Hirobo Embla 450E SLM Build
Construction of my Hirobo Embla 450e has finally started. It has been relatively easy with great integration between the packaging of parts and the assembly drawings. Package 1 of parts is completed using assembly drawing 1 etc. The only things I would suggest is installing the tail servo on the bracket before screwing the bracket to the main frame, and perhaps install the motor in the early stages with the frame assembly.
Some headings have missing package numbers, this is due to the Hirobo manual covering SLM and SZM2 construction
Package 1: Main Frame
Nicely cut out and finished off, no sanding required on this one.
Package 2: Skids onto Main Frame
Package 2 contains the skids, receiver trays and the battery tray. These all went in easy with quality allen head screws, rather than phillips head style. I much prefer these as there is less chance of damaging the heads and they have a better feel when screwing in.
Packages 3 & 4: Tail and Rudder Assembly
Package 5: Tail Boom Assembly
Assembling the tail hub is relatively easy with a bit of care required when installing the drive belt. I used a wire coat hangar that had been cut and a small hook bent to pull the drive belt through the tail boom to ensure the correct twist is maintained.
Package 6: Tail Boom Brace Assembly
The instructions do this next. I have left it until I'm ready to install these on the heli, this means I can be absolutely certain that the end terminals are installed with the correct orientation, and not introduce unnecessary stress into the frame.
Package 7: Tail Boom Assembly
Boom assembly onto the main frame is straight forward. A couple of things to take care with are that the boom slot is aligned correctly as it is installed into the main frame and the drive belt is correctly twisted. Once again use of a metal hook as the belt is pulled into the boom prevents to many twists causing binding and possible damage. The next stage is installing the tail rudder rudder servo, I installed the servo into the bracket at this stage prior to installing the bracket onto the heli. This is much easier.
Package 8: Rudder Servo Install
Futaba tail servo installed onto the servo tray.
Package 9 & 10: Elevator Lever and Servo Install
Servo installation was a bit fiddly with 10 thumbs, but is not to difficult. Paying attention to the ball link placement distances is required, I have a cheap vernier for this but a good ruler will suffice.
These are the servos I have.
Packages 13,14 & 15: Yoke, Grips and Wash Out Assembly
Beautifully finished metal work assembled easily. The blade grip bearings and spacers where pre-assembled in the grips. Very little effort and a little bit of lubricant are required to assemble this lot. I have used a bit of loctite on all metal threads, taking care not to put to much on so as to cause binding in non threaded parts. A smear of loctite and gentle wipe with a tissue to remove any excess in my experience makes sure they don't come loose.
Packages 23,25 & 27:Assembly of Head, Washout and Swashplate
Once the swash plate, washout and head are installed ensure the wash out is lined up correctly with the head, the wash out bars are horizontal to the main shaft and the linkage from the swash to the head is in line with the main shaft.
Package 29 & 35: SWM Linkage and Motor, Swash Plate Close Up
Close up of swash plate with linkages mounted. Notice the round linkage from the swash to the head is not in line with the main shaft. This hasn't been aligned yet. It may be easier to mount the motor when assembling the frame in the early stages. The ESC has been relocated from where it is shown here to be mounted from the instructions. It now resides further back to get it into air flow for cooling, see pics below.
Gyro Mounting Plate and EPB
The Bavarian Demon 3SX servo wont fit onto the servo tray because it is a bit to big. I have cut a piece of 1.6mm sheet metal, scuffed the plastic mounting surface and used a good quality metal and plastic glue making sure to only glue the plate to the gyro surface and not to the frame sides. The piece of wire you can see has been soldered to provide Equipotential Bonding (EPB) for the metal plate. This connects to the EPB on the tail boom, motor mount and heli main frame. The EPB is required to protect the BD3SX from voltage spikes that can be generated from the moving parts and electronics.
Bavarian Demon 3SX Mounted on Embla 450E
I have chosen the BD3SX for this build so that I can learn how to set it up and use it before I build my Goblin 630.
The gyro has been mounted using the recommended thin tape. The servos have been temporarily hooked up so that I can just test the basic connection/operation of the gyro. The EPB has been completed and checked.
Close Up of BD3SX
This is the BD3SX after the initial power on test and the wiring has been loomed. You can see the EPB wire coil onto the plate and the boom. I have puchased a Spektrum DX8 and are using 2 x Spectrum DSM2 satelites for the BD3SX, one is visible mounted on the gear tray to the right of the tail servo.
RH View showing BD3SX and Spectrum DSM2 Satellite
LH View showing BD3SX and the ESC
The ESC has been moved further back than was shown in the instructions. This will get it into better air flow and makes the cable path ways a bit neater. You can see the second DSM2 satellite grey wire sticking out just below the tail servo. It is mounted with Velcro on the gear tray.
BD3SX Loom
Here it is basically done. The loom needs a bit of a tidy up but that will come after maiden.
To be Continued
