advice on trimmimg

[tiggertoo1962]

Hi Folks,

I bought myself a Jamara E-Rix 100 Pro to practice 4-channel flying indoors over the winter with a view to getting something bigger when spring comes. I opted for the E-Rix as it had pretty good reports and was the only 4-channel mini I found for the price (around 75€). I’ve now had it for 2 days and, although it is pretty stable and responsive, I do have a couple of small things I’d like to ask advice on.
As some of you possibly already know, it has digital trimming on all 4 controls. If it spins a tad on its own axis, one click is enough to sort that out. The trimming on the throttle hasn’t had to be used, so no problem there either. Now to the problems.

1. To stop the heli flying forward of it’s own accord, I have to trim the forward/backward control all the way to the back. At the moment it’s ok, but I was just wondering if there’s anything I can adjust if the problem should get worse, as I don’t have any trim left to the rear.

2. When the heil takes off it dives about a yard or so to the left before settling into a fairly stable hover. Anybody have any idea why that would be? Sometimes I’ll find it drifting off to the left while hovering so I trim a touch to the right which usually settles it. After trimming, although it hovers fine it banks to the right a bit instead of sitting vertically. Is this ok, or will it have an effect on the flight (like losing altitude) when I want to drift it over to the right? At the moment I don’t really have enough flying experience to tell whether it’s having that kind of effect, as I have to keep all 4 of my eyes on the heli at all times
Many thanks in advance for any help you can give. I’m now really looking forward to gaining more experience with my new hobby, and can hardly wait to get good enough to take a bigger heli out in the sunshine, hopefully next spring if all goes according to plan…

Greetz, Tigg.

[jimmyhorns]

A heli is always going to drift a little. unless its a coaxial (two sets of blades spinning in opposite directions) you are going to need to put in fairly constant control inputs to keep the hover stable, so there probably isnt an issue there.

From the google search I did, its a 2 servo design to the swash, which isnt ideal for adjustment.

The two links that go from the servos to the swashplate may be adjustable, and if this is the case, try making them longer by a couple of turns, which should help with its tendancy to fly forwards.

None of this may make sense, and if it doesnt, take off the canopy and take a photo of the head section of the heli and I will draw you what I mean.

James

[tiggertoo1962]

Hi James,

thanks for the advice, I'll have a look at it tomorrow and let you know. I doubt the servo links on a 40€ heli will be adjustable but you never know your luck in a big city
If they're not I suppose I'll just see it as an opportunity to give my thumbs plenty of dexterity training over the winter

Tigg

[rudi]

When the heil takes off it dives about a yard or so to the left before settling into a fairly stable hover. Anybody have any idea why that would be?

My v911 does exactly the same. I just accepted it as a characteristic of the heli. As it is consistent, it is easy to anticipate and counter with right cyclic on take off to obtain a straight vertical ascent. I can't complain given the price of the v911.

[tomatwalden]

Left drift on take off is normal and is called "translating tendency". It's a side effect of the tail rotor. All single rotor helis do this.

http://helicopterflight.net/translating_tendency.htm

T

[tiggertoo1962]

@ James,

Well I first of all had a close look at which servo did what when I pushed which lever (helps I suppose ) then took the canopy off and - lo and behold - there was a very fine thread on the rods which I would have missed if I hadn't known I was looking for it. Thanks mate Removed the retaining screw, gave the rod 1 full turn clockwise, put it all together and now with just one click forward on the trim the bird doesn't try to escape any more. Meanwhile I've mastered a slow clockwise circle so I'm halfway to a controlled figure 8 Just the circle in the opposite direction could take a while to control properly as when I try it, the heli keeps gaining altitude cos I'm pulling with my thumb rather than pushing. Practice, practice, practice...

@ Rudi & Tom

Thanks for the info and the helpful links, always welcome. My previous flying experience was a total of about 2 hours on a 3 channel coax, so I had no idea a single rotor heli reacted like this. I've now got it down to about 15cm of drift at takeoff and getting less by the flight. Once again practice, practice, practice, but I feel as though I'm getting there

Tigg