New Products Flash Sale
Thread Tools
This thread is privately moderated by Steph280, who may elect to delete unwanted replies.
Old Nov 15, 2012, 01:36 PM
Steph280 is offline
Find More Posts by Steph280
1.21 Gigawatts!
Steph280's Avatar
Irvine, CA, USA
Joined Oct 2000
7,594 Posts
Align T-Rex 550E DFC Review

Name: IMG_0407 (1024x768).jpg
Views: 2046
Size: 69.6 KB
Description: Not only is T-Rex 550 one of the best T-Rex, now it is also one of the most beautiful!

The T-Rex 550E DFC is Alignís latest edition of its very successful 550 series of electric helicopters. When I learned about the availability of these kits, I knew I had to add one to my fleet, as the previous T-Rex 550 was already one of my favorite. I had high expectations on what Align did to improve upon an already excellent design, and the new features certainly did not disappoint:
  • DFC flybarless head with matching DFC swashplate. DFC (Direct Flight Control) system is a design which streamlines the rotor head assembly by eliminating the washout mixer, allowing blade grips to connect directly to swashplate. This allows for a lower head that is not only aerodynamically efficient, but also brings the head closer to helicopterís lateral CG line. The DFC system results in noticeably faster forward flight, as well as quicker control response, yet is supposed to reduce energy consumption at the same time.
  • The frame is constructed with 2mm thick 3K carbon plates, along with CNC metal reinforcement plate and mounting blocks. Together these pieces form an extremely rigid, yet light weight frame system.
  • The new 550E DFC kits now come standard with T-Rex 600 tailboom and torque tube drive train. This allows the use of 600mm blades on this helicopter without interfering with tail blades. The included stock carbon blade is 520mm.
  • Tail control is through a 5mm carbon tail pushrod with metal tail control arm, and a precision CNC dual pivot tail pitch slider assembly. This assembly alone contains 6 ball bearings to ensure excellent precision.
  • The T-Rex 550E DFC comes with module 1, CNC machined 112 tooth helical main gear, and a 11 tooth matching steel helical pinion gear.
  • Rudder servo is mounted in between frame for protection, and to bring lateral CG closer to center line.
  • Brand new Align DS615 swashplate digital metal gear servos, as well as Align DS655 rudder digital metal gear servos.
  • Brand new 600MX brushless motor with 1220KV, with heat sink can and built in cooling fan
  • New Castle Creations Talon 90 brushless ESC, 6S 90amps max, BEC 9A continuous with 20A burst, BEC adjustable output 6V-8V
  • New, larger, airbrushed fiberglass aerodynamic canopy
  • The kit arrived in the typical Align boxes within box packaging, neatly labeled with its contents. All the individual pieces are logically grouped together per the building steps to eliminate any confusion.
Name: IMG_0362 (1024x768).jpg
Views: 471
Size: 101.9 KB
Description: Colorful BoxName: IMG_0363 (1024x768).jpg
Views: 440
Size: 74.5 KB
Description: Clean and organized packagingName: IMG_0364 (1024x768).jpg
Views: 792
Size: 101.2 KB
Description: All the pieces laid out.

Construction sequence begins with rotor head, with most pieces already dry-assembled for quick re-assembly (remember to use Loctite/threadlocker). The main blade grips are the typical dual radial bearings type, with thrust bearing for lateral support on the 6mm spindle shaft. Head dampener is of the hard type, as required by the lower DFC rotor head design. The swashplate is a DFC specific design where the balls in upper piece are oriented perpendicular to the center. Most of the pieces here are taken directly from T-Rex 600E DFC, and are labeled as such. Note the direction of main shaft during assembly, with tapered end going down into the main gear.
Name: IMG_0367 (1024x768).jpg
Views: 635
Size: 145.0 KB
Description: Dry Assembled HeadName: IMG_0368 (1024x768).jpg
Views: 731
Size: 75.5 KB
Description: Don't forget to disassemble and apply Loctite to all screws, and pack thrust bearing with greaseName: IMG_0369 (1024x768).jpg
Views: 674
Size: 151.4 KB
Description: Assembled HeadName: IMG_0370 (768x1024).jpg
Views: 636
Size: 108.0 KB
Description: Most head pieces are taken directly from T-Rex 600Name: IMG_0371 (1024x768).jpg
Views: 676
Size: 136.1 KB
Description: Assembled head assembly.

The frame assembly is done by attaching 6 CNC metal blocks holding the 2mm thick carbon side plates to the bottom plate. Together with CNC aluminum bearing blocks and motor mount, the finished frame is very rigid, capable of withstanding some extreme forces. Care should be taken when tightening up the frame mounting bolts; place the assembly on glass surface per instruction to ensure plumpness of the finished assembly.
Name: IMG_0373 (1024x768).jpg
Views: 616
Size: 59.9 KB
Description: 2mm thick carbon plate for frameName: IMG_0374 (1024x768).jpg
Views: 651
Size: 155.3 KB
Description: frame piecesName: IMG_0375 (1024x768).jpg
Views: 613
Size: 107.0 KB
Description: 6 mounting blocks attached to base plateName: IMG_0376 (768x1024).jpg
Views: 722
Size: 80.6 KB
Description: Loosely assemble the frame on glass surface to ensure everything is straight, before tightening it down

The DS615 and DS655 servos in the super combo kit are updated version of the proven DS610 and DS 650. The DS615 cyclic servos are rated at 12.8 kg/cm torque, and 0.07 sec/60į when powered with 6 volts source. The DS655 rudder servos are 5.5 kg/cm and 0.05 sec/60į, also at 6 volts. Both models are digital driven, with coreless motors transferring power through their metal gear transmission. On the test bench, both types of servos seem quieter and less chattery than their predecessors.
Name: IMG_0377 (768x1024).jpg
Views: 653
Size: 148.2 KB
Description: New DS615 cyclic and DS655 rudder servos.  All are digital, metal gear.Name: IMG_0378 (1024x768).jpg
Views: 624
Size: 95.9 KB
Description: Aluminum casingName: IMG_0380 (1024x768).jpg
Views: 783
Size: 141.1 KB
Description: Servos mounted into frameName: IMG_0381 (768x1024).jpg
Views: 867
Size: 102.4 KB
Description: Rudder servo sits on its own mount inbetween frame

With the servos mounted into the frame, now we move onto tail assembly. The dual-pivot tail pitch control assembly is extremely smooth; care should be taken when applying Loctite to the screws to ensure the smoothness is maintained. Should there be any type of binding, remove screws from one pivot point at a time to pinpoint the rough spots. Time spent here will be rewarded with a solid rudder control in flight, and should not be skimped.
Name: IMG_0385 (1024x768).jpg
Views: 816
Size: 95.3 KB
Description: Precision dual pivot tail pitch assemblyName: IMG_0386 (1024x768).jpg
Views: 814
Size: 92.2 KB
Description: Remember to apply loctite to each and every single screws

The 600 size tailboom is a welcome feature to the 550. Longer tailboom not only allows for the option of longer blades, it also provides more leverage for the tail assembly to increase tail control authority and stability. Follow the instruction and carefully glue the bearing to torque tube, lube it up and install in tailboom using the supplied installation tube.
Name: IMG_0387 (1024x768).jpg
Views: 773
Size: 173.0 KB
Description: The clear plastic tube is a handy tool for pushing the torque tube space into the tailboomName: IMG_0388 (1024x768).jpg
Views: 754
Size: 101.5 KB
Description: Assembled tail

The helical main gear rides on a new and improved one way bearing hub assembly. This is similar design to most other modern T-Rexes and has proven to be extremely reliable. The gear itself is very high quality, with perfectly machined mod 1 tooth and clean finish. No noticeable warp was observed on the gear, a typical benefit of machined gear over molded one.
Name: IMG_0391 (1024x768).jpg
Views: 658
Size: 57.4 KB
Description: top: 112T helical main gearName: IMG_0392 (1024x768).jpg
Views: 663
Size: 289.7 KB
Description: bottom: 131T tail drive gear

Name: IMG_0393 (768x1024).jpg
Views: 839
Size: 98.4 KB
Description: Assembled HeadName: IMG_0394 (768x1024).jpg
Views: 908
Size: 109.8 KB
Description: Assembled FrameName: IMG_0395 (768x1024).jpg
Views: 884
Size: 130.2 KB
Description: Complete View

The power system consist of Alignís new 660MX brushless outrunner motor, with a 6s friendly rotation/voltage value of 1220kv. The motorís ribbed casing acts as cooling fins, while the top of the motor has integrated fan to provide active cooling. Also included in the super combo kit is the brand new Talon 90 amps ESC from Castle Creations. While lacking the data recording capability of ICE series, it has a beefy BEC thatís capable of 20 amps peak current, strong enough to handle even the most demanding digital servos. An ingenious mounting system provides a base for the ESC to latch on to, allowing for quick release should you want to swap this ESC between models. Software seems similar as the other Castle ESCís, with similar features such as direct entry government mode, as well as standard throttle modes. Together they form a very potent power system for the T-Rex 550E DFC.
Name: IMG_0396 (768x1024).jpg
Views: 837
Size: 131.2 KB
Description: The power systemName: IMG_0397 (1024x768).jpg
Views: 843
Size: 103.9 KB
Description: Name: IMG_0398 (768x1024).jpg
Views: 830
Size: 70.0 KB
Description: Name: IMG_0399 (768x1024).jpg
Views: 940
Size: 96.0 KB

If there is one thing I had to pick on the original T-Rex 550, Iíd have to say the shape of its canopy. Fortunately the new T-Rex 550E DFC comes with a totally redesigned canopy with a brand new color scheme. The canopy is longer and larger than its predecessor, making the 550E DFC look bigger and more streamlined. The airbrushing graphics are typical of Alignís high quality canopies, beautiful lines with vivid colors. Mounting is done with a lower latch that attaches to the front landing bow, and two rudder padded holes for the rear mounting ears.
Name: IMG_0400 (1024x768).jpg
Views: 858
Size: 71.9 KB
Description: Name: IMG_0401 (768x1024).jpg
Views: 777
Size: 55.4 KB
Description: Canopy LatchName: IMG_0402 (768x1024).jpg
Views: 769
Size: 46.3 KB


With all servos connected to the Align 3GX flybarless system, a single servo wire was used to connect it to the Futaba S-Bus receiver for a very clean install. Setting of the 3GX system consists of a few steps done with the 3GX push button and transmitter stick:
  • DIR mode basically bypass the flybarless system, so you can check for proper control direction, cyclic pitch (must be set to 8 degrees), and collective pitch (set to +/- 12 degrees).
  • Set the elevator travel limit and gyro direction
  • Set the aileron travel limit and gyro direction
Then go through the rudder gyro setup which sets the servo type, frame rate, travel limit, reverse, etc. All steps are clearly explained in the manual, and should be followed carefully to ensure proper setup.
I have a habit of flying electric helis only in idle-up 1 mode. So with the Talon ESC set to fixed end points as default, my idle-up 1 throttle curve is 100-85-80-85-100, with a straight pitch curve of 0-25-50-75-100. Normal throttle and pitch curves are 0-25-50-75-100. No surprises here.
At this time the heli is ready and can be flown. Further tuning of the flybarless system can be done with the Flight Mode settings and gain dial, but I left everything default for the maiden flight.

Name: IMG_0405 (1024x768).jpg
Views: 1941
Size: 98.8 KB
Description: Name: IMG_0406 (1024x768).jpg
Views: 1349
Size: 71.9 KB
Description: Ready for FlightName: IMG_0407 (1024x768).jpg
Views: 2046
Size: 69.6 KB
Description: Not only is T-Rex 550 one of the best T-Rex, now it is also one of the most beautiful!Name: IMG_0408 (768x1024).jpg
Views: 1097
Size: 68.3 KB
Description: Streamlined canopy, looks very slippery!

Allow the 3GX system to initialize after power up, which is indicated by a rapid up-down-up motion of the swashplate. Proper initialization is represented with green LED on the 3GX. As I flipped the idle up switch, the Talon ESC smoothly spun up the rotor with its excellent soft start function. As it reaches full speed, a gentle push of collective stick brought the helicopter into a stable hover. As expected, no trim adjustments were needed if 3GX was setup properly. The 550E DFC just sat there in a comfortable hover.

A quick circuit around the field exhibited increased forward flight speed, as expected from the low drag DFC head and improved 600MX motor. The 550E DFC tracked perfectly through the corners, with noticeably higher control precision. Similar to other DFC equipped T-Rex helicopters, the collective and cyclic response are noticeably quicker. Stationary flips and rolls are fast and stable, with no noticeable wobbles. Tic-tocks are crisp and precise. The new 2.1 software in 3GX contains improved pirouetting compensation routine, which results in stable pirouetting maneuvers at all orientations.

As a midsized helicopter, the T-Rex 550E DFC provides the stability of larger helicopters, while maintaining portability and economical operation. These benefits make the 550 class helicopters a top choice for the weekend fliers, as well as a practice machine for the serious competition pilots. With the excellent performance and value of the T-Rex 550E DFC, the competitions have just seen the bar being raised.
Steph280 is offline Find More Posts by Steph280
Reply With Quote
Sign up now
to remove ads between posts
Old Jun 12, 2015, 12:13 PM
Jezzejamez is online now
Find More Posts by Jezzejamez
Registered User
Jezzejamez's Avatar
United States, MI, Commerce Charter Township
Joined Oct 2013
2,734 Posts
I'm not sure if this is the correct place to ask a question.

I'm setting up a 550e and my tail is not getting full throw. I'm using the ar7200bx.. Maybe point me in the best direction.. Thanks
Jezzejamez is online now Find More Posts by Jezzejamez
Reply With Quote

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Sold Align t-rex 550e v2 HeliPro5 Aircraft - Electric - Helis (FS/W) 1 May 13, 2012 08:06 PM
Sold Align T-rex 550E/600 V2 Slash Crazy Aircraft - Electric - Helis (FS/W) 0 May 03, 2012 07:59 PM
Sold Align T-REX 700E V2 3GX Helicopter Kit WITH DFC COMPLETED HEAD NO Electronics helifreak592 Aircraft - Electric - Helis (FS/W) 0 Apr 04, 2012 05:25 PM
Sold New in the Box ALIGN T-REX 550E 550 3GX V2 A&J Aircraft - Electric - Helis (FS/W) 3 Mar 27, 2012 10:12 AM