mniesen89

So I have the 81" from GP, took It out for the 4th flight today, take off was great and no issues for about 5 minutes into the flight.

then, at level flight I see one strut come off and the almost immediately the other come off. My heart just about sunk.....I quickly brought it around for a landing and got it down safe.

After close inspection, I found that the screws where the struts get mounted were to the wing and fuselage were intact and what had actually failed we're the little ca hinges or plastic pieces that make a joint between the long part of the strut and the wood mounting piece that the screw goes through.

Has anyone else had this happen to them? They came from the factory this way, it was nothing that I put together when I received the ARF.

For a GP ARF, this is surely a poorly manufactured plane. There are two other cosmetic flaws that include the balsa under the wing not being sanded under the fabric which looks like rocks are under neath it.

Mikester

My Feedback: (1)

I had the same type of thing happen with mine, seems to be a common problem. I installed some short pieces of woven strapping, like the strapping on some of those small hold down straps you see around, like you would use to strap down a motorcycle on a trailer. The strapping was about 1" or so wide and I was fortunate to have some yellow ones.. I took a Dremel and notched out the strut where the old plastic was and epoxied the new strap in place. I also drilled some small holes through the strut and strap and pegged them with toothpicks. It doesn't look as good as new, but it worked great. We have had two GP Cubs at the field with similar problems. It is a good flying plane and a lot of fun to fly, but the strut connectors are lacking as they come from the factory. I will say that my Cub was about 9 years old when I finally got around to flying it so they had a lot of age on those joints when I had problems. Sadly mine just burrowed in a couple of weeks ago due to a switch failure in flight. Everybody needs a Cub. I hope this will give you an idea of how to repair yours.

bikerbc

I have the same GP Fabric covered Cub and yes you are rite the little CA hinges on the struts are a real weak point...Some guys get replacements from GP but I think unless you need a new strut you are better off too come up with a different fix....Some guys replace the CA hinges with plastic hinges with the cotter pins...You can bolt them into your struts after cutting the CA hinges out....I did that to begin with and it worked great but I had a little accident one day and I dorked my wing ..I replaced my wing and when I did that I made new struts out of streamline tubing..I made little fittings on the ends that screw to the wing and plane...I really like the plane so I didn't mind doing the upgrades that make it a really worthwile plane...The landing gear sucks too...It gave me nothing but grief untill I replaced it with Robart gear...Robart gear is expensive but because I like the plane so much I felt it was worth it...I really like the plane and I bet you will to once you work the bugs out...The struts are probably the biggest bug...They will give you new struts....I am really surprized that they haven't come up with something else after all this time...Those struts have been causing problems for yrs...Yet some guys get away flying them with no problem...Mine failed like yours ,but on the first flight....I was flying off floats and I thought it might have been the extra weight or the water untill I realized lots of guys were having the same failures...Its lucky the wing is strong enough to hold long enough to get the plane back down... If you want I think I could find some pics of the little brackets I made and the streamline tubeing struts ,but for now you are probably better off to just replace the CA hinges with Du-Bro Nylon Hinges 3/4" #257 ..Good luck with this plane..Dont give up on it..It is an awsome plane...I have a OSFS81 on mine..Over powered a bit but I really like the motor..What are you using for power?

mniesen89

Thanks guys for the replies, i surely will do something different.

bikerbc

I think I would call GP Mike...They will probably require proof of purchase but other than that you wont have a problem...Make sure you call and talk to somebody as well as contacting them with your computer ..Okay , I have tried to send a couple of pics...If you need more pics or some better details let me know..I will try and help as much as I can..I am not very good at posting pics..I usually get my wife to help me...She is awsome...

bikerbc

Mikester sorry to hear about the loss of your Cub...Is it repairable or is it going to the big Cub house in the sky ?

mniesen89

Thanks biker, I got the idea, seems like this is what I will do....I'll maybe get some krypton for a cosmetic finish.

mniesen89

So I contacted GP today and no questions asked they are sending  me new struts as well as a new wing. The wing had some major imperfections under the fabric that I complained about....looks like the Rocky Mountains in some areas of the leading edge. I think I'm going to try to beef up the supplied struts and if I don't like how it comes out then ill definitely go with bikers idea

Mikester

My Feedback: (1)

Thanks, but it wasn't worth repairing again. It had several large repairs required while I learned how to properly do a Cub take-off. It went to the great Cub trash can in the garage. I bought a Seagull ARF new in the box from a friend here in town and am now in the assembly process. Thankfully the engine from the old Cub survived with only minor damage.( OS FS 70) I like some things about the Seagull Cub that the GP Cub didn't have. The Seagull has a more scale like landing gear, and a two piece wing. It isn't very scale looking though, has shiny covering. But the quality seems to be pretty good and I think it will look good in the air. I'm sure thinking about a !/4 scale SIG kit though, I've wanted one for years. Thanks for asking.

bikerbc

I dont know if you recall but back when you bought this plane you asked for tips on things that you might be able to do to improve your build and I told you then about your struts...When you get your new wing and struts I would seriously consider re hinging the struts or building a set out of streamline tube or you are going to end up with the same problem...This is really a nice plane and for the life of me I can't understand why they don't fix this problem...

mniesen89

Hey biker, I do recall that and didn't do anything about it. I assure you I will this time!

bikerbc

Yea I bet it is a usual phone call , It kinda makes me think I should have asked for a new wing too...I didn't go for warantee on anything , I just built better stuff but I bought a new wing . The wing was my own fault though...I stalled it on take off... The typical Cub learning curve...I yanked it off the ground before it was ready to fly...That's what I love about Cubs..They teach you how to fly....That GP Cub was my first Cub and its still in pretty good shape so that just proves how tough they must be...I beat the tar outta that poor thing...Did they ask you for proof of purchase or anything? Maybe a person should make a strut kit for that plane and sell it for $100.00...I know that sounds like a lot but I rember the day I made mine it took about 6 hrs....Everybody that sees mine wants a set..They fold up against the wing , they are lite and very strong...I think I could put a few less bolts in them though... Just a thought , when you join your new wing you could put a tiny bit of dihedral in..Maybe 1/2"...If you don't you get a anhedral look... sort of a droop wing...You dont need much , this also allows you to add some wash out if you wish and a little wash out really helps a Cubs manners....

mniesen89

Thanks for the advice.

bikerbc

Yes I Cut them on the band saw...I have a 1/4" fine tooth wavy blade on ... I cut the one end so that it would slip inside the streamline tube about one inch...You can use JB Weld if you want to make it super strong plus bolts....I get my nuts and bolts from Micro fasteners by the hundred so its not so expensive.. The parts that screw to the wing are basically little pieces of angle aluminum Then the part that went into the tubing get cut and shaped so that it hinges on the angle ..Now you make a Y shaped piece that attaches both struts together ..Again You can JB Weld and Bolt it together... The bottom end attaches to the fuselage so it goes together and comes apart every time you go fly... You make the same sort of attachment as is on the wing ..You can either Bolt it together or pin it with one of those little spring clip things...I can take some better pics of the joints if you like...I am sorry I am not very good at explaining things...I have recently had a stroke and I have a difficult with things that require concentration.....It is good for me to try....If you were here I would help you make them..I am lucky because my buddy has a whole bunch of aluminum pieces of all different sizes I can get for free...I am going to try and get my wife to post a few pics when she gets home..It might help show you the pieces I made ...I drew pics of them ....

bikerbc

Okay here are the pics..Sorry they are a bit hard to see...I am not sure why ,glare from the flash maybe...I hope you can make them out okay....If not let me know and I will try again....