Hey Rob, I think you are one from youtube that I had come over here. If so, here is what I couldn't type on there.
The first thing you need to do is visit the link below and download the manual that fits your heli.
Rc-Help - Instruction Manuals
Once you get it downloaded, you need to find the measurements of all of the links on your helicopter. It will give you the measurement from center ball to center ball. Get this as close as you can. If you are using the pro frame, then all of your swash links will be the same length. It will take a bit, but it will be the perfect starting spot. Make sure that you are screwing each end on the same distance (ie, one is not showing threads and is bottomed out when the other only has a couple threads screwed in it).
Once you have all the links measured out correctly, now you need to set your servo arms at 90* to the links at mid stick. Make sure your pitch settings have mid stick at 50 if you are using the DX6i. You will also need to have your throttle hold on. Check that throttle hold (or "hold" in the menu) is at 0% on throttle curve all the way across. This will keep the motor from spinning. But it's always best to unplug two wires. Then, make sure the pitch curve on hold is 0, 25, 50, 75, 100. This way you can set your pitch here in a second.
Once your servo arms are centered with subtrim (your trim should still be centered), now you need to put your pitch gauge on the heli at mid stick. Adjust the 3 swash links until you get to 0* of pitch. Once that is done, go to full positive pitch. You should be around 11* of pitch. You shouldn't need anymore but we will adjust this later. Once you get that number, check your negative pitch. If the numbers are the same, then you are done. But if your numbers are off, then we need to do some link adjusting.
If your positive pitch is more than the negative, then you need to make your swash links to servos shorter. One turn at a time. This part takes forever. Don't worry about mid stick right now. If your negative pitch is more, then your swash is too low. Adjust that until your positive and negative numbers are exactly the same.
Now, put your radio at mid stick with hold on, and check for 0 pitch. If you are dead on, or off by just a hair, you are done. If it's off, adjust either the grip to mixing arm links, or the mixing arm to swash links until you get to 0 pitch at mid stick. Once you are there, check your positive and negative again.
Setting up the head can take hours, and you will need to take a break before you throw the heli through the window lol. But, once you get everything setup perfect, it will be worth it. Remember, when you crash, it's unlikely you are going to break multiple links, and there is always a double of it so you can get new ones to match it to. The exception is for those where the pitch and aileron servos are stacked on top of each other, then one of the swash links will be unique. But, the grip, mixing, and washout arms all have doubles.
I hope this helps you out. Like I said, I could not put this into the youtube comment box. If I skipped over something (I don't think I did, but just in case) let me know and I will cover it. I have not flown a heli in months so I'm having to really think about this again lol. But it's all good, I need to start flying my heli again.
Welcome to the forum!