I was asked by a fellow club member to type this up so he has a basic reference on how to setup a new machine. Its not the only way of setting a machine up, but its how ive always set up my machines and has always stood me in good stead and worked well. Feel free to comment if you think ive missed anything or if there are any glaringly obvious mistakes
This guide assumes you know how to read blade pitch and have some basic understanding of a heli and transmitter.
Basic Instructions for mechanically setting up a CCPM Heli
This assumes the heli is built and ready for the electrical setup. On an electric heli, before you start, check your throttle direction to ensure bottom stick is zero throttle. Once that's done, set throttle hold to hold at 0% and disconnect your motor wires while setting the swash up to make sure you don't get any nasty surprises. Also, remember to mirror each change you make to the same linkage the other side of the head as they should always be the same length to ensure your blade tracking is spot on.
1. Assign a new model memory and select a 120 degree swash type (SR-3 on futaba, 3 servo 120 degrees on JR/Spektrum)
2. Bind your TX and RX with throttle hold enabled and collective at mid stick. Push the servo horns on so they are roughly level, just to use as a visual indicator.
3. Move your collective from minimum to maximum and watch the 3 swash servos. They should all move up together as you increase the collective. If they dont, go to the reverse menu and reverse the required servo(s). Now check they all move up when applying positive collective, down for negative.
4. Now the swash moves up and down as it should, check your aileron and elevator directions. The swash plate should tip in the direction you push the cyclic stick. If it doesn't, go in to the swash AFR menu and simply reverse the required element. E.g. If your elevator is reversed, go in to the Swash AFR menu, select ELE and reverse it (so if it says +50 and is moving in the wrong direction, change it to -50).
5. Now make sure your pitch curve is set to the default 0 25 50 75 100, then go to the sub trim menu. Put the collective to mid stick and put all the servo horns on, trying them in as many positions as possible to get them as close to horizontal as possible. If they aren't level, use sub trim on the required channel but use as little as possible. if its more than 20 points, try another servo horn.
6. once your happy they are all level at mid stick, put the servo horn screws in, attach the balls and links and ensure the swash is also level. Adjust each link as required to make the swash level.
7. Now work on the head from the swash up. Each mixing arm should be level while the swash is at mid stick, if they aren't, adjust the required link to make sure it is, always working from the bottom up.
8. Now move the collective up and down watching the washout base (the bit with the mixing arms on above the swash). The washout should have a similar gap to the head and swash when at the extremes of collective. If its not, you will have to adjust the 3 servo to swash linkages. if you have to do this, you will need to also re-adjust the rest of the linkages to make sure the mixing arms are all level again. If you've not got enough swash movement, increase your PIT value in the Swash AFR menu.
9. Now everything is level, all that's left to do is to check and set your blade pitch. With the collective at mid stick, attach your final linkages from the blade grips to the mixing arms, and install your blades. at mid stick your blades should be at 0 degrees. Check this with your pitch gauge and adjust the final link as required. Once you have 0 degrees at mid stick, check your full positive and negative pitch values. They should be equal, if they aren't you probably don't have all your mixing arms level. If your pitch value is too low or high (aim for around 11 or 12 degrees) go back in to your Swash AFR menu and increase/decrease the PIT value and recheck your pitch.
10. Its now worth checking your cyclic pitch. This is the amount of aileron and elevator movement you have. To do this, first of all put your blades in line with the boom and at zero degrees pitch - mid stick. Now put your pitch gauge on the blade at the front of the heli. Check your full aileron pitch by moving the cyclic to full left or right aileron and read the pitch off as you would for the collective pitch. you don't want any more than about 8 degrees really. Check for binding on the swash. If you've got too much or little then go to your Swash AFR menu and increase/decrease the Ail value as required. Now do the same with your elevator, but to do this turn your head so the fly bar is in line with the boom and then repeat the previous.
11. If your linkages are all set correctly, and the servo horns level, you shouldn't have any interaction. To check this, hold one of your fly bar paddles and move the pitch up and down. you shouldn't feel any movement in the paddle, if you do you need to find out which servo is introducing the interaction by watching the swash plate as you move the collective up and down. You should be able to see which side of the swash is moving up too much and down not quite enough. Re-level this servo by adjusting the sub trim for it, then re-level the swash by adjusting the linkage on that servo. Now move the collective up and down again and see if it remains level again. keep adjusting until it is as close to level all the way up and down. Another way to do this is to adjust the end points of the relevant servo, this is however far from ideal. If you do this, you will end up with a heli that climbs straight because there is no interaction, but at the extremes of cyclic travel it will start to roll and flip slightly off centre as the servos will not be travelling as far as each other, so try to avoid doing it this way.
12. Last to do is your tail setup. This is largely dependant on your particular gyro, so ill only detail the mechanical setup. Set the gyro to rate mode as this centres the servo and it wont want to move away from centre. Pop your servo horn on so that the arm you are using is at 90 degrees pointing straight up from the servo. The tail pitch bell crank on the gearbox should generally be square to the boom and gearbox when the servo horn is at 90 degrees as you've just set. Adjust the tail control push rod to make this the case. You should now have an equal movement of the servo horn in both directions, check this with the rudder control. If its not, adjust the push rod as required, then set up your gyro ensuring to set up your travel limits on the gyro.
13. Last but not least, always re-bind your tx and rx now its all setup. You need to bind it with the collective at 0 degrees and the throttle on hold at 0%. This will stop anything too drastic happening if the connection between the tx and rx is lost in flight.
Your heli should now be mechanically setup close to perfect, its just a question of test flying it, you may need a few clicks of trim, but it should be very close. you may want to limit your negative pitch in normal, but personally i run the same pitch in all flight modes - this stops any nasty jumps in height as you change between idle up and normal for instance, but this is personal preference.
This guide assumes you know how to read blade pitch and have some basic understanding of a heli and transmitter.Basic Instructions for mechanically setting up a CCPM Heli
This assumes the heli is built and ready for the electrical setup. On an electric heli, before you start, check your throttle direction to ensure bottom stick is zero throttle. Once that's done, set throttle hold to hold at 0% and disconnect your motor wires while setting the swash up to make sure you don't get any nasty surprises. Also, remember to mirror each change you make to the same linkage the other side of the head as they should always be the same length to ensure your blade tracking is spot on.
1. Assign a new model memory and select a 120 degree swash type (SR-3 on futaba, 3 servo 120 degrees on JR/Spektrum)
2. Bind your TX and RX with throttle hold enabled and collective at mid stick. Push the servo horns on so they are roughly level, just to use as a visual indicator.
3. Move your collective from minimum to maximum and watch the 3 swash servos. They should all move up together as you increase the collective. If they dont, go to the reverse menu and reverse the required servo(s). Now check they all move up when applying positive collective, down for negative.
4. Now the swash moves up and down as it should, check your aileron and elevator directions. The swash plate should tip in the direction you push the cyclic stick. If it doesn't, go in to the swash AFR menu and simply reverse the required element. E.g. If your elevator is reversed, go in to the Swash AFR menu, select ELE and reverse it (so if it says +50 and is moving in the wrong direction, change it to -50).
5. Now make sure your pitch curve is set to the default 0 25 50 75 100, then go to the sub trim menu. Put the collective to mid stick and put all the servo horns on, trying them in as many positions as possible to get them as close to horizontal as possible. If they aren't level, use sub trim on the required channel but use as little as possible. if its more than 20 points, try another servo horn.
6. once your happy they are all level at mid stick, put the servo horn screws in, attach the balls and links and ensure the swash is also level. Adjust each link as required to make the swash level.
7. Now work on the head from the swash up. Each mixing arm should be level while the swash is at mid stick, if they aren't, adjust the required link to make sure it is, always working from the bottom up.
8. Now move the collective up and down watching the washout base (the bit with the mixing arms on above the swash). The washout should have a similar gap to the head and swash when at the extremes of collective. If its not, you will have to adjust the 3 servo to swash linkages. if you have to do this, you will need to also re-adjust the rest of the linkages to make sure the mixing arms are all level again. If you've not got enough swash movement, increase your PIT value in the Swash AFR menu.
9. Now everything is level, all that's left to do is to check and set your blade pitch. With the collective at mid stick, attach your final linkages from the blade grips to the mixing arms, and install your blades. at mid stick your blades should be at 0 degrees. Check this with your pitch gauge and adjust the final link as required. Once you have 0 degrees at mid stick, check your full positive and negative pitch values. They should be equal, if they aren't you probably don't have all your mixing arms level. If your pitch value is too low or high (aim for around 11 or 12 degrees) go back in to your Swash AFR menu and increase/decrease the PIT value and recheck your pitch.
10. Its now worth checking your cyclic pitch. This is the amount of aileron and elevator movement you have. To do this, first of all put your blades in line with the boom and at zero degrees pitch - mid stick. Now put your pitch gauge on the blade at the front of the heli. Check your full aileron pitch by moving the cyclic to full left or right aileron and read the pitch off as you would for the collective pitch. you don't want any more than about 8 degrees really. Check for binding on the swash. If you've got too much or little then go to your Swash AFR menu and increase/decrease the Ail value as required. Now do the same with your elevator, but to do this turn your head so the fly bar is in line with the boom and then repeat the previous.
11. If your linkages are all set correctly, and the servo horns level, you shouldn't have any interaction. To check this, hold one of your fly bar paddles and move the pitch up and down. you shouldn't feel any movement in the paddle, if you do you need to find out which servo is introducing the interaction by watching the swash plate as you move the collective up and down. You should be able to see which side of the swash is moving up too much and down not quite enough. Re-level this servo by adjusting the sub trim for it, then re-level the swash by adjusting the linkage on that servo. Now move the collective up and down again and see if it remains level again. keep adjusting until it is as close to level all the way up and down. Another way to do this is to adjust the end points of the relevant servo, this is however far from ideal. If you do this, you will end up with a heli that climbs straight because there is no interaction, but at the extremes of cyclic travel it will start to roll and flip slightly off centre as the servos will not be travelling as far as each other, so try to avoid doing it this way.
12. Last to do is your tail setup. This is largely dependant on your particular gyro, so ill only detail the mechanical setup. Set the gyro to rate mode as this centres the servo and it wont want to move away from centre. Pop your servo horn on so that the arm you are using is at 90 degrees pointing straight up from the servo. The tail pitch bell crank on the gearbox should generally be square to the boom and gearbox when the servo horn is at 90 degrees as you've just set. Adjust the tail control push rod to make this the case. You should now have an equal movement of the servo horn in both directions, check this with the rudder control. If its not, adjust the push rod as required, then set up your gyro ensuring to set up your travel limits on the gyro.
13. Last but not least, always re-bind your tx and rx now its all setup. You need to bind it with the collective at 0 degrees and the throttle on hold at 0%. This will stop anything too drastic happening if the connection between the tx and rx is lost in flight.
Your heli should now be mechanically setup close to perfect, its just a question of test flying it, you may need a few clicks of trim, but it should be very close. you may want to limit your negative pitch in normal, but personally i run the same pitch in all flight modes - this stops any nasty jumps in height as you change between idle up and normal for instance, but this is personal preference.





Comment