belt cp vs. trex 450 for normal flight

[helibubba]

Hey guys,

I'm new at this and I bought a belt cp. I'm not so interested in 3D: I just wanted to be able to do stable, accurate normal flight. Ultimately, I'm looking to get into FPV (I don't know if any of you guys are thinking about that) which requires stable flight and longer range.

I thought the belt cp would be an economical choice for what I want. However, I'm seeing that it has some undesirable flight characteristics. It seems very sloppy. It wants to bob up and down and wander all over the place, it requires a lot serious "stick yanking" just to hover in one place and there seems to be a major lag on control input.

In looking at videos on youtube, I can see this also. Any videos of belt cp's trying to hover are doing the same thing as mine. Whereas trex 450 videos show very stable and accurate flight (like this one: http://www.youtube.com/watch?v=qHRVYZPoZ88 )

Can things like an upgraded metal head, metal swash plate, digital servos or a better controller help with accuracy in normal flight or are those just for 3D flight?

For what I want, do you think I should start thinking more about a trex 450 or can I improve the belt cp? Or, am I trying to "make a silk purse out of a sow's ear"?

Any advice will be appreciated.

[another_finn]

There's a lot you can do to improve the Belt CP's flight characteristics. The downside is, by the time you're done it's going to be a T-Rex.

Having said that, if you're new to the hobby the most sloppy and laggy component in the system is currently you. The stability in the video is not the helicopter, it's the pilot. That guy has been flying in his sleep for years to even attempt what he's doing there. Bobbing up and down and wandering all over the place is not a sign of poor quality - it's how helicopters fly until you learn to correct the motion without thinking.

You can get the same kind of stability out of a stock Belt CP, at least until the plastic wears out and you really start seeing some slop. The Belt is a good, inexpensive platform for learning on, so I would stick with it and slowly upgrade with components you can reuse on the T-Rex that you will eventually get. There's a sticky with all the T-Rex parts you can use in the Belt CP section of this forum; I would start with the Align 315 or 325 Pro blades and T-Rex main shafts. Those alone will make a big difference in how the helicopter behaves. The stock Esky servos are also among the first parts you're going to want to replace. Beyond that, it gets a little iffy. When you start thinking about CNC rotor heads and tail units, it's often a better idea to buy a whole new helicopter.

A good transmitter and gyro will stay with you through multiple helicopters, so take your time and get the best you will ever need. The stock electronics are good enough to learn on, and you will know when it's time to upgrade.

Welcome to the Esky section, by the way - there's lots of very knowledgeable guys here that will undoubtedly soon be all over this topic with suggestions and parts recommendations. Read through the recent Belt CP threads and you'll get a very good idea of what you can and cannot expect out of the stock Belt.

[DierWolf]

My belts are rock steady :)

"The better the setup the easier it is to fly"

Following the above you sould have little to no stick movement for a hover and thats the way it should be.

Yes getting a Trex Style head in itself will make things better, not necesarily becuase it is better but easier to work on and easier to see how things line up and if they are lined up properly.

Have you tried increasing the headspeed? (turning the left knob on the top counterclockwise to say 9 or 10 oclock).

Is your blade pitch the same on each blade? are your blades balanced? is your flybar paddles dead flat with no cyclic input and parrallel to the swash plate? Is your CG (Center of Gravity Correct).

My suggestion to you is to first to change the main blades and get some good align blades, the Esky stock Woodies are the worst flying blades in the world i believe, try that first and then report back.

[helibubba]

Wow, thanks for the great replies and advice! I wasn't sure if I would get any responses.

OK, I'll get the Align shaft and blades and keep practicing. Would you recommend the 315's or the 325's? Also, what servos would you recommend? Oh, and do you guys have a favorite source to buy from?

I think it's pretty well set up. I've adjusted the CG of the blades, balanced the blades, have them tracking in the same line, and adjusted the CG of the heli (pushed the battery as far forward as it will go).

I've adjusted the flybar paddles a few times and I think I have them right. Originally I lined them up with the crease in the flybar control arms (at the top) but, I noticed that the control arms (at the bottom) that attach to the swash plate were not even with each other (one screws into the swash plate lower than the other). So, now I have lined the paddles up with the swash plate using the pitch gauge. Hopefully, they're right now.

The biggest thing I've changed so far is the overall pitch range. Originally, it was really flying weird. Any time I gave some cyclic stick input, the heli would bob down to the ground and come back up. I noticed that when the battery would start to loose power, I would increase the throttle stick and the heli wouldn't bob as much (I now know that I'm not supposed to let the battery go that long). I've been reading that the max pitch range (in idle up) should be from -11 to +11 degrees. But, mine only had from -7 to +8 in idle up and -2 to +6 in normal mode (what the ???). In normal mode that 8 degree range is all I can get out of this heli. I had read that if there isn't enough pitch, you can get weird hovering characteristics. So, I now have the pitch range for normal flight from +2 to +10 degrees. In hover I guess it's around +6 degrees and it seems to hover much better now. And, I do play with the knob on the left to see where it flies better. Have you guys had similar experience with the pitch range on the belt cp?

The thing I don't like is the esky HH gyro I bought. In HH mode it's actually harder to keep steady than in rate mode. In rate mode, I can eventually get the trim adjusted so that it will hold straight. In HH mode it's very hard to get it trimmed. It doesn't seem to want to hold anything. I've tried turning down the gain some but, it doesn't make any difference. Any advice on this gyro? So, anyway yesterday I ordered at Futaba gy401 in hopes that I will be happier with it. Any advice on gyros in general?

Thanks for all your help!

[another_finn]

OK, I'll get the Align shaft and blades and keep practicing. Would you recommend the 315's or the 325's? Also, what servos would you recommend? Oh, and do you guys have a favorite source to buy from?
That extra 10 mm doesn't make much difference, but the 325s do make the helicopter slightly more stable and docile if that's what your'e after. However, it comes at a slight penalty in head speed.

The standard upgrade servos with the stock transmitter are Towerpro SG90s. Most others operate in the reverse direction, and you can't really fix that easily using the stock transmitter.

Some of my favorite Belt CP (and T-Rex upgrade :) ) parts sources:
http://www.helidirect.com/
http://www.rc711.com/
http://www.ushobbysupply.com/
http://www.amainhobbies.com/
http://www.aero-fever.net/

I've been reading that the max pitch range (in idle up) should be from -11 to +11 degrees. But, mine only had from -7 to +8 in idle up and -2 to +6 in normal mode (what the ???). In normal mode that 8 degree range is all I can get out of this heli.
I don't know if others have managed to squeeze more pitch out of the stock head, but that's pretty close to what I got - also one of the reasons I eventually upgraded to a completely different head design. I think the absolute best I could manage with the stock head and transmitter was +9/-8 degrees.

So, anyway yesterday I ordered at Futaba gy401 in hopes that I will be happier with it. Any advice on gyros in general?
Yes, but you followed it yesterday :D

The Esky HH is really hit and miss - the one on my Belt was actually pretty good, but I could never really make another one behave on the King II. Most of them will hold a heading well enough, but some of them won't let you decide which heading that's going to be. I think you'll be happy with the GY401 if you watch the Finless setup video on this site and take your time setting it up properly.

Oh, and the 0704A can sometimes be tamed by plugging the gain wire in the ground pin. This puts it in HH mode and leaves the gain pot active. In my experience, you can't really get the best performance out of them if you use the transmitter's two-position, non-adjustable switch to control gain.

[helibubba]

Awesome! Got my stuff on order all ready. Thanks.

[DierWolf]

Next best investment for the Belt is a Copter X CNC head its like 54 bucks for everything.... so if i were you when you break your first plastic head just go ahead and get that... forget about the ESky Cnc head its more trouble than its worth especially for a beginner.

You can get that or look on Xheli.com under Upgrades and Belt CP they have the blue Trex Style head for sale there for the Belt CP for dirt cheap as well.

This is that head with align 325 Fiber on the Belt CP (this is my bro's machine)

k1XVAE6ETqY

[Ian 777]

As Dier sayes the copterx head is a great upgrade (and the tail too) but you will also need
to get a different swashplate from the one that comes with the head. All Trex type head's have the antirotation pin on the rear servo link ball on the belt the servo link ball is at the front and the antirotation pin as at the rear of the swashplate. there are quite a few swash plates that are perfectly suitable and don't cost very much. The one I use is the Sonix Mini Titan Swashplate.

Fitting putting this head on will make your belt fly pretty much like a trex 450 anyway

All the best Ian:)

[DierWolf]

If you buy the one from Xheli you dont need to buy seperate swashplate, it comes with all the correct stuff..... Also XMSeller on Ebay has with correct swash already on it (thats the one in the video) this is the same people as cnchelicopter.com

[helibubba]

Thanks again for the great responses guys!

I was reading that the trex has optional flybar weights and that if you leave them off, you should get quicker response to cyclic input. So, I was thinking about getting a trex flybar and paddles and trying them without the weights. What do you guys think?

[DierWolf]

you can get flybar weights at hobby store.... Trex flybar is too large for esky head you have to drill it out a bit....

you can also add weight by coiling some heavy guage wire around the flybar next to the flybar paddle (in equal amount on each side of coz)

[another_finn]

I think you'll be happy with the GY401
Ooh, it just occurred to me... You're using the stock Esky transmitter, right? You won't be quite as happy with that, seeing as it doesn't have the remote gain adjustment you need with the GY401 :(

Apparently there is a workaround - disconnect the rudder servo, turn on the transmitter with heading hold on, connect the battery and plug the rudder servo back in. I have no idea if it works, or why...

dUOyr-Bz1rI

[DierWolf]

Gota love that Mime video, and it proves really nothing, what would prove it is if he actually few the thing.

Also never owned a King II , is that the correct musical tone for a king II when turned on? Just trying to assertain if its actual Esky equipment in there.

[another_finn]

Gota love that Mime video, and it proves really nothing, what would prove it is if he actually few the thing.
I suppose it does prove he could make it initialize in heading hold mode - the light goes solid, so at least the gyro thinks it's working. Whether the gain is something you could actually fly on is a different matter. One thing's for sure - you're not getting anywhere near the performance you could be getting with a decent transmitter.

I KNOW, I KNOW, let's not even go there :rolling

Also never owned a King II , is that the correct musical tone for a king II when turned on?
The RTF uses the same ESC as the Belt CP - that's definitely an upgrade, not that it makes any difference.

[damyxz]

Just add the flybar weights and move the 3 servo control links(z-bend)in one hole on the servo arms. This will tame the cyclic response a little and really makes the belt CP fly smoother. No need to upgrade to another head system.

[another_finn]

No need to upgrade to another head system.
...until the slop starts adding up, that is. Then it makes all kinds of sense to upgrade to something better that will also last longer. The stock head is definitely good enough for learning on, and you wouldn't really appreciate the difference until you've more or less worn one out.

The RTF comes set up pretty docile as it is, but that will certainly tame it some more. Just be careful not to dumb it down so far that the occasional wind gust has more authority than your sticks do ;)

[Grant_beltcp]

Adding weights and dampening the respones will make the belt cp as stable in a hover as other heli's, that has never been the problem. Most of us increase the headspeed to sort that problem out. The number one difference between the Trex and belt CP head is the flybar movement. A trex style head gives much more movement than a belts head, and so roll rates/flips etc all become much slower. I Have tested changing the washout arms on the belt for trex ones which does improve things a little.
I believe the belt is a good starting heli, it teaches you everything about them, and how to fly them quite well. But for any 3D flying i wouldnt touch a belt cp. The Trex wipes the floor in that area.

[rcaddik]

is there anyone here likes to post a video thats teach how to replace or change the head of the belt cp, to cpx or trex head?
that video will help those newbie like me or who's like to improve ther flights or heli....
thanks anyway

[DierWolf]

No video needed for that, simply take off the old head and put on the new.

Head removal requires just removing the Jesus pin from the Central holder and sliding it and the swashplate off the main shaft.

Reverse to put on the new head.

[thunderhead]

Makes more sense to put good servos in it to start with. Spend your cash on a good entry level computer radio like an optic 6 and a good gyro. My belt is completely stock and even with the stock blades it hovers just fine. If you intend on progressing in this hobby your gonna need a good radio.You can read all over this site about guys and their stock radios.Its not pretty.