Prop adapter precision ring does not fit - RC Groups
Thread Tools
Sep 29, 2012, 11:23 PM
Registered User
astromog's Avatar

Prop adapter precision ring does not fit

I'm moving into electric flight, but I'm having trouble with propeller mounting.

I have a Hyperion Z22 motor, which has a 3mm shaft. It came with this collet-style adapter:

I'm trying to mount an APC-E 9x6 propeller on it. I bought some Hyperion precision rings to centre the propeller, which the product info claims match the collet I have:

The problem I'm having is that the rings do not fit over the smooth part of the collet's shaft. They slide over the threaded part and stop dead when they hit the smooth part. I assumed it would be a tight fit, or there wouldn't be any point, but this is so tight that it refuses to move over the smooth part at all. If the ring doesn't go on the smooth part, then the propeller itself is not far enough back on the collet shaft to grip the motor shaft strongly. When I tried to use the nut to tighten the ring onto the shaft, I ended up stripping the nut's thread.

I've had the same result using the plastic precision ring that came with the APC propeller.

I can't figure out what I'm doing wrong. There must be something simple that I've missed. Am I supposed to use oil to slide the ring over the shaft? Am I supposed to fill the smooth portion with washers? Should I use a hammer to install it?

I don't want to use a prop saver without at least figuring out why I can't install something that noone else seems to have any trouble with.
Sign up now
to remove ads between posts
Sep 29, 2012, 11:54 PM
222 km/hr Parkjet flyer
solentlife's Avatar
This will horrify the purists .... but I have had similar where shaft is not exactly the size it states.

I use a prop reamer ... the tapered version to open out the adaptor ring to make it a good fit. You cannot drill the ring - too innaccurate. So the best is to ream out.

Tapered reamers are available in DIY shops or LHS ... (better to get a DIY shop / tool shop model as LHS ones tend to be soft metal and cutting edge dulls easily. They can be sharpened with a file ... )

Sep 30, 2012, 12:54 AM
Registered User
I use a round file. Rarely do the little adapters fit until I file them a bit. Never had a problem.

Sep 30, 2012, 06:55 AM
Registered User
ggcrandall1's Avatar
Get a dowel rod or bolt that is a a bit smaller than the hole in the ring. Glue a piece of sand paper around the dowel. Chuck the dowel into a drill and use that to ream out the ring. The plastic ones that came with the prop will be easier to ream out.

Sep 30, 2012, 08:12 AM
222 km/hr Parkjet flyer
solentlife's Avatar
Honest guys - use a tapered reamer. Drills, dowels, they do not self centre.

For the same reason you use a reamer on a prop - the ring is same.

With the tapered reamer - I've opened up EDF rotors, props, servo arms, control horns, screw holes in firewalls, you name it - it provides an excellent self-centering tool.

I found an unusual use for the reamer recently ....... pricking through plans onto Depron / Balsa for cutting. Run along a wing to create a channel to lay your stiffening CF / bamboo into ...

Another use ..... the blade edges are SHARP .... cutting iron-on covering is a cinch with it.

Sep 30, 2012, 09:20 AM
Registered User
tacx's Avatar
If you have a tapered round file thats not too course and is the right size, you can chuck it into a variable speed drill motor and ream the ring that way. You will have to hold the ring with a pair of pliers, but this will work in a pinch. I have done it with good results. The file will center just like a tapeared reamer.
Sep 30, 2012, 10:01 AM
Registered User
FlyBoy20's Avatar
....or you might try just heating it up and doing a shrink fit - if it's only a small clearance, and you don't need to get it off again?

Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Question prop wont fit adapter thebuckeye Electric Plane Talk 10 May 29, 2012 01:03 PM
Discussion props does not fit spinners? pete2194 Power Systems 6 Jan 21, 2007 12:14 PM
Collet Prop Adapters to fit HD Props no stick GWS (Grand Wing Servo) 10 Mar 13, 2006 08:12 AM
What collet prop shaft adapter fits APC SF props? SlowRider Power Systems 9 Dec 03, 2004 09:11 PM
How do you fit a GWS SF prop to a Cobri Prop adapter/shaft? AdrianM 3D Flying 2 Mar 23, 2004 11:17 AM