PROBABLY still has got junk for hardware so be sure to replace it before you build. at minimum the pushrods

damn it feels good to be a probro! i got a few flights on my primo and it has replaced the extra quite well. although that extra flew quite nice and felt very predictable, the primo blows it out o da water! and i can tell you that i got a lot less time in building that bird than all the time i lost trying to get satisfied by great planes.

WORD!!!!!! It is good to be a BRO!

I thought you'd like that Primo

I am definitely going to get a Mojo 60, but in the mean time, I read this thread and looked at the hardware on my new Seagull Extra and it looked pretty much like the same 2mm crap that failed. So, I replaced it with some of the new aluminum Sullivan ball links, titanium 4-40 pushrods and a new clevis with locking pin. Definitely no slop and flex as compared to stock and only 1 gram each heavier. Unfortunately, the weather is not conducive to flying right now...
Stock versus new stuff:



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Hi Robinsp,
I have Dumb Question for you ,
Do you have all your "hinge gaps Sealed " ???????
Also check your elevators to see if they are deflecting the same ?
Try moving the control rod out to the end of the control horn ( for more lexerage ) ...

Just A BrainFart , OH Well [:-]

Later,
Mark K.

that has been discussed...and im not sure youre on the right page with your train of thought.[sm=spinnyeyes.gif][sm=spinnyeyes.gif]

Hi Robinsp,
oh My Bad,,,,
Did not read the Whole thread ,
the Question still remains The Same ??????
Never Mind, [sm=lol.gif]

i hear ya. ive had flutter on 2 models before. one i was able to save, the other was my trainer after the ca hinges on the elevator were starting to pull out... learned the hard way.

Got this plane from my lovely wife for Christmas and took great care building it. I have been flying a Twist with a saito .82 for about a year and wanted a pattern plain. The build went great with few problems. The first flight went off flawless but I was flying quite slow getting things trimmed out and practicing approaches so I could get it on the ground in one piece. My second flight I made a fairly fast pass out of a dive at idle throttle and could hear a loud buzzing and then i could see the right aileron partially separate from the wing . It went into a right bank and on low rates I did not have the rudder to correct and it crashed. I found both aileron servos stripped the left aileron horn snapped off and the right aileron ripped the ca hinges out of the wing and was hanging on by the push rod. Since it crashed nose first the wings were in perfect condition so I knew it was flutter that caused these problems. After contacting great planes they referred me to a flyer that should of been included with the kit on setting up the servos. After pleading my case to Tower hobbies and sending back the plane, I am pleased to say the replace the plane at no cost (I just had to send what was left of the old one back). I have never experienced aileron flutter this badly and hope the second build goes better. I hope anyone who does this build in the future does get this flyer and does not set up the controls as shown in the manual or they might very will end in a crash as mine did. Thanks Tower Hobbies for their support and giving me a second chance on this one..............

im glad they were able to help you out, Mlkissel! I would definately put 4-40 control rods on the next one. maybe even some ball joint linkages on the control surfaces.
i must say that this extra is a beautiful airplane! have fun.

robbinsp

The manual does not show the aileron setup all the way in.

Robin,
Why were you using Z-bends instead of the stock hardware... [sm=idea.gif]

where is this "flyer" GP directed your attention to?

edit:

http://manuals.hobbico.com/gpm/gpma1022-tech2.pdf

i was not impressed with the nylon wirekeepers. maybe thats the whole problem!

That is the one,

http://manuals.hobbico.com/gpm/gpma1022-tech2.pdf

it is referred to as manual 3 on the tower hobby page for the extra 300sp. Apparently it was supposed to be included with the manual. I do agree with the above comment that the manual does not show the hookup of the aileron servo links, however it does show the rudder elevator combination connected in the "EXTREMELY DANGEROUS PUSHROD HOOKUP" as referred by the tech notice flyer. I never thought their would be a problem hooking up the ailerons this way. I have a Twist with standard servos, and all the controls are hooked up for maximum throw. I have never had any problem with flutter. I did like the way the extra flew, so this time I will try metal gear servos, 4-40 pushrods and even some of those counter balance weights I saw on another post. If nothing else, its a hard lesson learned.........

I was looking at your pic and i was wondering if you have your servo grommet bushings installed upside down? just thought id ask since i would hate to see anyone make a mistake and pay for it like I did.

...forgot to upload the picture that i was asking you about here it is

Good catch, thanks!

here also

...

I felt pretty silly when someone pointed out to me the metal grommets were upside down; I used to put them in that way too!

well i have contacted GP for one last time regarding my case. I will let you all know what happens.

Wow I just bought the Extra 300sp model Jan 4th and I did not see any proper push rod hook up procedures in the manual?? I bought it from a Hobby Shop so maybe they had this model on the shelf for a while. I am to the point of installing the control horns and linkage. After reading all of this I think I will hold off and buy the 4-40 push rods.....ghoffman , your set up looks really good. I agree a plane that cost $200.00 should have the hardware to be able to fly the plane like it was designed. I also agree that the materiel used in some 2-56 push rods can be a cheap grade of material....We should not have to pay 200.00 then have to go out and buy quality hardware to ensure that is is safe to fly?? This is obviously not a trainer plane so the guys and girls that buy it will put it threw the ringer. We can accept a crash or at least get over it if we made a mistake, but when you loose a plane because of a flutter that snapped the push rod in half and bent the other one you have to wonder what grade of push rod material are in these ARF's?? Thanks for the insight....

Well, my second build in a month is now finish....first one lost to severe aileron flutter. Now if it would just stop snowing on my runway! Has anyone ever tried to put skies on one of these things. I will try to upload some photos of my build and pass along advice (for what its worth). Wing build, I upgraded pushrods to 4-40 and used MG servos this time. Mounted pushrods on the outer horn of aileron and one hold down on servo; also made a mass balance weight for both ailerons. The directions call for 6 drops of ca per side of hinge. I used about 8 or 9 per side to try to stiffen up the aileron. I read that a stiffer control surface is better. I have heard that some folks have had problems with their hatch coming off in flight. I think the design beautiful but in both of my models the magnets seemed to go too far in the holes. I put a small piece of paper towel in the hole first than the magnet to make it protrude just a bit from the hatch and fuselage. The magnets seem to snap together and hold great. Also a small piece of sticky foam on the top forward part of the hatch to stop the clowl from vibrating and hold the hatch better.
For the engine I used a saito 82a for mine. The only trick I used was to mount the throttle servo facing in towards the fuel tank. This way it was a straight line through the firewall to the engine. The first model I put it on the outside like the directions and made a bunch of bends. Just did not work very well.
Mine balanced about a quarter inch further back than published; about 4" from the L.E. The first one balanced about the same and seamed to fly quite well before it came apart. Anyway, hope this helps those in the future

still no response from GP on the email i sent. granted theyre a big company and i bet they get massive amounts of email...

yo crew cheif! you hit the nail on the head with your post.

and kissel you will be way happier the second time around. keep us posted on your progress. id like to see the counterweights youre thinking of installing.

I was able to get a quick reply from GP by going to their web site GREATPLANES.COM and select the contact us link and than fill out an aircraft comment form. Their response was not great, basically said that you must have screwed up the build and that caused it to crash. They did however reference the setup guide that should of been included in the directions. I than contacted tower hobbys support line and told them of the problem and that GP is somewhat responsible due to not having including this critical guide in the directions. They grumbled a bit and than said to send my plane back to them. I stuffed most of the big bits into a box (it was not pretty) and sent it off. Got an e-mail about a week later that said they did not agree with me and that flutter probably was not the cause but they were going to replace the plane nonetheless. Personally, I did not care what they said so long as they sent me a new one. Don't give up and aside from the 20 or so bucks it cost to ship the pieces back you will get a new one. Hope this helps.....

The aileron mass balance weights I saw on this site http://www.rcuniverse.com/forum/m_91...tm.htm#9193633
I figured, what the heck.....

Too much snow for a test flight, I'll post when it gets airborne. Hope this helps.......

Mark