eflite prop mounting
 

I am undertaking a rather ambitious project of building the Guillow's Cessna 170 #302 for radio control and have found this forum to be a terrific source of info. I'd like to lay my plan out there and get comments/critiques/suggestions. I have to order in all the electrics as there is no local hobby shop and would like to make sure I get everything in the order. I already have a JR radio with mini servos. I think this plane will be on the heavy side.

I'll be building the kit pretty much stock but will lighten the balsa where possible - shaving, cutting speed holes in the spars, etc. covering will be tissue and dope. I am going to build it for rudder and elevator control only. I have flown larger nitro planes before as well as smaller, toy-grade foamies.

eflite park 250 brushless outrunner 2200kv
Castle Creations Berg 4l receiver
eflite brushless 10a ESC
450mah 7.2V 25C lipo

from the similar build threads I have read it seems this combo will work quite well using an 8X6 slow flyer prop.

The one thing I haven't been able to figure out is how the prop mounts to the motor???? I'm sure that it will be intuitive once I have them both in my hand but from looking at the pictures of the motor, it seems like something is missing. Is the prop adapter optional - only used if you turn the shaft around as described in some areas? If anyone can provide some info in this regard I would certainly appreciate it.
Also specifically looking for comments on the power/weight ratio for that motor - think it will underpowered? After all, it is a Cessna and I don't think I'll be trying any crazy, high speed, high G maneuvers.

I'll post a build thread as things get going over the holidays here.

RE: eflite prop mounting
 

The motor has a built-in prop saver, and the bearing tube is mounted at the rear.

RE: eflite prop mounting
 

Thank you Dr. Kiwi. So as I understand it, in the outrunners the whole case is what turns so the prop is centered on the small nub at the front in your picture and is held to the motor by elastic bands wrapped around the screws?

RE: eflite prop mounting
 

Yes, if you use the prop saver, that's how it works (surgical tube is good for making O-rings). This motor can also be mounted behind a firewall and the prop attached to the exposed shaft using a standard collet adapter. Here is a review with some more pictures and some performance data which might be useful to you: http://www.rcgroups.com/forums/showt...ht=e+flite+250

RE: eflite prop mounting
 

Thanks again, that was very helpful

Cheers!

RE: eflite prop mounting
 

I've just realized that the E-flite 250 I tested 3yrs ago, and the one which is now available differ in that the "new" one has that exposed shaft sticking out of the bearing tube!

The one I tested could not be mounted behind a firewall.

RE: eflite prop mounting
 

Actually you are correct, it can be done with the new motor. Apparently you can release the shaft, reverse it and reinstall so that it comes out the front and then use the collet or set screw adapters. I have read more than one horror story on the net though about this going terribly wrong and resulting in a broken motor so I won't be trying that.

RE: eflite prop mounting
 

Looking at the photo it seems as if you can use a prop adapter on that motor shaft without altering anything.

RE: eflite prop mounting
 

Well, i have it on good authority that I will be unwrapping one of these on Xmas day ;) and will let you know what I find.:D