New rotor head - align

[dbargetrex500]

I am currently running the dfc and I have heard horror stories of link failures and boom strikes ect should I just I just park my trex700 e until I can get my hands on this new head?

[Crowbar]

Finally!
I'm a bit worried about using the DFC main shaft though. Isn't it a bit short? The rigid no-flap design of the DFC head kind of prevents boom strikes, but this new one looks like it would allow a bit of flapping.
And are we still using the same dampeners?

[Crowbar]

Also I bet the red will really clash with the color scheme on the speed fuselages.
I was thinking of getting the red/yellow one as I'd like maximum visibility.

[Feral]

Originally Posted by dbargetrex500

I am currently running the dfc and I have heard horror stories of link failures and boom strikes ect should I just I just park my trex700 e until I can get my hands on this new head?

Just make sure your spindle bolts are tight your dampeners aren't worn and your ball links are straight on the swash balls and your sweet.

I own 8 dfc birds and have never blown a link off

[Pitch-Itch]

Originally Posted by dbargetrex500

I am currently running the dfc and I have heard horror stories of link failures and boom strikes ect should I just I just park my trex700 e until I can get my hands on this new head?

The big danger area with DFC is vertical play with the blade grips. (this comes from poor fit from spindle to dampers or worn dampers, again poor fit)

When the blade grips are allowed to move in the vertical plane during flight they can put massive strain on the bolt(s) holding the dfc link to the main grips, causing them to break.

I've only seen one report of this happening, so it's obviously not very prolific. I'd fly without worry, just occasionally check your head.

[utrinque]

I use clone DFC head made by Gartt in two 800 and 700 helis. I was not convinced DFC is good idea. I assume Align DFC head is made with better allu. I did not experience any problems with those clone heads.

Now I prefer DFC just for simplicyty. If someone is going to fly very hard maybe new head is good idea. My DFC heads work also good at low RPM. It was a bit of surprise because Goblin "DFC" head was having vibes at some low RPM range.

It is also good to have choice so plus for Align.

[tomatwalden]

Originally Posted by JohnTC02

Ok stupid question time.

What are the benefits of this head over the DFC, I've only flown the DFC so have nothing to compare it to.

Would I see any improvements for my flying style being a scale flyer and F3C style hovering?

There's an article on "normal" heads versus the DFC approach here

http://www.rchelicopterfun.com/DFC.html

It's a sensible move. DFC is one of the reasons I've avoided Align for a couple of years. I'm sure I'm not alone in that ...

[jsbach#1]

Its interesting they badged it a head for the 700e and n, but not for the 800's.
I wonder if its too soft to work for the monster 800 blades ? I have an 800 pro that I'm dying to change the head on.

[songer121]

Originally Posted by jsbach#1

Its interesting they badged it a head for the 700e and n, but not for the 800's.
I wonder if its too soft to work for the monster 800 blades ? I have an 800 pro that I'm dying to change the head on.

KDE is where you wanna go then... im just not a fan of the red accents all over the place...

[utrinque]

Originally Posted by jsbach#1

Its interesting they badged it a head for the 700e and n, but not for the 800's.
I wonder if its too soft to work for the monster 800 blades ? I have an 800 pro that I'm dying to change the head on.

800 DFC head is exactly the same as 700 DFC. Same part numbers.

So FBL 700 head fits Trekker and 800 PRO for sure.

[JohnTC02]

Originally Posted by tomatwalden

There's an article on "normal" heads versus the DFC approach here

http://www.rchelicopterfun.com/DFC.html

It's a sensible move. DFC is one of the reasons I've avoided Align for a couple of years. I'm sure I'm not alone in that ...

Thanks for the link, it was an interesting read.

They did state in that article that the DFC design is not suited for low head speeds, well I run my Trekker and my 800 Pro at 1050 rpm without any issues, no cyclic wobble whatsoever so I don't know where they got that idea from.

Anyway, I'm not convinced that I would see any benefit from changing to this new head for my flying style.

[utrinque]

No problem with low RPM in my 800 with DFC head.

Servos survived heavy crash when I lost control. New servos are strong.

I do not see disadvantages of DFC anymore. I fly both FBL heads on my 450, 550, 600, 700 and DFC on 700 and 800s.

[tomatwalden]

Originally Posted by JohnTC02

They did state in that article that the DFC design is not suited for low head speeds, well I run my Trekker and my 800 Pro at 1050 rpm without any issues, no cyclic wobble whatsoever so I don't know where they got that idea from.

No doubt I'll get somebody correcting me on this, but my understanding is this ..

DFC needs hard, or no dampening because of the leverage effect that teetering/feathering would impose through the pitch links...

... but you need teetering/feathering to help stabilise the rotor head at lower head speeds, and to counteract the effects of dissymmetry of lift in FFF. Dissymmetry of lift becomes more of a problem with lower head speeds since the delta between the advancing and the retreating blade is higher.

So, DFC isn't well suited to low head speeds and works better with high RPM. But, as you say, it doesn't suddenly stop working altogether and some do fly at low head speeds.

To see if it really causes a problem, you might want to try fast forward flight with your 800 and see if you get an aileron roll tendency .. ??

[utrinque]

Let me share a secret. Gartt DFC head comes preasembled. It is direct copy of Align design. I did not even see dampers in this clone head. It works perfect in three of my helis. One I dissasembled only to check how hard it is to unscrew feathering shaft bolts. I had to use propan butan burner to heat bolt.

I do not care about dampers at all after hundreds of flights of three helis. Over ten today alone. They fly like on rails no mater what RPM.

More... Those heads survived two hard crashes without scratch, one of them in 800. Crashes were caused by electronics so they were not clone kit malfunctions. Anyway I use many Align parts as a precaution.

In modern helis delivering correct voltage to avionics is crucial. That is what I learned. Two power.lines to receivern are essential to feel safe for me.

I still have some low weight 700s with one. but they did not fall in hundreds of flights.

[Excalibur3]

Originally Posted by burn666

Just make sure your spindle bolts are tight your dampeners aren't worn and your ball links are straight on the swash balls and your sweet.

I own 8 dfc birds and have never blown a link off

+1 the only thing you need to watch is the dampers. I pick mine up every flight and make sure they don't move. If they do even a touch I replace them. Only had to once in a year and a half. I still think the DFC head looks way sharper. But I do like the fact the new head won't strip servo gears.

[Pitch-Itch]

Originally Posted by Excalibur3

+1 the only thing you need to watch is the dampers. I pick mine up every flight and make sure they don't move. If they do even a touch I replace them. Only had to once in a year and a half. I still think the DFC head looks way sharper. But I do like the fact the new head won't strip servo gears.

Where are you getting the notion that this new head prevents servo gears from stripping? It's still very possible, but maybe not as likely.