First off it looks like I have to have everything reversed in my radio. Down on the swash is up on the blades and left is right. I also need to ether turn all the links way shorter or move the swash clamp down. One more I have seen other heads and the swash clamp is about 1/4 or more off. Keeping the links all at a angle. Mine seems to be just a little off, this could be why the links are to long.

Ok,

To cure your backwards collective problem you have to go into the swashmix menu on your transmitter and turn the pitch sensitivity to negative what ever the number is at present. (I didnt know about this until after about a year of flying, and when I had a backwards swash problem, I would just run a backwards pitch curve O.O )

As for roll/pitch being reversed - just find the servo reverse function on your tx and flip the appropriate settings.


Setting up a multi head is quite easy once you get your head around a couple of basics.

To take care of phasing you must align the anti rotation arm on the mainshaft such that:

-Ignoring collective, when you have a blade over the tail boom, it should move only to roll, and should not move when you input pitch. Also, it should move in the correct direction, ie. for a clockwise rotor head, when you input left roll, the blade should tilt anti clockwise and vice versa.

-Same for when you have a blade 90degrees out the side of the heli, when you pitch forward, it should turn anti clockwise etc. No roll inputs should have any effect on this blade.

As for collective, I don't have much experience with setting up 450 size multi heads, but I have heard you do not need any negative pitch, as in stick down should be set at 0 degrees.

You could also put some gyros on pitch and roll axis to calm it down a bit as multi heads are quite "responsive" - or you could look at a flybarless mixer to help depending on your budget, the cheapest flybarless mixer is the gaui unit wich is about USD$200

Hope this helps - and that is an awesome looking bird!

Good Luck!

For collective, just a touch of negative pitch, for wind.
Try using a 45-45-50-75-100 pitch curve.

A couple of techniques to tune down the multi head responsiveness include:
1. Tune down the swash mix. let's say your ail-elev-pit mix is 60-60-60. Lower it to 50-50-50 for example. All three numbers don't have to be the same. Tune each one to your liking.

2. Apply about 30% or more Expo to the Ail and Elev. Tune to your liking.

3. Move the servo to swash servo horns closer to the center of the servo horn.

Thank' alot guys this page is going to became my 5 blade setup bible.

I am wondering what that tail motor can handle with 5 bladed head and the weight of the large fuse if that comes from Honeybee FP or CP tail. Let us know how it does.

This tail is from the venom night ranger and has the largest of all electric drives, but if it comes down to it not working I will just get a brushless motor and larger prop.

Ok I worked on the head today and I think I got the anti rotation arm set good for now. Wow it was way off. In the pic the blades are set as flat as I could and the anti rotation arm is just slightly up.

Mhills,
Can you advise the fuselage maker and what is its dimension.
Thanks.

-shim

Try and get the anti-rotation bracket level at 0° pitch

Originally Posted by shim

Mhills,
Can you advise the fuselage maker and what is its dimension.
Thanks.

-shim

I think it's from darthdrk: http://darthdrk.4t.com/photo3_4.html

yes it's darthdrks 450 size CH-53.

One other question? If at the most I will only have 1 to 2 degree negative pitch why would I want the anti-rotation bracket level at 0° pitch? I would thing you would run into less binding by having the anti-rotation bracket level at +2 or +3° pitch

With your blades all at 0 pitch, loosen the set screw on the anti rotation bracket and move it up to get your 90 degree.

It probably wasn't installed in the correct position on the assembly line.

Originally Posted by mhills51

yes it's darthdrks 450 size CH-53.

One other question? If at the most I will only have 1 to 2 degree negative pitch why would I want the anti-rotation bracket level at 0° pitch? I would thing you would run into less binding by having the anti-rotation bracket level at +2 or +3° pitch

I don't think you need anything more than -2 degree negative pitch with multi bladed head.

Here are some close ups of the head. I got it off ebay for $109. Took all the links off and checked all the blade holders. They were all smooth and everything was overly loctite. I had to us a lighter and pliers to get one of the balls off.

I would think that if you wanted to have it level at 4° it should be OK.
The reason level at 0° is so that you would have full travel to lets say -10° to +10° and it would be in the center at 0° pitch.
So if you run -2°+10° the center would be at +4°
Which means I should re-adjust mine, since I am now running at -2.5°+11°