Just ordered a Belt CPX to make a new HD Beginner Guide

[he3r0]

I would do two tests, none of them are very scientific, nor proper, i would say, but anyway,
first i would take out main blades and flybar paddles, and spin it up to 70% and higher, that would show me if vibrations are still present, also for that test i would remove training gear so heli sits firm on the ground. as for second test just try to hover it and see if it still does that.

[enigma001]

Having removed the main blades, and paddles I think I do actually have a bent main shaft? Looking straight down the shaft it looks as though the shaft is bending as it spins. This is at 70% throttle. I dont think trying the Heli without the training set and seeing if it will hover is an option. It vibrates so much that it would just topple over. What really annoys me is that I bought this Heli from a place saying it would be 100% set up and flight tested, clearly it hasn't been as I have had to spend hours trying to get it set up right! If I have to replace the main shaft, would the whole shaft need replacing or just the top section?
 

[he3r0]

yeah that looks like bent shaft, or one of the bearings is shot, next step imho would be pulling main shaft and do a "roll" test - its when you roll shaft on flat surface like glass and see if it rolls "funny"...

im sorry for your misfortune with it, but dont worry, you'll get to the crashing part later on :P (did you bought it used? or spanking new?)


quick edit, before you pull the shaft completely, pull the head out of the shaft, and spin it again, to rule out f-up head.

[pinguin6218]

Looking from the video, everything below the center hub is ok. Straight shaft.
So it's hard to tell if the tip of the shaft is bend or you have problem with the center hub.
Check your shaft like he3r0 suggest. If your shaft is ok, so you have problem with the center hub.

[enigma001]

I have a replacemnt ESC which I want to install. The ESC has 3.5mm male bullets. I have found an adapter by Great Planes 3.5mm bullet to 2mm female which will fit onto the esky motor with no need for soldering or removing the original motor connections. Can anyone tell me if using such connections are ok, or is it better to solder new 3.5mm connectors to the motor?

Here is the website I found them ... http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXPCE8&P=ML

[pinguin6218]

I prefer to solder a new 3.5mm conn.

[Gene T]

As long as the wires are short you're not likely to lose much to the adapters. If you don't want to solder, I think you should be fine using them.

[enigma001]

Finaly got my heli fixed up and has no vibration at all now. Even though my main shaft and feathering shaft seemed fine on the "roll" test I replaced them anyway and now the heli is much better! Would like some advice on setting the swash height... should the swash be as low as possible in idle up and it mid stick throttle - so that the swash is nearly touching the collor holding the main shaft? My servo arms are @ 90 degree, swash is nice and level etc.

I went ahead and used the great planes adapters and they work great. I have no problem with soldering, I just didn't want to damage the quality of the connection in anyway by removing the original connections then resoldering new ones!

[enigma001]

Finaly got my heli fixed up and has no vibration at all now. Even though my main shaft and feathering shaft seemed fine on the "roll" test I replaced them anyway and now the heli is much better! Would like some advice on setting the swash height... should the swash be as low as possible in idle up and it mid stick throttle - so that the swash is nearly touching the collor holding the main shaft? My servo arms are @ 90 degree, swash is nice and level etc.

I went ahead and used the great planes adapters and they work great. I have no problem with soldering, I just didn't want to damage the quality of the connection in anyway by removing the original connections then resoldering new ones!

Forget to mention also... when I move the elevator stick to its lowest position I get some servo "buzz"

[Infinite_Day]

When the swash is at it's lowest limit do you have any binding throughout the range of the cyclic? It shouldn't hit the main shaft collar. Do you have a pitch gauge? You should have equal positive and negative pitch in idle up mode. It's not 100% necessary for these to be equal if you aren't doing 3D but you do need to have enough + pitch to get airborne and if the swash is set too low you won't. Either way, you want to have 0 pitch at mid stick. Hopefully this makes sense and helps some.

[enigma001]

When the swash is at it's lowest limit do you have any binding throughout the range of the cyclic? It shouldn't hit the main shaft collar. Do you have a pitch gauge? You should have equal positive and negative pitch in idle up mode. It's not 100% necessary for these to be equal if you aren't doing 3D but you do need to have enough + pitch to get airborne and if the swash is set too low you won't. Either way, you want to have 0 pitch at mid stick. Hopefully this makes sense and helps some.

Thanks for your reply Infinite_Day  - Yes there does some seem to be some binding or something making the servos "buzz" can't quite work out where its binding though? In idle up with my swash at its lowest point which is with throttle stick right down - When I move the aileron stick left or right I am getting servo buzz, also when moving the elevator right down Im getting buzz. I do have a pitch guage and have set to 0 pitch at mid stick idle up, and get -7 pitch at lowest stick, however with the stick right up I get +10 pitch on both blades. Below are some photos showing the height that my swash is set at in idle mode.

http://img688.imageshack.us/i/p1010046da.jpg/

0% Throttle

http://img140.imageshack.us/i/p1010047s.jpg/

50% Throttle

http://img571.imageshack.us/i/p1010048v.jpg/

100% Throttle

[Infinite_Day]

Buzzing doesn't mean something is wrong. Digital servos will buzz with just a bit of pressure and it's not a problem. If you're not doing any 3D flying and you have +10 pitch, I would not worry about it and just fly it as is. You could take the time to even the pitch out but it's not necessary. I don't think that +10 is so much pitch that it will make the heli more difficult to fly than a Belt typically is. I have a Belt CP and it has +9 pitch maximum.

[jorrick]

KICK

hello, the Belt CPX dvd... does it also contain instructions on how to setup the Belt CPX with a DX6i ?