It appears you have the older version of the KK controller, the new blue and black boards come with gyros already mounted though they do cost a wee bit more up front. So let’s see here, frame and controller, yes you'll also need speed controllers, one for each motor and they should at a minimum be rated for the highest current draw of the motors that will be attached to them. Motor specs should have both Standard Current and Max Current capacity listed, the standard being the current draw in normal operation and the max current being the absolute most they can possibly draw.
Typically the ratings look like this Standard Current: 6-17A, Max Current: 22A, so 90 something percent of the time the motor will be in that 6 -17 amp range and you could quite easily get away with running an 18 amp speed controller provided it can withstand a burst current equal or greater to the max current rating of the motor. Typically speed controller ratings look like this, Cont Current: 18A, Burst Current: 22A, so this particular speed controller will work just fine with the above motor and in fact I use both the motor with those specs and the speed controller with these specs on my Hoverfly quad. So make sure the speed controllers you buy are compatible with the motors, check the current ratings on both and make sure they match.
You will also need props, and generally there are two limiting factors, the motors and the size of the frame. You can have a motor capable of turning a larger prop than will fit on the frame and it will work provided the prop isn’t too small and being turned too fast by the motor, going the other way and having a prop that is too big for the power of the motor is going to make for a poor flying multi and could potentially cause the motors and/or speed controllers to run too hot. So how do you know what is the proper size propeller? Most of the better motor manufacturers will tell you what size prop it is capable of turning and you should always follow that guideline. If the motor you’re considering doesn’t list the prop sizes, then note the specs and look at another brand with a motor of similar specs to see what they recommend and use that as a guideline the power of motors doesn’t, or shouldn’t, vary that much between brands for the same specs.
Other things you will need, some “noodle wire” (silca gel covering) for various connections such as battery to power distribution harness or board, connection from the harness/board to the speed controllers and depending on the length of the arms on the frame you may have to stretch the wiring between the speed controller and the motors. You can either hardwire the speed controllers and motors together by soldering the wires or use bullet connectors to make swapping parts easier. If you decide to go the connector route then you need to figure how many and what size and order them as well. I use 3.5mm for main power connections between harness and speed controllers and 2mm between the speed controllers and motors on the smaller quads I build along with 16 gauge wire between the speed controllers and motors and 20 or 22 gauge for battery and power distribution harness depending on how much of what gauge I happen to have hanging around when I’m doing the assembly.
You’ll want to have some degree of protection for the electronics so you can get a bit creative here and use a number of things. I have a preference for Lock and Lock food containers for the little quads and vacuum formed acrylic domes for the bigger quads and hexas. Here are a couple examples of what I’m referring to...
My 350mm KK controller aerobatic quad
The Hoverfly quad with acrylic dome
To finish things off you will need a radio transmitter and receiver. The KK will do just fine with any 4 channel setup you care to use, it’s a very basic setup and only needs throttle plus tilt, roll, and yaw control, that’s it. If you see yourself moving up to bigger multis with more capability and the budget allows, definitely get at least a 7 channel radio to start, there’s a lot of them out there for reasonable prices these days. If you think you may be interested in doing aerial photography and video at some point, more channels are better, I use an 11 channel radio but that’s getting into the expensive end of the price range and probably a lot more than you’ll need for a while.
Hopefully this answers a lot of your questions, you will have more before you’re done!
Ken
