Build a Tri-Copter

[Neons]

Building a Tricopter can be done with all parts purchased for maybe an average of $130 ready to fly if you have a receiver and a battery or two. Actually cheaper than the Quad multi. 1 less motor and Esc needed. You can make your own frame as seen in this video and maybe save $20 over a manufactured frame and it will be just as good. You will be surprised how easy it is to have your own Tri with little work. A piece of 1/8" aircraft ply and some hardwood and some bolts.

http://www.youtube.com/watch?v=LHCatd3XBJ0

This video takes a lot of the mystery out of building multis. Of course he is not telling you that the control KK2 board was flashed to the 1.6 better version update over the original 1.2 version. Night and day here and mainly for more advanced flying. They are also using flashed Esc's for more performance also. But, these are not necessary for entry levels.Like he says the wiring harness is the hardest pain here and even that is not too bad. Use a cheap $2.00 power board and it is even easier.

[Neons]

The Copter was built and test flown in this video. It was setup as a T-copter. The gains in the first video seem on the high side for a Newbee. Try lower gains if starting out. It flies very well.
http://www.youtube.com/watch?v=miD9iwDPssg

here is another homebuilt that is put together by a group of Eggheads. is very nice and flies more sedated. It is aimed at Newbees also. You can learn a lot from these young guys. It is worth subscribing to all their video productions as they do many subjects and novel things.
http://www.youtube.com/watch?v=YCPMC_fiSMI

Setup and final adjustments.
http://www.youtube.com/watch?v=xixni4trNq8

The guys go to a factory here and fly multis with FPV and Hero cameras. Gets better to the end. You will like the camera work here.
http://www.youtube.com/watch?v=TZzRdmQ-Ft4

[Neons]

I finally got my Tri-copter up and running. It was harder for me to setup because the tail rotor was leaning more to port and it kept going left. The tail servo is digital MG servo. It requires additional setting to correct the rotation 180 degrees the opposite. So in the video it explains digital settings at -100. The next problem I had was the tail servo was always seeking and created an oscillation also known to copter fliers as "tail wagging". So with some asking in the RC Groups they told me to drop the P & I gain settings until it gains control.

Finally flew today. Next I worked on trimming and other gain adjustments to get it to hover pretty good without Self Level on. That was in the sub trims in the radio. I added Exponential to my liking and dual rates for more control as I get accustomed to it. I am ready for flying now. I am sure I will be doing more trimming as I learn about this contraption.

Here is a good explanation on setting a Tri to get it at least flyable.The adjustments start about 7:12 minutes in.

.http://www.youtube.com/watch?v=jHN3FJBcFKc

[Neons]

Do things in this order because some things depend on earlier things.
If you choose to do them in a different order, you will undoubtedly get it flying right for now, but later you will wonder why something a little odd happens when you hold your mouth differently as explained below. Too many examples to list on this line.

There are more reasons to do it in this order, these are most of the important ones.

If you absolutely can't fly in with SL turned off, then do it with SL on. I would suggest though that SL off (Acro) isn't really much harder than SL on, as long as all you do is hover, "tail in". It feels more sensitive.

Center the transmitter trims
If you don't do this before adjusting sub-trims with receiver test, your trims will not be centered when flying and you may run out of trim in one direction if they are way off. I personally like my trims exactly in the middle when it is so easy. I find that I do not even need one click of transmitter trim if I follow this procedure.
Adjust transmitter sub-trims to get zeros in receiver test and throttle 0->100
This is the definition of "no drift", if you don't do it now, then if and when you get your copter tuned right, they will be zero then but your trims won't be centered. In bad cases, you might not even have enough trim clicks to trim in some direction. If you do the zeroing carefully, like 2 clicks this way starts to show -1 and 2 clicks the other way starts to show +1, you should have perfectly centered trims when you are hovering level later.
Adjust transmitter dual rates to get max values to be about +- 100
This must be done before trying to arm and fly. If these numbers are way low, the copter may not arm. If too high or too low, the default stick scaling (stick sensitivity) will be effectively changed from the good default values.
Calibrate ESC's
Should be done before trimming, although a well tuned copter can correct for uncalibrated ESC's.
Calibrate Sensors (ACC)
Some versions won't arm till this is done. If done later, ACC trims will have to be retrimmed.
With SL off, take off and trim using transmitter trims
Need to trim Acro [SL off], using transmitter trims before trimming with SL on using ACC trims, because Acro is only affected by transmitter trims, but SL is affected by both transmitter trims and ACC trims and you will get confused when your trim changes when you switch from SL to Acro or Acro to SL. Some people don't use SL. Some people don't use Acro. Many people use v1.6++ mixed mode which uses both of these. If they don't do it in this order, their trim will change from level when hovering to something else when using a lot of stick. E.g. It may only be a small amount, but a sharp roll bank may act like you gave a little pitch as well.
With SL on, take off and trim using KK2 SL menu ACC trims, not with transmitter trims
See previous explanation. Also, ACC trims will hold the SL mode level they are asked to hold where transmitter trims don't hold the level in SL mode. If you use transmitter tirms for this, it drifts back off as if you didn't add enough trim, especially on poorly tuned (I gain too low) copters. Ever seen your SL mode copter need more and more forward stick to stay hovering in the same place in the wind? That is the same effect.
Tune with SL off (PI editor)
Must be done before tuning with SL on because Acro is only affected by PI editor gains, but SL is affected by both PI editor gains and SL gains.
Tune with SL on (SL gain / limit)
See previous explanation.

Added because trims can change a little during tuning:
With SL off, take off and re-trim using transmitter trims
Explained previously.
With SL on, take off and re-trim using KK2 SL menu ACC trims, not with transmitter trims
Explained previously.


Some people choose to do things differently. They may not use a particular feature and don't need to fit it into their setup. I want to understand how things relate to each other so in the future I can use that feature without side effects. This post is for like minded people that are just getting started.