View Full Version : T-Rex 450S build question(s)

07-15-2007, 08:13 PM
Hi all:

I've nearly completed building a T-Rex 450S but I have a question or two.

1) Should the rudder control rod guides be glued to the tail boom? Maybe I missed something but the control rod guides move around a lot and that doesn't seem right.

2) Should the rudder servo be providing ful rudder movement both ways or should I be favoring one direction to account for main rotor torque? I read this section in the build manual but I'm having trouble comprehending it.

3) How are T-Rex owners securing their flight battery? I can't seem to come up with a workable idea.

I got a DX6 to go with the T-Rex 450S and got it set up correctly to mix the three main rotor servos after some trial and error.

Mounting servos was really hard, maybe there's a trick I missed, I'm not sure. I had to re-animate houdini to get the self tapping servo mount screws and nuts installed.

Today I want to align everything, wish me luck.

Heli Jim
07-15-2007, 10:44 PM
Check out this link to HeliFreak

Their forums have sections devoted to TREX helis and there
is a lot of information there for you


07-16-2007, 12:27 AM
I'm getting there.

I worked out how to mount the battery. I also think I've got the rudder setting correct, though I'm not positive yet.

I still haven't glued the rudder shaft guides into place just in case.

I have a weird mixing problem though. When I push the DX elevator forward towards the top of the transmitter, the entire swashplate moves up instead of just the control on the elevator servo. Any ideas about what I'm doing wrong?

The rest of the controls appear to be correct.

07-16-2007, 02:37 AM
I found a proper setup guide. Mixing problem solved.

Now I'm re-charging the transmitter batteries so I can set the sub trims.

09-23-2007, 07:41 AM
You use a tie-wrap on the guides. Insert it under the slot between the guides and the top of the boom, and friction will hold it in place.


09-23-2007, 07:41 AM
Don't glue them in place, as you will need to move them easily when you crash.

09-23-2007, 07:41 PM
Hi all:

As it turns out I did crash and have since replaced most of the parts. The T-Rex appears to be properly set up again, but I've not had time to fly since staff and students have returned to work.

Tomorrow there shouldn't be any students around since it is a non school day for them. I may have to take the T-Rex and my Cessna 210 to work with me.