Trex 450 Help please

[ltaylor88]

Hi i crashed my 450 clone the other day smashed blades bent main shaft, and feathering shaft.

anyhow iv replaced the parts with genuine align parts as i have many other parts always checking all dimensions with my calipers to ensure accuracy.

My problem.
after replacing the parts listed above with no alteration to setup I had 0+ pitch and crap loads of - pitch im confused it was perfect before. please help.

on a side note another thing i notice but not sure if it should be like that is the blade grips can move a degree or so with slop and also there is no trust bearing in there like the genuine align just one baring that looks like a normal one. But before this crash happened the heli flew lovely.

[MarkG_R1]

Trex 450 Help please

Can we see a few pics and have a few more details in specs of equipment?

[ltaylor88]

gl450 v2 se.
standard chinky motor and esc which seem to preform pritty well
align 780 gyro
ar6000 rx
using dx7 tx
standard tower pro on cilics and a align ds something on tail
several parts changed to genuine align. main shaft main gear tail gear shaft and a few insignificant parts.

[ltaylor88]

sorry for quality camera was going dead so flash wouldn't work

[parksy]

Hey Itaylor, First off, check length of main shaft, it may be you've put wrong size on as a replacement, they differ in length depending on model ie dfc has shorter shaft etc. Second, when you say blade grips have slop, do you mean the shaft slides in and out (oooh matron) or up and down? There should be a washer between the grip and the main rotor housing, this would take up some of the side to side slop, they are easy to lose as they tend to stick to grease on bearing as you pull the feathering shaft out and fly off into the carpet somewhere!?!??! If it's up and down, you need new bushes. As for thrust bearings, I don't know about the clone grips, but if it didn't have them before, then it's probably safe to say it won't need them now.

[Gixxer]

Linkages wrong length?
Main shaft wrong length?
Main shaft installed upside down?

[MarkG_R1]

That swashplate looks awful low considering the servo horns are near level, also the swash driver arms need to be level at mid stick

[cloudrider]

Hello ltaylor88,


The main rotor head looks similar to an Align 450SE, if the replacement feathering shaft was 3mm diameter and your description of the bearing would confirm, there are two 3x8x4mm radial bearings in each blade holder and no thrust bearing. If you don't have a manual try this link:-
http://www.heliproz.com/images/Trex%...E%20Manual.pdf
In this you will find the measurements for the link-rods. If both main and feathering shafts deformed during the crash, the servos may have sustained some damage also.


At some point you will need to learn how to set-up the swashplate using a levelling tool, it's not hard just needs to be done in specific steps. However, try this test:


Disconnect the three motor leads.
Select normal flight mode, set the head with the paddle at 90 degree to the left, gently support the flybar and move the throttle up and down through its full deflection, as you go through the mid-stick location, watch for any deflection of the paddles, they should remain perpendicular to the main shaft, do the same with the paddle straight ahead.


Move the stick up and down quickly and watch for any servos lagging.
If there is any problem with those servos replace with a set of digital servos. Hobby King UK do inexpensive fast strong digital servos they are so-much better than analog.

[cjcj1949]

Where the servos central before the crash. The swash is too low. The links fro the servos to the swash need to be longer. You may have a cross between a Sport and a SEV2. You can bodge it by setting the servos on the splines to give you 0 pitch with controls in neutral. There's usually a flat pitch curve in throttle hold.