Not wanting to hijack your thread here, but I hope this info helps.
A flat (all props/motors on same plane) Hexa or Quad will fall out of the sky using all but a few flight controllers, the Naza not being one of them. several savvy folks have already proven that a broken prop will take even those out. A Y6 or X8 (Equal amount of props on two different planes, upper and lower coaxial) can keep flying in most cases. Again, unless it's a broken prop. So while in concept, you are right, in real world application it's not.
With 4S on these 10" props, you would be over amp'ing the stock DJI motors and thus shortening their life and drastically increasing the possibility of in-flight motor failure. I'm not saying this as a maybe with the stock DJI motors and 10in props on 4S, I am saying it's definitely over-amping them. I tested this setup for someone in person and it was way over the rating for that motor. My suggestion is to always use a Watts-Up meter and verify the actual current/draw/etc on your setup. If you don't have one, be sure to get one. They're invaluable and very convenient since they just go inline between your battery and power dist/ESC's. Also, check your motor temp the next time you fly.
Actually, it's just the opposite. Larger props on 3S battery and smaller props on 4S battery is correct. Larger prop setups will give you a bit more stability, but when the wind picks up, the disc loading will make it more susceptible to the wind changes, and therefore intorduce more tilting and reaction to gusts. Smaller props will offer a little less stability "feeling" and feel lightly mushy. But, they offer slightly better penetration in fast forward flight. So it's a give and take to whatever you are looking to do with your ship.
Other than that, good info here for some folks that may be just starting out. If you are ok with it, I'd like to add a few based on some of the questions and answers so far.
1. When soldering, use a 60/40 rosin core solder. 0.32" diameter standard. Also, use flux paste on all the solder points. You'll apply it with a small brush. I won't go in depth with the explanation, but use it once and you will never solder anything again without it.
There are videos on youtube that explain the proper way to use solder flux paste.
2. Search for a user "wdelarme" on RCgroups. He sells a replacment DJI GPS mount that is the best I have seen and completely affordable (pic below). I fly FPV, so I shield mine with copper tape and a ground drain.
3. If you have a shake or wobble, balance your props and make sure there is nothing loose and rattling against the flight control board or the frame that may transfer vibrations. Get a prop balancer. To add weight, some people use tape. I disagree as it slighly interrupts the airfoil of the prop and can still result in wobble causing behavior. Instead, add your prop balance weight by brushing on a very small amount of some Nutra Nail Bullet-Proof Strength Kevlar Fiber Formula. You can find it online or in some drug stores.
4. When using your ship for FPV, always use a seperate battery for your video downlink. Never use a tap to the main flight battery. If you are powering anything additional form the flight battery, use a good voltage regulator set to the proper voltage.
5. GoPro cameras generate a lot of noise. This tends to interfere with the GPS of your flight controller as well as your OSD GPS if you use one. A good solution for this is to first encase or cover your GoPro in something as simple as Aluminum foil. Yes, the same stuff you wrap leftovers in. ;D You can also use Kapton tape, or even better, adhesive backed copper tape. Copper tape that is used in Electric Guitar shielding is ideal and very inexpensive. An additional step you can take is building a homemade "Groundplane shield". These can be made for very low cost and are super effective.
6. Center of Gravity, or CG Location on your Multirotor is more important than you may think. There are many articles online on string balancing and tuning, CG for multirotors, etc. I use some of them depending on the situation. But I have my own way that's proven to be pretty solid and that is via temperature differences in the motors after a test run. Here's a quick overview of a Hexa in "X" config (For Hexa "Plus" mode the comparisons are slightly different, but very obvious). You will need a temperature gun. Start by taking your props off. Draw the same number of circles on a sheet of paper that are on your ship. In this instance, a Hexa, draw 6 circles in the rough shape of a Hexa. Draw a line cutting the circles one at a time in half. Now arm your multirotor and run the motors up to half throttle for about 30 seconds. Disarm your ship and unplug the power. Quickly take the temp of all of your motors one at a time and write them in the corresponding top half of the circle on your sheet of paper as the motor you took the temp from on your actual ship. You may have to do 3 motors, then wait for them to cool, then do 3 more. If you notice a huge variance in the temperatures from one circle/motor to another, repeat the whole process starting with the opposite motors as the first run and see if you get the same temperatures. Ok, all of that will give you a differential to use as your baseline. So, now put your props on, grab your temp gun, make sure you are outside, power up, and arm your ship. Perform a test hover (not flight, it's important that this is just a hover) for about 2 minutes. Land and DISARM the ship. Now record the temperature after run in the bottom half of those same corresponding circles on your sheet of paper. Now compare your after test flight temperatures of say your back half motors against the front half, or your left half motors against your right half motors. Note that there will be slight differences as you noted earlier in your run up without props on the motors. That was the differential I referenced earlier. Ok, so now you have a better picture of the balance of your ship based strictly off of temperature of the motors. So if one half of your motors run several degrees hotter after your test hover, then try moving some of your gear/electronics/etc slightly toward the opposite, or "cool" side and repeat your test hover until you get the temperatures about equal + or - your variances.
7. Heat Shrink! Buy a bunch of it and use it. Example: When configuring a multirotor and you get the motors spinning the right direction, take the bullet connectors loose one at a time and slip another piece of heat shrink over them. Reconnect the bullet and then shrink the heat tube down to hold those connectors in place. They wont come apart, but are still easy to get apart if you need to. By the way, you can probably guess why I started doing this. Also, I have gotten more thank you messages for this tip than any other.
If you get some time you may want to give a post I made a read. I had a lot of folks PM'ing me on several other forums asking questions like these, so I created a "recipe" of sorts with hints and tips. It also includes an equipment list for successful FPV setup. It's posted here http://m.rc.runryder.com/helicopter/t709427p1/ as well as some other forums. You can just google search "Multi-purpose Hexa Recipe".
It looks like you are having a great time with your Hexa though and learning a lot on the way. Glad you're seeing some success and hope you have much, much more!
View attachment 8227
A flat (all props/motors on same plane) Hexa or Quad will fall out of the sky using all but a few flight controllers, the Naza not being one of them. several savvy folks have already proven that a broken prop will take even those out. A Y6 or X8 (Equal amount of props on two different planes, upper and lower coaxial) can keep flying in most cases. Again, unless it's a broken prop. So while in concept, you are right, in real world application it's not.
With 4S on these 10" props, you would be over amp'ing the stock DJI motors and thus shortening their life and drastically increasing the possibility of in-flight motor failure. I'm not saying this as a maybe with the stock DJI motors and 10in props on 4S, I am saying it's definitely over-amping them. I tested this setup for someone in person and it was way over the rating for that motor. My suggestion is to always use a Watts-Up meter and verify the actual current/draw/etc on your setup. If you don't have one, be sure to get one. They're invaluable and very convenient since they just go inline between your battery and power dist/ESC's. Also, check your motor temp the next time you fly.
Actually, it's just the opposite. Larger props on 3S battery and smaller props on 4S battery is correct. Larger prop setups will give you a bit more stability, but when the wind picks up, the disc loading will make it more susceptible to the wind changes, and therefore intorduce more tilting and reaction to gusts. Smaller props will offer a little less stability "feeling" and feel lightly mushy. But, they offer slightly better penetration in fast forward flight. So it's a give and take to whatever you are looking to do with your ship.
Other than that, good info here for some folks that may be just starting out. If you are ok with it, I'd like to add a few based on some of the questions and answers so far.
1. When soldering, use a 60/40 rosin core solder. 0.32" diameter standard. Also, use flux paste on all the solder points. You'll apply it with a small brush. I won't go in depth with the explanation, but use it once and you will never solder anything again without it.
There are videos on youtube that explain the proper way to use solder flux paste.2. Search for a user "wdelarme" on RCgroups. He sells a replacment DJI GPS mount that is the best I have seen and completely affordable (pic below). I fly FPV, so I shield mine with copper tape and a ground drain.
3. If you have a shake or wobble, balance your props and make sure there is nothing loose and rattling against the flight control board or the frame that may transfer vibrations. Get a prop balancer. To add weight, some people use tape. I disagree as it slighly interrupts the airfoil of the prop and can still result in wobble causing behavior. Instead, add your prop balance weight by brushing on a very small amount of some Nutra Nail Bullet-Proof Strength Kevlar Fiber Formula. You can find it online or in some drug stores.
4. When using your ship for FPV, always use a seperate battery for your video downlink. Never use a tap to the main flight battery. If you are powering anything additional form the flight battery, use a good voltage regulator set to the proper voltage.
5. GoPro cameras generate a lot of noise. This tends to interfere with the GPS of your flight controller as well as your OSD GPS if you use one. A good solution for this is to first encase or cover your GoPro in something as simple as Aluminum foil. Yes, the same stuff you wrap leftovers in. ;D You can also use Kapton tape, or even better, adhesive backed copper tape. Copper tape that is used in Electric Guitar shielding is ideal and very inexpensive. An additional step you can take is building a homemade "Groundplane shield". These can be made for very low cost and are super effective.
6. Center of Gravity, or CG Location on your Multirotor is more important than you may think. There are many articles online on string balancing and tuning, CG for multirotors, etc. I use some of them depending on the situation. But I have my own way that's proven to be pretty solid and that is via temperature differences in the motors after a test run. Here's a quick overview of a Hexa in "X" config (For Hexa "Plus" mode the comparisons are slightly different, but very obvious). You will need a temperature gun. Start by taking your props off. Draw the same number of circles on a sheet of paper that are on your ship. In this instance, a Hexa, draw 6 circles in the rough shape of a Hexa. Draw a line cutting the circles one at a time in half. Now arm your multirotor and run the motors up to half throttle for about 30 seconds. Disarm your ship and unplug the power. Quickly take the temp of all of your motors one at a time and write them in the corresponding top half of the circle on your sheet of paper as the motor you took the temp from on your actual ship. You may have to do 3 motors, then wait for them to cool, then do 3 more. If you notice a huge variance in the temperatures from one circle/motor to another, repeat the whole process starting with the opposite motors as the first run and see if you get the same temperatures. Ok, all of that will give you a differential to use as your baseline. So, now put your props on, grab your temp gun, make sure you are outside, power up, and arm your ship. Perform a test hover (not flight, it's important that this is just a hover) for about 2 minutes. Land and DISARM the ship. Now record the temperature after run in the bottom half of those same corresponding circles on your sheet of paper. Now compare your after test flight temperatures of say your back half motors against the front half, or your left half motors against your right half motors. Note that there will be slight differences as you noted earlier in your run up without props on the motors. That was the differential I referenced earlier. Ok, so now you have a better picture of the balance of your ship based strictly off of temperature of the motors. So if one half of your motors run several degrees hotter after your test hover, then try moving some of your gear/electronics/etc slightly toward the opposite, or "cool" side and repeat your test hover until you get the temperatures about equal + or - your variances.
7. Heat Shrink! Buy a bunch of it and use it. Example: When configuring a multirotor and you get the motors spinning the right direction, take the bullet connectors loose one at a time and slip another piece of heat shrink over them. Reconnect the bullet and then shrink the heat tube down to hold those connectors in place. They wont come apart, but are still easy to get apart if you need to. By the way, you can probably guess why I started doing this. Also, I have gotten more thank you messages for this tip than any other.
If you get some time you may want to give a post I made a read. I had a lot of folks PM'ing me on several other forums asking questions like these, so I created a "recipe" of sorts with hints and tips. It also includes an equipment list for successful FPV setup. It's posted here http://m.rc.runryder.com/helicopter/t709427p1/ as well as some other forums. You can just google search "Multi-purpose Hexa Recipe".
It looks like you are having a great time with your Hexa though and learning a lot on the way. Glad you're seeing some success and hope you have much, much more!
View attachment 8227
Attachments
Last edited by a moderator:
