flybyjoe

I have an Ikarus Su27XL that won't go more than three flights with the motor and prop assembly that came with it. I've have received one new prop and the rubber cone that holds it on to the motor shaft, sent me free from the dealer in Fla. but unfortunately, it only lasted three flights as well. I was wondering if anyone else has had this problem and if so, what have you done about it. The dealer offered using CA and some other things, which I had already done on the original and it just doesn't cut it. I even roughed up the shaft a little, to no avail. Nice flying plane and I enjoy it but. . . won't fly without a prop!

Matt Kirsch

What do you mean by "lasted only three flights?" What's happening?

This is a pusher prop plane IIRC, so the prop shouldn't be flying off... As the prop turns its supposed to be pushing it further on to the motor, not pulling it off.

If this is the big SU27, then you should be able to use an aluminum prop adapter, readily available at many "meatspace" hobby shops and online stores. The XXL uses a 400 motor and a standard "Zagi," aka Gunther spoon prop.

Gary Hoorn

Joe,
Please elaborate on the problem. There are lots of us flying this bird without problem. Is the prop slipping on the shaft? Is it coming off the shaft? Need more info in order to be of assistance.
Gary

flybyjoe

Yes, Gary. It spins on the shaft and comes off in the air. I responded to Matt as well.

Gary Hoorn

Joe,
Normally for a pusher prop oriented properly and spinning in the proper directions to spin off the shaft is would have to stall. How much clearance do you have on each side of the prop to the foam? Is the motor mount secure? If all is good clean the prop and shaft with alcohol and use some slow cure CA and shove it on all the way.
Gary

flybyjoe

Gary, thanks for your response and input. I know what you're saying but this particular setting doesn't understand reasoning. I've tried your suggestion and I have no choice but to try it again, and I will. I even cleaned the shaft with acetone the second time. The prop spun off before I could even launch it. Matt or someone made reference to an aluminum application of some kind. I can't visualize it making any difference unless something binds and puts pressure on the shaft. I thought about a square holed washer but then I would have to have a different prop with a much smaller hole. It is possible that I just have a "no go" prop shaft here, or I'm getting the crud of the crop with the prop and spinner "holder oner". I'll probably end up changing the motor with a different prop configuration, even if I have to trim a little out of the deck in front of the prop. Or, Maybe, throw the whole d thing in the burn barrel.

Old Fart

Buy a collet style adaptor.

Gary Hoorn

Joe,
Can you measure the size of the motor shaft? If it is 2mm or larger there are various prop mounts that you can use. It may require cutting away a bit of the foam for clearance but that will definitely solve your problem. Here is where I get some of the adaptors I use.
Gary

http://www.bphobbies.com/view.asp?id=V504514