Baron’s Hobbies – Online Hobby Magazine

Align T-Rex 450 Pro Super Combo- Build

Posted on September 30, 2009 by aaronredbaron

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In our last article we introduced you to Align’s most performance oriented 450 to date, the T-Rex 450 Pro. With an all new design by Jason Krause, the T-Rex 450 Pro is a far cry from Align’s heli origins. As you can see in our intro to this review, upon opening the box there is not a lot to complete. In fact, I was able to build the entire review model, including taking the pictures, in one afternoon.

Sub-Assemblies

Opening the box reveals a well organized package with mostly pre-built sub-assemblies. The main frame, rotor head, and tail come pre-assembled. Foremost on my mind was whether or not the builder used thread-lock on the screws, or as the manual states; “For original manufactory package, if the product is already assembled by Factory, please check again if screws are firmly in place and applied with some glue.”  Despite the poor grammar, their point is fairly clear. Checking many random screws, I found all of the pre-assembled parts to have thread-lock on them. Having found thread-lock on the screws, I was satisfied I could proceed with the construction. The manual reads as if the the model were in full kit form with nothing pre-assembled. Its sure to help with rebuilding the model later after a crash, and easy enough to skip over the assemblies steps already completed.

Main Rotor Head

With everything secured in place, the main rotor head leaves little to be completed. With one piece fixed length control rods for the Hiller input and the link from the Bell/Hiller Mixer to the blade grip, there is a lot less assembly of control rods than most models. Only the Bell input is adjustable, which is where the blade tracking adjustments are made. All the ball links operate exceptionally smooth with no slop.  Machined aluminum is used throughout on the head; its anodized black with some areas machined to show off the aluminum underneath. All the mixing arms have dual ball bearing support, and even the washout links are supported by dual ball bearings where they pivot on the washout arms. Two ball bearings and a thrust bearing are mounted in each blade grip, these should be inspected to make sure plenty of grease was used on the thrust bearings; mine had very little out of the box.

Main Frame

Gone are the complicated four piece inner and outer stacked frames of the V1 and V2 T-Rex 450 SE. The 450 Pro (basically the V3 SE model) takes design cues from its bigger siblings. Like the T-Rex 500, 600 and 700, the T-Rex 450 Pro only uses two pieces of carbon fiber, stacked vertically. A new servo arrangement for Align incorporates the bearing blocks for the main shaft with the servo mounts. Interestingly, this new servo mounting arrangement has to be unmounted from the pre-assembled main frame to install the servos. Access to the center cyclic servo (sometimes referred to as the elevator servo) is poor at best, even with the mounts out of the helicopter. I would highly recommend using new screws each time you access the elevator servo, otherwise you risk stripping them. A 1.5 mm ball driver is also a good idea for this tight spot if you can track one down. Mounting the tail servo begs the same question; why bother to have the parts pre-assembled when they have to be taken apart again for the radio gear to be installed? A nice location is provided for a gyro right behind the anti rotation guide, but a location for the receiver is not clearly identified. Receiver location will be further discussed in setup, which will come in the next part of this review, along with the flying portion.

The  pre-painted fiberglass canopy is retained by a small plastic clip on the bottom of the frame, and two aluminum canopy mounts with grommets at the top of the frame. One piece landing gear and a simple two screw holding arrangement help keep the all up weight down. The motor mount is simple with two slots for the mounting screws, although the access to the mounting screws is also a little indirect here as well. It would require removing the two front cyclic servos to have direct access. A diagram is shown in the manual indicating gear mesh, but this view is not visible in the helicopter to set the mesh without removing the two front cyclic servos. The order of construction, and even the other diagram on the same page (page 15) show the cyclic servos installed first. In addition, removing the front cyclic servos would also require removing the battery tray.

Tail Assembly

Align prepares the tail section for you, and its one of the better tails you will find on a 450. Although I question the amount of throw the tail has to oppose torque, I am going to wait to see how it flies before  I criticize it. I am a hard right piro flier, which goes against the torque and is hard on tails, so I’m curious to see how well it works. Counter balanced black anodized machined aluminum tail blade grips should make the tail exceptionally smooth and crisp; they contain two ball bearings each, but no thrust bearing. The single point tail pitch slider seems to have very little slop, and features bushing supported double links to the tail blade grips to free up tail movement. A small amount of slop was noticable on my model in between the machined aluminum tail case and the plastic tail gear. Low profile carbon fiber tail fins are included as well as a machined aluminum horizontal fin/boom support mount. Unlike every other 450 model Align has ever made, this T-Rex features a torque tube tail drive system with bevel gears at both ends (Align calls these “umbrella gears”). Some early versions came with a carbon torque tube with aluminum fittings, mine came out of the box with a full aluminum torque tube. A center rubber bushing with a ball bearing inside keep the tube running true, and splined connectors plug into the back of the bevel gears. Having a torque tube makes assembly and dis-assembly easier than with a belt drive, and performance should be great, but torque tubes are more susceptible to damage than a belt drive.

SPECIAL NOTE ON THIS REVIEW

This review was financed by a special friend of BaronsHobbies.com, who will fly the crap out of the helicopter after the review is complete. His one stipulation on the review was the tail boom be a special custom powder coated tail boom he has made to be extra durable and bright orange. The new T-Rex 450 Pro uses the same tail boom as the older models, so we were able to use one of the booms he had already powder coated for an older T-Rex model. I did have to modify the powder coated boom by carefully sanding down the ends to fit into the tail case and boom mount. To the best of my knowledge, these tail booms are not available for purchase anywhere.