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Old Jan 29, 2013, 03:19 PM
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If you want to use spoilerons,i would set the link slightly in front of the hinge line(when hinge is at the top surface of the wing) to get more throw.
This would cause a mechanical positive differential.
At Bens solution it looks like link its set behind the hinge line which would give a negative differential.
But this may deceive, usually the ailleron surface is a bit wider at the lower side of the wing than at the top ( when hingeline is at the top)

DIfferential has to be adjustetd specific for every plane(and preference);some positive differential is usual.

Yello
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Old Jan 29, 2013, 03:26 PM
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DUP;
I have some 2mm prepreg.carbon out of F1 production , even this stuff i would not trust for an application with a sidebolted ball joint!
But as i am happy with my simple steelrods i can save the expensive stuff for motormounts

Yello
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Old Jan 29, 2013, 03:32 PM
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I think good tight L-bends are enough for this applications and planes, at least 1.5mm thick...

nothing complicated, and does the job...
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Old Jan 29, 2013, 03:39 PM
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Quote:
Originally Posted by Mreyello View Post
DUP;
I have some 2mm prepreg.carbon out of F1 production , even this stuff i would not trust for an application with a sidebolted ball joint!
But as i am happy with my simple steelrods i can save the expensive stuff for motormounts

Yello
Seriously? I'm clearly not understanding something here then. There's no way you'd twist one of those with a servo. I would have thought the failure point would actually be where the horn mounts into the control surface anyway....
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Old Jan 29, 2013, 04:06 PM
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Side bolted ball joints are nothing new Yello. Not mechanically perfect, but mechanically adequate for most applications for an aileron that has what? 1kg of load on it? I think a short, fat,plastic servo control horn with a side mounted ball ain't going nowhere.

I doubt I could twist a 2mm thick control horn sized piece of prepreg with my hand...

The differential issue can be easily adjusted with end point adjustment in the radio, no biggie.
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Old Jan 29, 2013, 04:06 PM
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Even small flexability may give the starting point for high frequency movement which may swing up into heavy flutter.
Do not underestimate the forces in a swinging system.

I am pretty sure the horns DUP recommended will be safe, and sure the prepregstuff will be reliable aswell but for me there is no need to split forces into bending forces and torsion forces when there is the option to reduce it to just bending forces which are easier to controll.
This is for sure a more or less theoretical discussion, it is obvious that there are lots of nice working balljoint linkages out there.

But its not the way an engeneer would design!

Yello
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Old Jan 29, 2013, 04:42 PM
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When I tried to use ball links, I was unable to get the ball close enough to the servo hub because of the nut on the screw. Having the link further away from the axis amplifies any slop and/or floating neutral problems. So I stuck with Zs and Ls.

But let's not get hung up with which method is better, the differences are small and racing on a course has difference requirements anyway - such as precise neutrals.
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Old Jan 29, 2013, 05:00 PM
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Darron
It was not my intention to offer my method as the best,just wanted to show the pros and cons.
Knowledge about the mechanical basics will help to avoid bad experience.

I remember one guy to have a flutter issue which he tried to solve with longer arms both sides,for me the wrong way in the case he used ball joints(i can not find the thread,sorry)

As flutter is a general problem we should open a specific thread about linkage and servos to avoid the impression flutter is a swist problem ( which definitly is not the case!!!)

Yello
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Old Jan 29, 2013, 11:28 PM
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What size prop would be good for a mild hotliner setup for sport flying. Say about a 1000 watt power system?
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Old Jan 31, 2013, 07:08 AM
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My maiden flight was yesterday
My set-up :
Strecker 260.15.7
4S
14.5X14
The flight itself went very well - plane flew great with amazing climbing power - Until I landed - I accidentally turned the throttle on when the plane was on the ground and burned out my Strecker.
This is a motor that cannot be easily acquired - they're like rocking horse pooh. It was graciously supplied by RolfD (FD-Modellbau) from his personal collection. Its had over 400 flights without an issue. One flight with me and its toast. Im sending it back to him for repair.
Needless to say Im feeling a bit sheepish.
But all is not lost - my Scorpion 3026 1900kv awaits !
Hopefully my luck changes with this plane.
Blitz - please post pics of your motor mount. How are you planning on making it?
Im thinking I'll do a carbon plate/ply/carbon plate one.
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Old Jan 31, 2013, 12:31 PM
The Prop is Where its At!
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Heya cheif!! aaaa true-guted,sorry to here,lesson learnt
Gd to hear people being geniune with there ups-we all make them.
I've drawn a ruff plan-at this stage,alloy inner and ply outer.Will post a pic when i draw it up a bit neater
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Old Feb 04, 2013, 01:56 PM
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magrinsi's Avatar
Florence Italy
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[QUOTE=blitzu;23848224]
Quote:
Originally Posted by jrandle View Post
Blitzu, could you please take a photo of the bottom of the wing and tailplane so we can see those colours as well. Starting to feel the itchy purchase finger syndrome.....

hehe too gd-exactly like me... . master card!
Heres the underside of wing...


The wing is soooo pointy and thin...reminds me of a knife
What is this in photo?
Another question ..the nuts of the 2 screws are glued in the fuse?
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Old Feb 04, 2013, 05:49 PM
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[QUOTE=magrinsi;24031687]
Quote:
Originally Posted by blitzu View Post

What is this in photo?
Another question ..the nuts of the 2 screws are glued in the fuse?
What you have circled is the tab on the leading edge of the wing that slids in the fuselage...As for what the wing bolts screw into,they are triangle threaded plates that are glued in the fuselage.
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Old Feb 04, 2013, 11:47 PM
The Prop is Where its At!
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Howzit Magrinsi couple of pics of tab and inserts..
Tiny little tab too (gets me worried looking at it ),ovisly plenty strong enough thou
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Old Feb 05, 2013, 01:29 AM
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Florence Italy
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But i must cut in this zone the fuse for insert the tab?
How do you have do for remove the fiber of kevlar around the cur of fuse?What do you think of use a llittle quantity of resin and glue the fibers?
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Last edited by magrinsi; Feb 05, 2013 at 03:12 AM.
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