HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old May 09, 2014, 01:20 AM
Ex AmA mEMBEr
mchldpy's Avatar
United States, CA, San Bernardino
Joined Feb 2010
744 Posts
Discussion
Fuselage bracing and Ackerman Effect attachment points

Hello,
Has anyone successfully braced just one side of the lower fuse on a 3d profile with carbon rod? If so, does it matter which side? I'm wanting to do a pull-pull setup on the elevator but the braces are already installed. I searched but RCG's search app just doesn't like myself or my syntax much.
PLEASE READ BELOW
mchldpy is offline Find More Posts by mchldpy
Last edited by mchldpy; May 09, 2014 at 05:38 AM. Reason: more info
Reply With Quote
Sign up now
to remove ads between posts
Old May 09, 2014, 04:45 AM
Ex AmA mEMBEr
mchldpy's Avatar
United States, CA, San Bernardino
Joined Feb 2010
744 Posts
I just read that if I induce some "Positive Ackerman Effect" I might avoid some of the bracing due to the 'offset hinge-line' setup procedure.
My new question is, does 'Line B' have to attach to the servo arm @ the inner point (black slotted line) which will decrease the amount of force applied to the control surface when that side is pulling OR can it go to the red line on the outside? To achieve the "Positive Ackerman Effect" the control horn attachment points must be equidistant from the offset hinge line BUT, will the other end make any difference?

michael clyde
mchldpy is offline Find More Posts by mchldpy
Last edited by mchldpy; May 09, 2014 at 05:32 AM.
Reply With Quote
Old May 09, 2014, 06:29 AM
serial scratchbuilder
Granted's Avatar
Canada, BC, Mission
Joined Sep 2012
1,260 Posts
Attach line B to the outer point at the servo, using the inner point will introduce bind as the line is travelling less distance than line A.
Granted is online now Find More Posts by Granted
Last edited by Granted; May 09, 2014 at 07:51 AM.
Reply With Quote
Old May 09, 2014, 07:08 AM
Old age is not for sissies
Azarr's Avatar
Dayton Intl, Ohio, United States
Joined Jan 2000
7,683 Posts
You'll just have to try it, ideally you want the distance to the line attachment point identical at both the servo horn and control horn as originally drawn.

Granted: pretty sure the lines will travel the same distance because of the offset hinge. They would travel different distances if the hinge line were centered.

Azarr
Azarr is offline Find More Posts by Azarr
Reply With Quote
Old May 09, 2014, 07:53 AM
serial scratchbuilder
Granted's Avatar
Canada, BC, Mission
Joined Sep 2012
1,260 Posts
Quote:
Originally Posted by Azarr View Post
Granted: pretty sure the lines will travel the same distance because of the offset hinge. They would travel different distances if the hinge line were centered.

Azarr
At the hinge, yes, but we're looking at the servo end here.
Granted is online now Find More Posts by Granted
Reply With Quote
Old May 10, 2014, 08:17 AM
Ex AmA mEMBEr
mchldpy's Avatar
United States, CA, San Bernardino
Joined Feb 2010
744 Posts
While I may not know whether or not attaching to the outer point on the servo will work or not, I do know that it does travel less distance but only half the time. The other half of the time the other side is traveling less distance. That is the result of placing both control horns behind the hinge line, to achieve the Positive Ackerman Affect. Until now, I've only used it on a 'centered (vs an offset) hinge line' where both control horns are are an equal distance from the fuselage but still behind the hinge line and one side travels less distance but only half the time. I would like to be able to attach to the outer point but your reason (will bind because it's traveling less distance) is what I'm wondering about.

thanks for your answer,
michael clyde
mchldpy is offline Find More Posts by mchldpy
Last edited by mchldpy; May 10, 2014 at 08:40 AM.
Reply With Quote
Old May 10, 2014, 08:41 AM
Ex AmA mEMBEr
mchldpy's Avatar
United States, CA, San Bernardino
Joined Feb 2010
744 Posts
thank you Azar
mchldpy is offline Find More Posts by mchldpy
Reply With Quote
Old May 10, 2014, 10:02 AM
Ex AmA mEMBEr
mchldpy's Avatar
United States, CA, San Bernardino
Joined Feb 2010
744 Posts
Just so I'm not confusing the issue, the drawing did not originally have the servo or the slotted line. It was added by myself to help illustrate my question. That's why I'm wondering whether or not the outer attachment point will work.

michael clyde
mchldpy is offline Find More Posts by mchldpy
Reply With Quote
Old May 10, 2014, 04:16 PM
Build straight - Fly twisty
Whiskers's Avatar
Australia, QLD, Little Mountain
Joined Feb 2010
4,142 Posts
Quote:
Originally Posted by mchldpy View Post
<snip> That's why I'm wondering whether or not the outer attachment point will work.

michael clyde
Yes! That is the right setup.
Whiskers is online now Find More Posts by Whiskers
Reply With Quote
Old May 10, 2014, 08:51 PM
Ex AmA mEMBEr
mchldpy's Avatar
United States, CA, San Bernardino
Joined Feb 2010
744 Posts
Hey Whiskers,
Just so I don't mess up and have to drill and re-floss, a real pain, you say the outer attachment point will work?

michael clyde
mchldpy is offline Find More Posts by mchldpy
Reply With Quote
Old May 10, 2014, 09:15 PM
Build straight - Fly twisty
Whiskers's Avatar
Australia, QLD, Little Mountain
Joined Feb 2010
4,142 Posts
Yes.
You want the lines to be equidistant from the servo pivot and also equidistant on the rudder horns, measured from the hinge line.
So the line on the rudder horn away from the hinge will need to come in-board by an amount equal to the rudder thickness.
Whiskers is online now Find More Posts by Whiskers
Last edited by Whiskers; May 10, 2014 at 09:22 PM.
Reply With Quote
Old May 10, 2014, 11:36 PM
Ex AmA mEMBEr
mchldpy's Avatar
United States, CA, San Bernardino
Joined Feb 2010
744 Posts
[QUOTE]
"Yes.
You want the lines to be equidistant from the servo pivot and also equidistant on the rudder horns, measured from the hinge line."
[END QUOTE]

Got It.

[QUOTE]
"So the line on the rudder horn away from the hinge will need to come in-board by an amount equal to the rudder thickness."
[END QUOTE]

um, ok...

thanks,
michael clyde
mchldpy is offline Find More Posts by mchldpy
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Sold rc baja lower chassis brace $49 for $35 FPVcrazyman Cars - Cars and Parts (FS/W) 0 Feb 08, 2014 02:52 PM
Sold rc baja lower chassis brace $49 for $35 - $35 FPVcrazyman Cars - Cars and Parts (FS/W) 0 Jan 21, 2014 08:29 AM
Build Log Full fuse Sukhoi SU-26MX based on the 3D Foamy Profile ukdalai Foamies (Scratchbuilt) 4 Nov 29, 2010 07:32 AM
Removable Wing on Profile Fuse? Seared Ice Modeling Science 16 Jul 10, 2004 12:58 PM
How do you keep wings straight on a profile fuse ssyed Foamies (Kits) 5 Jun 16, 2004 10:04 AM