade mCX2/mSR. Its cons are the plastic used in construction is not as elastic as the Blade models. The connector balls and center spindles on the rotor blades are the first to snap off in a crash. Next would be the landing skids. The pro is you can replace the rotor blades with those of the mCX2 which is the bird I cut my teeth with and after MANY crashes have never broke a rotor blade. The landing skid for the mCX2 looks the same at first glimpse but the battery mounts are placed a tad forward and the batteries will make contact with the servo gears. Also the pins are smaller on the mCX2 skids and will fall off more easily. The 9958 will take E-Flite 150mh li-pos no problem just don't charge the E-Flites with the USB charging cable supplied with the 9958 or you'll cook them. The stock li-po for the 9958 seems to have a built in voltage limiter hence the longer black collar on it. The 9958 li-po will charge fine using the E-Flite Celectra charger @ 0.3amps.
In addition to replacing the rotor blades with the mCX2 rotors, I replaced the fly bar with the Blade mSR mixing flybar and it seems to have doubled the speed and response(sort of like moving to the longer swash plate posts on the Blade models). The xmitter supplied with the 9958 looks identical to the MLP4DSM but will not bind to Blade helis and vice versa. Also, it takes 6 AAs and charges the li-po using the USB cable. Even the xmitter seems to be a more brittle plastic than the Blade xmitter as I have broken off the left stick being a bit panicy flying in my small living room. Being polystyrene it was easily glued using plastic model cement. I also re-inforced it with 5min. clear epoxy. I heard were a number of "pilots" who orderd their 9958s from helipal in Hong Kong recieved a type 1 xmitter(throttle on the right). The left stick is pushed in to bind the xmitter to the heli but I found it never seems to lose its bind no matter if you shut the xmitter off first or not. It also serves as the high/low rate selector unlike the MLP4DSM that uses the right stick"button". It seems to have a huge difference betwen high and low rates and there is no indicator of high or low except for a single beep for high(the default) and a series of beeps for low. The included instruction manual is in Chinese and English but the English half is loaded with Grammatical errors sort of like a really bad Chinese menu! Still, its understandable with repeated readings. All in all this bird is a great way to graduate from co-axial helis to fixed-pitch single rotors for flying in small spaces. Very stable with its original flybar installed. I started the hobby with an mCX2 and yearned for a bigger bird and a FP single rotor so I went and bought a Blade 120sr. It scared the heck out of me! It will either wreck the house or kill the cat in my small apartment. Now I'm waiting for a windless day to take the 120 outside and the Xieda 9958 satisfies my craving to learn FPSR in the house! Overall the 9958 is well worth it even with its brittler plastic. Bravo Xieda!

[ekphoenix]

Originally Posted by MESummersII

Yeah, I saw that tail on rcgroup...I did check out those threads. I was somewhat worried as a newbie that a more responsive tail might make it a bit harder for me to control but I decided to give it a shot. For $4.50 it isn't breaking the bank if I have to replace it again. It has been ordered. I wonder if I could mod that Bravo SX body to fit on the 9958 (once I get better at not crashing...).

I've successfully modded the Bravo SX body to fit my Xieda 9958. Check it out.

http://thefibonacciphoenix.wordpress.com/

[RoboHeli]

What a great blog post!!! Thanks a ton for sharing this. I'm going to repost your link on the 9958 thread in RCGroups as those guys there are going to like this.