700N DFC Vbar + Cyclic ring

[Delarado]

Guys,

IVe noticed on my 700n I get some horrible elevator input when doing fast rolls (Full aileron input)

Looking at the swash, the ball links are binding on the tops of the swash when giving full aileron input which gives some elevator input too.

Ive reduced my cyclic ring from 85 to 70, the servos seem tohave stopped straining at full aileron input but I still notice the blades move slightly when I have them 90 degrees across the heli and go full aileron input.

Has anyone else had this? whats the fix? Im thinking to either pack out the actuall ball with a washer, or cut some tiny scallops in the swash... Ill post a pic to show what I mean!

[Delarado]

700N DFC Vbar + Cyclic ring

[Obi Wan]

Hi Delardo,

I was flying my 700N DFC Vbar yesterday with no problems.
I will check it out when I get home.

[Delarado]

If you wouldnt mind taking a note of what holes your swash is in etc that would be great.

My cyclic ring is at 70, at 75+ the servos really sing and strain with full aileron input, because the swash binds on the ball links.

My cyclic throw is set at 80 I think.

Agility 80-90-110 depending on bank.

MY balls are in the inner ring (oo-er!)

[Obi Wan]

[ATTACH]60543[/ATTACH]

Sure, I will do when I get home from work.
Looking at your photo, I have made one mod - I changed the DFC links to the older taller style links to get more height to improve head geometry. Not certain weather this will make a difference to the binding issue(?).

Paul

[Delarado]

That might make a difference yes, the links that come in the kit have like a dome shaped moulding, and that is what is hitting!

[Delarado]

700N DFC Vbar + Cyclic ring




You can see the marking

[coolice]

Hey Carl.

I've posted a fix for this mate having spotted it when I got the model;

http://www.rcheliaddict.co.uk/t-rex-...tml#post870197

It's crude but works.
.

[Obi Wan]

Hey Carl.

I've posted a fix for this mate having spotted it when I got the model;

http://www.rcheliaddict.co.uk/t-rex-...tml#post870197

It's crude but works.
.

Ahh, so it's another known problem.
Did you have any concerns about weakening the linkage by dremelling it?

[panosg]

Ahh, so it's another known problem.
Did you have any concerns about weakening the linkage by dremelling it?

I think he Dremeled the Swash plate to give clearance for the ball link!
I will be doing the same on mine tonight!

[Obi Wan]

I think he Dremeled the Swash plate to give clearance for the ball link!
I will be doing the same on mine tonight!

Ahh - OK.

Thanks

[George J]

Had to 'scallop' the swash on my 700e when I first built it as well. Sorted out the binding issue.

[coolice]

Ahh, so it's another known problem.
Did you have any concerns about weakening the linkage by dremelling it?

Evening Mate.

In reality in flight I don't think you'll have a problem, as the swashplate will most probably not deflect that far. However my line of thinking was that if it does it on the ground, it could potentially do it in the air and so I took the dremmel sanding drum to the swash to create the scallops.

No I don't think there is any problems with weakening the swash, you don't need a lot removed as such, it's just a large chamfer to the edge to provide clearance.

Ian

I think he Dremeled the Swash plate to give clearance for the ball link!
I will be doing the same on mine tonight!

Evening buddy.

Spot on, yeah that is all I did. I just took a dremmel sanding drum to the swash, carefully avoiding the steel control balls, as I kept them in as a reference point.

Only thing I'd advise, as I do it when I mod these swashplates, is to put a few layers of tape over the pivot ball in the middle. Essentially I am sealing in the ball in the middle so as to stop any metal filings getting inbetween the ball and socket as I am grinding away.

Ian

[panosg]

Evening Mate.

In reality in flight I don't think you'll have a problem, as the swashplate will most probably not deflect that far. However my line of thinking was that if it does it on the ground, it could potentially do it in the air and so I took the dremmel sanding drum to the swash to create the scallops.

No I don't think there is any problems with weakening the swash, you don't need a lot removed as such, it's just a large chamfer to the edge to provide clearance.

Ian



Evening buddy.

Spot on, yeah that is all I did. I just took a dremmel sanding drum to the swash, carefully avoiding the steel control balls, as I kept them in as a reference point.

Only thing I'd advise, as I do it when I mod these swashplates, is to put a few layers of tape over the pivot ball in the middle. Essentially I am sealing in the ball in the middle so as to stop any metal filings getting inbetween the ball and socket as I am grinding away.

Ian

Thanks Ian.
Do you have any close up photos of the mod?

Edit: Don't worry mate! I just had a look the pictures above and it made it all clear.
I looked the pictures this morning at works useless screen and it wasn't as clear!

[Delarado]

700N DFC Vbar + Cyclic ring

Mine is definitely nose up when doing full cyclic rolls to the right and stays lovely and flat when using half cyclic, so I think maybe it does have an effect! Have reduced cyclic ring now and hopefully will be flying tomorrow so will let you know how I get on!