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Knuckle Quad - Components

#1
I've been flying toy grade Heli's and Quads for a several years and have decided to try building my own quad that can handle the mild wind outdoors better than the Syma X5.

I've decided to start with the Flite Test Knuckle quad as the platform. I want something that will do "ok" at everything rather than be really good at any one thing (e.g. racing, acro, or photography.)

I would like to add my Mobius and my FPV camera (Spektrum Ultra micro) later to get some fun videos and learn FPV but I'm not planning to use this build to be a racer or professional photography rig.

I'm curious what others have used for the Knuckle quad build and what their build is designed for. For example if somebody lists a build and uses it for Acro that would be good for somebody else who wants to find a good Acro build. I don't see any thread where people have shared their build components for this particular quad frame so I'd like to start that and ask for some advice on what I'm thinking of using for my own "all purpose" build.

Option 1:
Turnigy Multistar 2209-980kv outrunners (Hobby King) (I like the zombie Green motor color)
8045 SF Props (Green) (Hobby King)
Afro ESC 12A ultra lite w/SimonK (Hobby King)

Option 2:
Turnigy Park300 1380kv Outrunners (Hobby King) (Flite Test recommends)
8045 SF Props (Hobby King)
Afro ESC 12A ultra lite w/SimonK (Hobby King)

Option 3:
RTF Mini motor 1800kv (Ready to Fly Quads [RTFQ])
8045 SF Props (Hobby King)
F-20A Fire red ESC (RTFQ)

Other info:
a. I plan to use 3 cell battery.
b. I have already purchased the Taranis X9D w/X8R receiver.
c. I want to take advantage of the telemetry to get Battery voltage and RX Signal.
d. I plan on building many more quads, tri's, and hexes/octo's as I progress and learn more. I would like to build a dedicated race quad capable of doing flips and rolls and a dedicated photography tri, hex, or octo later on.


Questions:
Considering my intended use and that this is my first build and although I'm not new to quads I'm not a pro either.
1. Do any of these options stand out as The best or worst option (include recomended mods if needed).
2. I like the look of the green motors in option 1 but I would go with something else if these are not a good option.
3. I'm not sure if the 8x4.5 props are good with the slower 980kv motors in Option 1 or the faster 1800kv motor in Option 3.
4. I'm not sure if the 8x4.5 props are even the right size/pitch for my purpose even if they will work with the motors.


I get the impression that picking a Flight control board is like picking Chevy vs Ford and don't want to start a control board debate, but if anybody has one of these setups or similar and can share some experience or thoughts on a control board that is either really good or really bad for this configuration I'm interested in hearing your thoughts.

I've done programming with a bunch of opensource projects for ~20 years so that concept is of interest to me but I'm also willing to use a closed source controller to start with and go with an opensource controller later when I'm not as much of a noob although I feel like learning one board might be a better long term option.
 
#2
I have a knuckle h quad, Im using the Turnigy park 1380 motors with gemfan 8x4.5 props, but am using 20A simon k escs and a kk2.1.5 board, flies great plenty of power.
 
#3
If Flitetest recommends option 2 I'd just go for that. I think the motor FT recommends will deliver more power than the multistar since the KV is the same but you're using the same prop. I've also heard some people complaining about the quality of the multistar motors.

For the flight controller I would go with the Naze32 for that size of a quad it's probably the best and most popular flight controller. It's cheap, small and you can adjust it however you want. It does require some skill to get it set up and tuned right. But there are tons of tutorials about that.

Good luck.

Micha
 
#4
I have a knuckle h quad, Im using the Turnigy park 1380 motors with gemfan 8x4.5 props, but am using 20A simon k escs and a kk2.1.5 board, flies great plenty of power.
Thanks for the response. My only reason for questioning this was that in one of their other videos they said not to mount the motors on the bottom because it put the blades too close to the arms. Have you noticed any issues with the props being close or did you find some way of mounting the motors differently.
 
#5
If Flitetest recommends option 2 I'd just go for that. I think the motor FT recommends will deliver more power than the multistar since the KV is the same but you're using the same prop. I've also heard some people complaining about the quality of the multistar motors.

For the flight controller I would go with the Naze32 for that size of a quad it's probably the best and most popular flight controller. It's cheap, small and you can adjust it however you want. It does require some skill to get it set up and tuned right. But there are tons of tutorials about that.

Good luck.

Micha
Thanks for the response,
I did order the Naze32 for the same reasons you mentioned. I opted for the "Turnigy Aerodrive SK3 - 2822-1275 Brushless Outrunner Motor" based on a build that I found somebody else did. I'm not sure if they will have the power I need but I'm keeping my fingers crossed.
 
#6
I built a knuckle quad , 370mm , weighs 705 grams without battery. I used the power pack from altitude hobbies which is a suppo 2208/1450 motor(park 370 equivalent), 130 watt motor, 22 amp ESC's, 8x4.5 props. It has plenty of power. Using a 2200mah, 30C, 3s battery I get 8.5 to 10 minutes of flight. Using a 3700mah I get 12 to 13 minutes of flight.

891 grams total weight with 2200mah, 988 grams total with 3700mah.

I have done some other load testing on it, I think around 1000 grams is its weight limit, as in after that amount of weight flight time diminishes drastically. So this will give you some sort of idea of what these motors can carry. NOTE: this does not include any FPV gear, which is coming soon.

Unless you are building a smallish quad that weighs alot less than mine the first 2 motor selections will be under powered I believe, especially if you will be putting on FPV gear.

The 3rd choice you have selected looks to be a powerful motor with a lift capability of 800 grams. These would give you plenty of power to carry your gear. Total lift capability of approx. 3200 grams/2.5 =1280 grams total weight of quad, battery, fpv gear and still have a very good flying machine.

To have a good flying quad you want a minimum of 2.2:1 thrust/weight ratio. Quad size will dictate maximum prop size you can use, total weight of the quad will tell you what size motors you need , IE: total thrust.
 
#9
I mounted my motors with some mounts /legs that I got off ebay that were made to fit the 1/2" booms, the only way to mount them is to mount them low or at the bottom edge of the boom but I have no problem with clearance on the props. With the Turnigy park 300 1380kv motors I have plenty of power but im not using any fpv gear at the moment. It climbs like a rocket though so im sure it could carry more weight without too much trouble, i cant speculate on how muchflight time I would lose. I have been having a blast flying it though. I tried a flip the other day for the first time and pile drived it into the ground. Frame held up great. Motor mounts broke but easily glued back together and flew again same day. Need to do some stick scaling before i try that agin. Lol
 
#10
I'm glad your enjoying it and its working good with those motors. If the ones I ordered don't work out at least I know I can go to those. Hopefully by the time I'm ready to try a flip somebody else will have posted good PID settings for this or a similar configuration.
 
#11
This is my first post and could use some help with the motors and props. I read this thread before purchasing motors and props. I have Turnigy 1380 Park 300 motors and 845 props. I can't figure out how to mount the props. The motor shaft is long and there is a collet type fitting but the prop doesn't center on the shaft. Is the metal sleeve supposed to fit in the big hole side of the prop? Thanks for any help!
 
#12
First off, the prop saver screws need to come out. I had to change the motor shaft so it comes out the other end of the motor from how they come from hobbyking. To do this is a bit tricky. First off check if there is grub screw that needs to be loosened or removed that holds the motor shaft. Also there is an e clip that needs to be moved from its current slot in the motor shaft which is right up against the motor bell, to the slot in the end of the shaft. When doing that step make sure not to loose the brass shim that is between the endbell and the e clip. Use a small socket over the short end of the shaft as a spacer. Once that is complete I used a vice as a press. Slowly tighten down the vice until the shaft presses through and stop just before the e clip bottoms out against the end bell. It sounds a little complex but its really not. I did break one of my motors the first time I tried it but thats because i used a socket that was too big. You want one that is larger than the shaft but it needs to be right up against the bearing. Maybe there is a better way if someone else knows please chime in.
 
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#13
Thanks for the info but I still don't see how the prop gets mounted to the motor shaft.... Haven't found any videos on it yet so I must really be overlooking something...
So if I get the motor shaft sticking out the other side, then what? I do real good with pictures ;)
Thanks....
 
#14
Ok...so today I went to an RC hobby store about 20 miles away. Great store with lots of stuff. I'm a newb's newb so if anyone else new to this, hopefully you will not make the same mistake. I ordered 8X4.5 props online and duhh...I didn't know there is a difference between airplane props and props I'd need for the Turnigy1380 motor. So I had to buy the correct props. The airplane props are a lot more sturdy and I'd like to make them work but I'll save that for some other time.

Thanks to coppercanyon I was able to push the shaft out the other end of the motor. Used a 7/32 socket and it worked great. That sucker is tight. It creaked and popped all the way. I damaged the eclip and will have to get another one. There are two brass washer/bushings under the eclip. I know because I dropped one of them when I was working with the clip and it hit the floor. Took a long time to find it. I put a dab of blue thread locker on the prop saver screws that were against the shaft. I hope that is strong enough.

Last, does anyone know the thread size of the mounting holes on this motor? I'm going to need longer screws.
Thanks...
 
#15
Mine were tight also. I took the prop saver screws out and left them out. Didn't your motors come with the collet style prop adapters? That is what I mounted my props with.