It's time to install the Tail Boom and the Anti Rotation Bracket, the Tail Boom is secured using eight M2.5X5MM Button Socket Head Machine Screws, four on either side, the positions are shown in my photo and also the drawing in the manual...

The Anti Rotation Bracket is secured with two T2.6X6MM Button Socket Head Self Tapping Screws, one on either side, there are cutouts in the frame sides which help to secure the Anti Rotation Bracket by means of mating molded sections in the A/R Bracket, it's quite effective...

I mounted my Tail Boom first, then aligning the pin on the rear Elevator Link Ball with the slot in the Anti Rotation Bracket, I put the A/R Bracket in position and secured it with the two self tapping screws...

A couple photos...

Ken

Almost done with the airframe... There are just a couple more steps; Installation of the Pinion on the 450MX Motor, installation of the Motor and Battery Mount, then finally the Landing Struts and the Tail Servo Mount, the assembly is wrapped up when I secure the Boom Supports and the Vertical Stabilizer Mount...

I'm going to start with the Motor installation and then the Battery Mount... The Motor is secured with two M2.5X6MM Socket Head Cap Screws and Washers... The Battery Mount is Secured with six T2.6X6mm Button Socket Head Self Tapping Screws...

A couple photos...

Ken

Next up is installation of the motor into the airframe, I've determined that my ESC will be mounted up front in the stock location under the battery mount, so my motor leads need to face forward...

The direction the motor leads should face dictates which mounting holes need to be used to secure the motor... After determining that I placed the Motor in position between the Frame Sides and secured it in place with two M2.5X6 Socket Head Cap Screws and Flat Washers... The motor mounting screws on the Align T-Rex 450 PRO DFC are a little hard to reach, hardened hex wrenches simply cannot start the screws in the motor because of the angle needed to reach them, see photos...

My Du-Bro Metric Ball Wrenches accomplished this easily, after the screws are started I then use the hardened wrenches to tighten them down fully, try to get as much of the tip of the hardened wrench as possible into the socket on the screws to help prevent stripping the head of the screw...

I slipped the motor into the Main Frame through the bottom of the frame, while holding it in position I started one of the mounting screws, I then aligned the other screw hole with the slot in the Motor Mount and started the second motor mounting screw… After adjusting the gear mesh between the Motor Pinion Helical Gear and the Slant Thread Main Drive Gear I used my hardened hex wrench to tighten them down…

A few photos...

Ken

When the fastener is in a hard to reach place or you can't get a straight shot to the head of the fastener you need an alternative for getting the fastener started, I've found nothing works better than ball end type hex wrenches...

Hardened hex wrenches are great for tightening socket head cap screws and other socket head fasteners, I have a set that is very useful for working on R/C vehicles, the end of each wrench has a slot designed for tightening or loosening Ball Links on linkage rods, I wish I could remember where I got them, I need to replace the blade on my 1.5mm wrench, the tips of hardened wrenches will snap off easily if sideways pressure is applied to them...

A couple photos...

Ken

The Battery Mount serves two purposes; it is also the mounting platform for the ESC on the underside... There are a couple different ways to run the wiring, there is space enough at the top and a cut-out on the front lower portion of the Battery Mount for running the battery wires, the battery wires can only be ran out the top if your ESC will fit that way...

Although there are eight holes for screws on the Battery Mount it is only secured with six T2.6X6MM Button Socket Head Self Tapping Screws... Two of the holes on the Battery Mount are not used...

The stock Align RCE-BL35P ESC fits best with the battery leads coming out the front... Possibly by trimming back a small amount of heatshrink tubing covering the motor wire side of the ESC you could install it the other way...

A few photos...

Ken

Almost done with the airframe... Earlier in the build on page 7 the Landing Skids, Skid Mounts and Carbon Bottom Plate were assembled, it's time to mount that assembly to the Main Frame...

There are six Button Socket Head Screws used to secure the Skid Mounts to the Main Frame, two of these screws are longer, they're used for the rearmost holes to attach the Tail Boom Braces...

Loosen the screws fastening the Skids to the Skid Mounts, adjust the fit so the Frame Sides sit within the raised portions on the Landing Skids (see photos)... Once everything is aligned and in place and secure the front two Skid Mounts to the Frame Sides using the four M2.5X5 Socket Button Head Screws...

Next using the two M2.5X8 Socket Button Head Screws secure the two Tail Boom Braces to the rear two Skid Mounts, one on either side...

A few photos...

Ken

In the manual, the Main Blades are mounted next, I'm skipping past mounting them just because it's easier to move the helicopter airframe around on the bench without them...

I need to prepare the Align DS520 Coreless Digital Tail Servo for installation into the airframe... I need to tap one of the holes in the Servo Horn with a 2mm tap, then thread the Link Ball into the Servo Horn and secure it with the 2mm Nut from the backside...

For those wondering how to get the tidy coiled servo leads, just wrap the servo lead around a 3mm CF rod(tail boom brace) tightly together, then slip the rod out of the coiled lead... Easy...

The drawing in the manual is very detailed and actually shows the lettering on the Servo Horn in the section pertaining to the Link Ball installation... Who am I to argue with the manual??? I tapped the hole shown in the drawing with the 2mm tap...

There are very few threads of the Link Ball shank protruding from the rear of the Servo Horn, I want to use some threadlocker on the 2mm Nut that secures the Link Ball, but I don't want to get any of it on the Servo Horn, the method I use is to start the nut on the shank, about 2 turns, then apply the threadlocker, you can see it in the photo, then I tighten the nut...

The Tail Servo is mounted to the Tail Servo Mount with four T2.6X6mm Self Tapping Screws and four Flat Washers...

A couple photos...

Ken

I found it easier to remove the servo horn from the Servo to install the Ball Link of the Linkage Rod onto the Link Ball on the Servo Horn, much easier than wrestling with the Servo, Servo Mount and Linkage Rod...

The easiest way to install Ball Links is with a pair of Ball Link Pliers, mine are old, at least ten years old, I think they're century branded, any helicopter larger than 250 they are almost essential, the great thing is they support the Link Ball from underneath, so no stress is applied to the part... Mine also have two grooves across the jaws for holding linkage rods and other round objects...

For now I'm leaving the Ball Link off of the Link Ball on the Tail Pitch Bellcrank, until I have all of the servos centered to avoid overdriving or stalling any linkages... The Tail Servo Mount is secure to the frame via four T2.6X6MM Socket Button Head Self Tapping Screws, two on either side...

A few photos...

Ken

A tip on the Tail Boom, you may want to drill and pin the boom to the front gearbox. It pulls out pretty easy. You can use the spare servo horn screw from the kit. Tip from Finless Bob...

Originally Posted by ThomasHumble

A tip on the Tail Boom, you may want to drill and pin the boom to the front gearbox. It pulls out pretty easy. You can use the spare servo horn screw from the kit. Tip from Finless Bob...

Thanks for the tip, on my T-Rex 250s, I put a wrap of clear packing tape on the section in the boom mount, one wrap and it stays secure...

I'm just waiting on a couple satellite rxs to arrive, maybe today, then on with the electronics installation...

Ken

My Spektrum DSMX Satellite RXs arrived yesterday... For those following along I will be starting the installation of the electronics, determining the wire routing and Spektrum Satellite RX placement etc...

After installing the radio components I'm going to document the setup of the Align 3GX FBL controller, this is the first Align 3GX I'll be setting up so it should be a learning experience for me and quite entertaining for all of you... More to come...

Ken

Rather than use the ESC/BEC to power up the system during the setup process I use a 6 volt nimh receiver battery, I purchased a good quality one just for this purpose...

Additionally I use a switch harness during the setup that way if there's any problems I can kill the power just by flipping the switch, instead of fumbling with lipo battery connections, doing it this way also minimizes the short circuit risks associated with lipo batteries sitting on a work bench with a bunch of metal tools etc...

Just an idea...

Ken

Thanks for your awsome build thread , will you be posting up your setups when its finalized? keep up the great work! looking forward for more reviews on this kit!

You're all most welcome, I am glad others are following along... Thank you for the kind words, yes, I will be documenting all the details of my setup and any tweaks I make during the first flights...

Thank you all for following along...

Ken

This is an awesome thread. Thanks.

I am starting to build my 450 Pro DFC on Monday so I am looking forward to that.

Set up will be a little different on mine because instead of the 3GX I am using a HC3-SX.