The best method (for me) to build one of these 3d beta boxes is:
1. Solder 16awg red silicon wire into the positive pole of a fdv connector. Leave two inches long (4/5cm) an cut the wire.
2. Solder a 16awg black silicon wire to the fdv ground ring. Leave again 2 inches of wire and cut off the rest.
3. Install the 510 connector and tighten down the nut well. Make sure the black ground wire is on the left side of the connector, near the bottom (farther away from you)
4. Place the lipo (turnigy nano tech 950mah or equivalent) on the back of the board, wires facing down but exiting from the lipo closer to you i.e. You want the wires running along the lipo straight to the board (20mm long) . Not directly from the corner of the lipo to the board. Tape the battery to the board temporarily.
5. Cut each battery wire (4 + 2) separately so that it reaches the board plus 3 or 4mm. Isolate each wire you cut with some painters tape.
6. Start to solder each balance wire straight to the board. Carefully avoiding touching close by lanes or touching other solder joints.
7. Solder positive power wire to the board.
8. Install the oled screen
9. Solder the ground wire. Board is now live! Be double careful. You can now remove the tape that holds the lipo in place.
10. Insert the board diagonally into the enclosure (top part first) and find a way to secure the board temporarily at an angle of 30 degrees or so.
11. Place screen in correct position. Use strong tape (fiberglass reinforced) or even a dab of silicone (I prefer tape) to fixate the screen in final position.
12. Put board in place and tighten down the 3 1.6mm screws. Make sure you listen carefully as you tighten down the lower screw (in the USB area). If you hear a click, then the board is pressing too much against the front wall and is activating one of the two lower buttons. Either sand down the button or back off half a turn.
13. Solder the ground wire from the fdv connector to the top ground tab. Make a 360 loop with the wire before you solder to give you margin of movement if you need to access the screen later.
14. Solder the positive pin fdv connector wire to the out tab. Proceed as previously and make a 360 loop before soldering.
15. Put lipo in place, close the lid and screw it on with 4 2mmx20mm screws.
Enjoy
Regards
Tony
Sent from my keyboard through my phone or something like that.