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Old 05-20-2010, 03:43 AM   #3
hjns
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Join Date: Dec 2009
Location: Basel
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So you bought a 4G6, now what?

Your 4G6 is a full collective pitch micro helicopter. Therefore, mechanical setup of the 4G6 requires knowledge of collective pitch helicopters. So start studying first, and make sure that you know what you are talking about!

Homework

Setting up your 4G6 correctly
This may take several hours the first time. So make sure to have enough Lipos available, and only start out with the right tools, or you may break some fragile parts....Find the exploded diagram also on Walkera's website. Below is an expanded version of the original post by Gadflyii.

The following setup was done with the 4G6S (with the 3-axis gyro), the 2801 Pro v2.2 TX, full plastic swashplate, plastic head, CNC blade grips, and Gaui mixer arms. However, the principles should be similar for other variants.
  • Preparations: Remove the landing skids and set the chassis on blocks. I took some LEGO from my kids and used that to stabilize the chassis. Make sure that it is level.
  • Motor setup: the pinion gear should be in “loose” contact with the main gear. Leave just a little bit of room between the two gears, so that the main gear has a very little bit of play. Too tight, and your motor will bog down very easily. Too much play, and the pinion gear will damage the tips of the teeth of the main gear. See also this post by Mikeinde.
  • Remove the head and the swashplate, and all linkages. Remove the servo horns. Disconnect the motor from the ESC.
  • Bind your Transmitter (TX) to the heli. Let it initialize until you hear the high-high-low beeps, and then put the TX into “Idle 1” mode. Then put the throttle in midposition. This will place the servos in midposition as well.
  • Put the servo horns back at 90 degrees. If it is not possible to put them back at 90 degrees, use the subtrim function of the TX to make it better. (True 90 degrees may be inbetween the grooves on the servo throw arms)
  • Turn the heli off. Reassemble the swashplate and the head. Do not add the linkages yet.
  • Position the swashplate along the main shaft in such a way that the swhasplate has equal room to move up and downwards. The swashplate should be directly in the middle between the head above and the collar below. I used my own swash leveling tool (created from a damaged main gear) to do this.
    In the picture here, the red arrows show wrong (unequal) distance of the swashplate to the head-collar, and the green arrows show approximately correct distances. As mentioned above, I used a damaged main gear to position the swashplate correctly.
  • Bind your Transmitter (TX) to the heli again. Let it initialize until you hear the high-high-low beeps, and then put the TX into “Idle 1” mode. Then put the throttle in midposition. This will place the servos in midposition as well.
  • Take one servo-swashplate linkage, and adjust it to the length necessary to place the swashplate in the correct mid-position as described above. Turn the heli off.
  • Adjust the other two linkages from the servo horns to the swashplate so that they are of equal length as the one you just adjusted.
  • Reposition the linkages to the servo horns and to the swashplate. (See image) Note that the rings of the linkages have an inside and an outside. Make sure that the servo horn balls and the swashplate balls enter the rings of the linkages from the inside.
  • Reposition the head, the flybar-ball, and the flybar.
  • Bind your Transmitter (TX) to the heli again. Let it initialize until you hear the high-high-low beeps, and then put the TX into “Idle 1” mode. Then put the throttle in midposition. This will place the servos in midposition and now your swashplate should be level as well. If not, readjust the linkages by 1 linkage and 1 turn at a time to level your swashplate.
  • Add the linkages from the swashplate to the flybar-ball links. The flybar-ball should be positioned in the middle of the head, with ample (preferably equal) room below and above (see image). Turn the heli off.
  • Complete the head with the rest of the flybar, mixer arms, blade grips, and main rotor blades. Make sure that the flybar paddles are level with the flybar-ball links.
  • Bind your Transmitter (TX) to the heli again. Let it initialize until you hear the high-high-low beeps, and then put the TX into “Idle 1” mode. Then put the throttle in midposition. This will place the servos in midposition, your swashplate should be level, the links to the flybar ball are horizontal, and then look at the pitch of the blades. These should be zero (i.e., angle of attack is completely horizontally). If not, adjust the long interlinks from the swashplate to the mixer arms so that both blades are completely level.
  • Tail setup: Loosen the two screws that hold the tail servo in place, and removed the servo horn. Set all sub trims for the tail to zero, and verify there is no trim on the tail servo. Power up the heli and let the servos initialize, then power the heli back off. Put the servo throw arm back on at 90'. Set the tail blade pitch to 0' by hand. Note how far the servo is from the servo rod. Move the servo forward (towards tail) about .5mm and then adjust the servo control rod. Reassemble and powered back on, and verify that the tail is at 0' pitch and servo arm is at 90'.
  • For tail setup, see also the explanation from IMHO.

An even better manual for setting up your swashplate right can be bought here.
It is not expensive for a very good piece of advice!

Balance your blades
: follows.

Different blades. Steve Joblin did a good job and provided a description of the different blades for the 4G6.




Troubleshooting
  • Spinning tail - see the spinning tail troubleshooting guide here.
  • Teethless front tail transmission gear - if you crash on your tail, the main gear may break the teeth of your front tail transmission gear. Either you buy yourself the full cnc front tail transmission gear from Wolfgang, or you create a tail clutch. Quite some mods are available, but you may want to look here first.
__________________
KR, Henk

Blade MCX, FBL 4G6V-2S Xtreme, FBL 4G6V-1S
Xtreme rewind, FBL 4G6S-1S Bell 222 Darthdark, FBL V120D02S

Last edited by hjns; 08-26-2010 at 06:16 AM..
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