Some help please

[Mack]

Hi All
I am busy fitting the servo's to my Nexus. The servo's came with round/disc shaped levers. In the kit there are star shaped ones. Do these have to be put on? There are also little square rubber gromits with the star shaped levers, what are these for.
Starting to think I should have bought a ready built heli!!
Thanks
Mack

[Stuart]

Once all servos are connected and the transmitter is set with all curves linear.

All arms on the servos are off, turn it all on. First Tx then Rx now the servos will all be in centre, place arms on to give a true curve in both directions with equal distance on movement.

Then start the connections to the swashplate, for me with the servo's center I want zero pitch, so I mechanically setup the heli so that with servos dead centre and equal travel in both directions I have zero degrees at the middle and +/- 10 degree's.

The arm choosen is dependant on which give me the pitch I'm looking for, thankfully for me the Robbe heli is very much setup as the manual say's so its a simple decision as you will see below.





The diagram above shows you how the rubber gromets and eyelets are to be used.

[Mack]

Hi Stuart
Thanks for the help. I will need to take all the servos off again to fit the gromits. This will not be the first time!
Thanks again.
Mack

[Mack]

Hi Stuart
I have been reading about all the radio equipment recomended on this site.
I have FP S148 servos and not once are they mentioned, are these OK?
Just to put you in the picture, I am building the nexus over a few months, but also have an old EP Concept that I am trying to learn on :x . Parts for this are few and far between, so I am very reluctant to get brave.

[Dedcalm]

Hi Mack, I have a Nexus on which I have used 148's for all but the rudder servo.

Some people say that s148's are only good for throttle and to use 3001's as a minimum. The 3001 is a ballraced version of the s148. These are the budget end of the Futaba ranga and their price reflects this but saying that 99% of my fixed wing aircraft use them and also my Nexus.

There are perfectly ok (in my opinion) for use while learning although once any 3D flying is done you may find the s148's dont have enough speed/torque especially on the collective pitch. Also the s148 is not really fast enough for the tail but again ok while learning although its life may not be as long as a dedicated tail servo (e.g. Futaba 9254).

Like I say I have been flying s148's for all but rudder on my Nexus for 3 years and they are still going strong When I changed the standard Gyro to a heading hold one I also upgraded to a fast digital servo for the tail.

My new Raptor 50 has digital servo's throughout (apart from the 3001 on throttle), with 9252's on cyclic and collective and a 9254 tied to a GY401 gyro for tail. The larger the heli the more that should be spent on the servo's.

Hope this helps a little, if you have any Q's about the Nexus etc let me know

Rob

[Mack]

Hi Rob
Thanks for the help. I have now fitted all the servos properly and connected the rods. The radio I have is old and has no notes on how to connect the reciever and servos that I am using. Will it be OK to connect each servo seperatly into the reciever until I find out which servo goes into which channel on the reciever.

[Stuart]

Mack,

It should work like this

Ch1. Aileron
Ch2. Elevator
Ch3. Throttle
Ch4. Rudder
Ch5. Gyro

This is dependant on what Tx you have and what mode you fly....Mode 2 is the norm with.....

left stick = Rudder / Throttle & Pitch
Right stick = Aileron & Elevator

Provided you don't have the engine running

Set up with the Tx and Rx on and plug in the respective servo's into each channel one by one (Your Rx should have this clearly marked) until your channels are all setup correctly, then get cracking on setting up the servo throws, and pitch settings.

[Mack]

Hi Stuart
Thanks for that. Going to start right after dinner. I think it will still be some time before the engine gets started.

[Dedcalm]

Note that channel 5 (gyro) would only be required if you have a dual gain or heading hold gyro. If you have a standard gyro (CSM180 or similar) then the gyro would connect to CH4 (rudder) with the rudder servo connecting to the gyro.

Hope that is clear

Rob

[Stuart]

Good point on the ch5....well spotted

[Mack]

Hi Rob
The gyro I have is a ICG 180, so I suppose it is a standard one.
Thanks for pointing it out.