KDE direct head link for pro dfc 800

[arefim]

I have installed KDE rotor head system in my trex 800 pro DFC.AS you can see in the image I have to thread the ball link only slightly to be able to get zero pitch at mid stick.I'm concerned that it might break during flight. Any one has tried KDE direct Head link XT..?

thanks

[songer121]

i wouldn't fly MY heli like that no way in hell lol...

that said are you using the DFC main shaft??? looks like the main shaft is way to tall....

[arefim]

I do not feel comfortable to fly like that . I will go back to the stock part.There is something wrong in KDE direct design for the rotor head system .They really has to review their measurement again for trex 800 pro dfc.
Thanks

[Bonkievan]

I'm interested to hear the outcome as I've been weighing up to get the KDE XT or SXT head for my 800 also.

However, to the OP,

In the KDE website info it says the XT head "raises the main rotor by 5.0mm" so may mean it's not a direct bolt on and some servo to swash link adjustment maybe needed to compensate? Although, having not installed an XT head on my 800 I maybe wrong to pass judgment, but I agree, there does look to be far too much thread showing on those ball links to Jam nut to be healthy.

On any of my other Stock Align DFC heads I screw those ball links, with collar, all the way into shoulder of the threaded turnbuckle and make most of my pitch adjustments from servo to swash links equally. Once I'm near where i need to be, I only fine adjust pitch on those Ball links from the turnbuckle 'type' stud one or two turns out from the collar shoulder max.

I would perhaps post this on the KDE forum as the KDE rep frequents there a lot or, alternatively, email them directly to get clarification.

[Mike A.]

Maybe they accidentally sent you 600 control links? It definitely isn't supposed to be like that by design. Do not fly it like that.

Email KDE, Patrick will get back with you right away.

[DerClown]

In first place why in the world to change brilliant Align DFC head with aftermarket stuff ?
Just fly like it is. Keep ALIGN helicopters stock and they will fly without any troubles...

[Bonkievan]

There's nothing wrong with the Stock Align kit, derclown.
However, Align produce their kits cost effectively and like most things done like this, can be arguably improved by aftermarket parts. Whether that be by using better grade metal, better design, tighter tolerance control or all of above, improvement can be had. Personally, the beefier ball links are a great upgrade.

Now, whether you want to is personal choice. That's what's great about this hobby

[Mike A.]

Hold the KDE control link up next to the stock Align link. They should be the same length...

[arefim]

The control link is the same length like the align one.The main shaft for 800 pro DFC is 1 cm longer than the main shaft for 700 pro DFC. KDE made the head system based on the main shaft for 700 and not taking into consideration the new length for 800 main shaft.

[Mike A.]

Wow, that's interesting. I see that the part numbers between the 700-800 are the same. Did you contact KDE? One option may be adjusting your servo to swash lengths to make them a bit longer....raise the swash. That will give you some headroom on the pitch links. Maybe that will help?

[arefim]

I think for any one interested to get KDE head rotor system for 800 Pro DFC ,he has to use main shaft for 700. Adjusting the swash length to make them longer will move the weak point in the system one step down.

[Bonkievan]

Correct me if I am wrong, and I'm not at home to check, but im pretty sure the 800 shaft is longer to compensate for the taller frame of the 800???

Therefore, if you used the 700dfc shaft, you would make this a prime boomstrike candidate....best case scenario? ??

[arefim]

When I talked to Patrick he indicated that with 700 main shaft , the head will be shorter by 1/2 cm at the end because kde rotor head is 1/2 cm longer than the stock one.
Upgrading really should be fun and worry free process and I do not feel this upgrade achieves this as there are a lot of questions and concerns associated with this upgrade

[Bonkievan]

Originally Posted by arefim

Upgrading really should be fun and worry free process and I do not feel this upgrade achieves this as there are a lot of questions and concerns associated with this upgrade

I agree. You are paying a premium for these products too. I'm just baffled that KDE would advertise '800 compatible' without 'fit testing' first.??
But hopefully Patrick has given you the answers you require or offered some sort of reparation, if indeed this product is not compatible with the 800 as advertised. From what I've seen and heard, he's a straight up guy

[Mike A.]

Originally Posted by arefim

Adjusting the swash length to make them longer will move the weak point in the system one step down.

I don't think raising the swash by 2-3 mm would weaken anything. You would still have plenty of thread on the swash to servo links.

If you use the 700DFC mainshaft the head height will end up the same as a stock 800DFC. The KDE headblock is a bit taller.