FMS 1400 P51D

[Grossman56]

Hi Guys:
I was getting the new receiver in the Mustang and playing around with the controls. I noticed that the throw on the elevator is about 3/8" up and 3/8" down which seems to me to be very little, compared with the rudder which has better than an inch either way. I tried unhooking the push rod and worked the elevator by hand , then activated the servo with nothing attached to it, but it still doesn't move very much. I'm thinking another faulty servo. Since I get great throw from the rudder, I wonder if I couldn't get the same servo for the elevator. The Elevator is an FMS 3103 and the rudder is an FMS 092, any thoughts?
This is full up



And this is full down



I have the Travel adjust set at 125% as well

Grossman56

[StarHopper]

Re: FMS 1400 P51D

Hi G-man,
First I'll say, if you haven't got a servo tester, GET ONE! Or two or three. <smiley image="smiley_happy.gif"/>
Can be had for <$10 & are indispensable, especially when setting up a new plane.

Wish I could be there to see it first hand, but trace back thru the linkages/pushrods et al & the angles involved. First impression is you aren't 'apples-to-apples' in comparing elevator to rudder. Elevators don't generally need much movement to do their job, unless it's a 3D plane. But for a quick cure, easiest way to increase the range is to move in one hole on your control arm. Same effect by moving OUT on your servo arm, but most setups start there so, might not be possible without adding a longer arm or extension.

One thing you can do w/o the tester -- try grabbing the servo arm while you manipulate it with your Tx and check its 'oomph'. A good servo will be pretty hard to stop completely - if it does stop with minimal pressure, it's probably kerplunk.
(While testing, don't actually stop/stall it more than a split second!)

[Grossman56]

Re: FMS 1400 P51D

thanks for the tip, I'm slowly collecting all the testers and meters, but I'm going to order a servo tester right now. I unhooked the control rod and worked the elevator by hand to see if it just needed to be worked in a bit, then unhooked the pushrod from the servo to see how much movement was there, and it wasn't much. I'll try what you suggestd and see how much oomph its got
Thanks for the help!

Grossman56

[Grossman56]

Re: FMS 1400 P51D

Update:
I was installing the Spektrum AR 635 receiver. The problem is that I didn't have it set for Sport Mode. We were struggling to understand it last night, so took the manual to work and studied it at break. What I had to do was go back into the reverse folder in my receiver and set everything back to normal. Once I did that she programmed up to sport mode just like the manual said. Now the elevator jumps as expected. Then I went back into my receiver and reprogramed the aileron and Elevator reverse. All is well, thanks for your help, I ordered a servo tester, not going to be caught like that again.

[StarHopper]

Re: FMS 1400 P51D

<smiley image="smiley_super.gif"/>