Thread Tools
Nov 20, 2008, 09:03 AM
planepainter
planepainter's Avatar
Kevin, I find the setup you contributed to be interesting. And it has advantages that some of the others don't. I assume that the spoiler is closed by the weight of the servo and air pressure? I can see how the tab at the left keeps the spoiler from opening. Don.
Sign up now
to remove ads between posts
Nov 21, 2008, 12:38 PM
VegasRay
Thread OP

EZ Spoiler Linkage Photos


If you missed it, Rob Glover has just installed the EZ spoiler linkage in his new Miles 2M build in the Thermal forum. Click on the following link https://www.rcgroups.com/forums/showthread.php?t=853850 and go to Pages 18 and 19, items # 263 through #273 for Rob's installation photos. As usual, Rob has done a great job of explaining and photographing his methods.

Ray
Nov 21, 2008, 01:45 PM
agony sweetns the victory
atjurhs's Avatar
Ray,

I don't have any mechanical engineering background, but I'm always wondering about "optimal" and maybe there's really only fractional differences, but here's my question:

In posts 22, 24, and Rob's Miles post (and the way I've implemented a sliding spoiler linkage), the far end of the pushrod is afixed to the control surface (but allowed to pivot). In the 1st post of this thread, the near end of the pushrod is fixed to the servo arm and the far end is allowed to slide.

From a mechanical engineering perspective, what's the pro/cons of the two methods ???

Todd
Nov 21, 2008, 04:05 PM
VegasRay
Thread OP

Todd


Quote:
Originally Posted by atjurhs
Ray,

I don't have any mechanical engineering background, but I'm always wondering about "optimal" and maybe there's really only fractional differences, but here's my question:

In posts 22, 24, and Rob's Miles post (and the way I've implemented a sliding spoiler linkage), the far end of the pushrod is afixed to the control surface (but allowed to pivot). In the 1st post of this thread, the near end of the pushrod is fixed to the servo arm and the far end is allowed to slide.

From a mechanical engineering perspective, what's the pro/cons of the two methods ???

Todd
You have an interestesting question concerning the fixed attachment points versus the sliding function. Considering your two observations, the total arc distance traveled by the spoiler attached connector remains the same regardless of the setscrew attachment point. The pivoting function of that connector also remains the same. The constantly changing curvature travel, due to the displacement of the servo pivot point to the spoiler hinge line, also remains the same under either condition. The single variable would be the sliding friction between the slider rod and the connector(s).

With the spoiler connector having the single set screw, the sliding friction on the rod would be caused by the two connectors on the servo arm. When the single set screw is attached to either one of the servo connectors the sliding friction would be caused by only one connector, at the spoiler mount. Inasmuch as the sliding friction is miniscule in this application, regardless of the location of the setscrew, the physical movement of the spoiler would not be affected by the frictional forces of the slider rod/connector(s) interface.

My personal concern with the setscrew location would only be having easy access to the setscrew with my screwdriver. Hope this helps.

Ray
Nov 21, 2008, 11:39 PM
Mongo like wind. Wind Good.
V1VrV2's Avatar
You guys might be interested in the lock down for the spoilers in flight.

If you use the servo to hold pressure down on the spoiler to keep it closed you are in for alot of audible protest from the servos (buzzing) especially with the HS-55's.

Here's a link from a thread I posted June of 2007:

https://www.rcgroups.com/forums/show...erhawk+spoiler

You can use 1/8" rare earth magnets from Radio Shack and glue them to the spoiler then use a small screw as a attractor glued to a small wood block in the wing. When the spoiler panel approaches closed, the magnet attracts to the screw and locks the spoiler down without the servo holding it down. No servo pressure required. The attract force can be fine tuned for your servo (these magnets are REALLY strong) by turning the screw in or out to adjust the gap between the magnet and the screw when closed. This method will work for any spoiler installation and hardly adds any weight. When the spoilers close, you can hear them "click" into the lock down position.

The two small circular objects on the underside of the spoilers are the magnets. The screws are mounted in the wing and are not directly visible.

Simple and effective.

Tony
Nov 22, 2008, 10:33 AM
Registered User
Neil Stainton's Avatar
I don't understand why people are enthusing about this linkage. The setup shown in post 14 is better because:

- it can use all of the servo movement, and thus all its power.

- by maximising the servo's rotational movement, fully open and fully closed can have nearly straight linkages, ensuring minimum torque is transmitted to the servo.

- it is not so dependent upon the servo's posional accuracy for good spoiler closing.

- it is also easy to implement.

Just my opinion, no slurs intended.

Neil.
Nov 22, 2008, 05:33 PM
Registered User
V1VrV2 described the use of rare earth magnets to hold the spoilers down. When I have used this technique, I have enlarged the holes in the control arms so that there is "slop". When pushing the spoilers up, the slop doesn't matter. When pulling the spoilers down, I adjust the end point of the servo so that the linkage is in the middle of the "slop" range. That way, the servo is putting out zero torque when the spoiler is down. This assures that the spoilers don't cause a constant battery drain.
Nov 23, 2008, 05:24 PM
Registered User
R. Carver's Avatar
Quote:
Originally Posted by Neil Stainton
I don't understand why people are enthusing about this linkage. The setup shown in post 14 is better because:

- it can use all of the servo movement, and thus all its power.

- by maximising the servo's rotational movement, fully open and fully closed can have nearly straight linkages, ensuring minimum torque is transmitted to the servo.

- it is not so dependent upon the servo's posional accuracy for good spoiler closing.

- it is also easy to implement.

Just my opinion, no slurs intended.

Neil.
That setup would be much better if the servo was rotated 90 degrees. And even then, six of one, half dozen of the other
Dec 02, 2008, 12:43 PM
.: Looking for Thermals :.
Ricardo RW's Avatar
Recently I added spoilers to my Fling 2M and used this setup.




It closes very tightly and deploys the spoilers to 90.


Dec 02, 2008, 02:41 PM
Hot Dawg Glider Pilot
schrederman's Avatar
Nicely done Ricardo...

Jack
Dec 02, 2008, 02:59 PM
Registered User
Andy W's Avatar
el neato!
..a
Dec 02, 2008, 06:27 PM
High Lift Coefficient
Sailhigh's Avatar
Ricardo,
I've been thinking along the same slider concept. You've proven that it does work. Great job.
Dec 02, 2008, 08:31 PM
Registered User
I've used something like this except that I let the magnet bottom on the screw head and use the screw to adjust the spoiler until it is exactly where I want it. I can control the force by using a smaller screw or one with a round head instead of a flat head. Of course the really light way is probably to use a flat head screw that's very small. I then use a torque rod for a bit of return force and only PUSH the spoiler with the servo so that unless the servo goes WAY over, it can't stall. BUt I haven't decided on my favorite way of pushing the spoiler, unless it's the traditional strings.
Quote:
Originally Posted by V1VrV2
You guys might be interested in the lock down for the spoilers in flight.
snip
You can use 1/8" rare earth magnets from Radio Shack and glue them to the spoiler then use a small screw as a attractor glued to a small wood block in the wing. When the spoiler panel approaches closed, the magnet attracts to the screw and locks the spoiler down without the servo holding it down. No servo pressure required. The attract force can be fine tuned for your servo (these magnets are REALLY strong) by turning the screw in or out to adjust the gap between the magnet and the screw when closed. This method will work for any spoiler installation and hardly adds any weight. When the spoilers close, you can hear them "click" into the lock down position.
snip
Tony
Dec 04, 2008, 04:11 PM
VegasRay
Thread OP

AVA with E/Z Spoiler Linkage


After several questions about converting an AVA with the single blade spoiler to the E/Z spoiler setup I decided that a picture is still worth a thousand words. OFB 'Mac' Crockett just finished converting his AVA to the E/Z setup. Mac removed the original servo/linkage and installed the E/Z setup in the second rib bay in less than an hour. He used a HS-56H servo and a small nylon arm, that he had in his junk drawer.
Dec 29, 2008, 07:48 PM
The Truth is Not Forgotten
Lincoln you could use a small ga. pull pull wire and then use the spring to colse them


Quick Reply
Message:

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Du-Bro Mini E/Z: How to make them rotate freely? tom_yellowblue Parkflyers 12 Aug 28, 2002 05:02 PM
E-Z Flight.com web page up and running. balsaman Vendor Talk 0 Mar 17, 2002 04:51 PM
Dubro E/Z link too small for HS-55 Peter Mar Parkflyers 5 Dec 17, 2001 09:42 PM
E-Z 400 Feodosia Flyer Parkflyers 1 Jun 27, 2001 02:45 PM
Anyone know of a "mini" e/z connector? Travis Sport Planes 4 Jun 07, 2001 01:17 PM