How to center motor shaft if spinner/prop hole is bigger ? - WattFlyer RC Electric Flight Forums - Discuss radio control eflight

General Electric Discussions Talk about topics related to e-powered RC flying

How to center motor shaft if spinner/prop hole is bigger ?

Old 08-18-2008, 04:02 AM
  #1  
747
Member
Thread Starter
 
747's Avatar
 
Join Date: Sep 2007
Location: Downingtown PA
Posts: 240
Question How to center motor shaft if spinner/prop hole is bigger ?

HI ALL!
I have a EP Rascal 40.
The hole in the plastic spinner base plate and the hole in my Prop have been reamed before (for a different plane) and both have holes slightly bigger than the Motor 's shaft . [The collet nut squeezes this behind as the prop is tightenned].
How do I ensure that when I tighten the prop nut, the prop and spinner-base are at exact center of the shaft's axis? They kinda "hang" when tightenned side ways. I cant tighten vertically for sure.
Do I have to make the holes smaller somehow or place them so that the shaft looks centered and tighten?
Pls advice ....TIA
--747
747 is offline  
Old 08-18-2008, 08:21 AM
  #2  
Ben D wing
Member
 
Ben D wing's Avatar
 
Join Date: Dec 2006
Location: U.K.
Posts: 263
Default

There is no SAFE way of achieving what you ask. IMHO you should buy a new prop and spinner.
Ben D wing is offline  
Old 08-18-2008, 08:43 AM
  #3  
CHELLIE
Super Contributor
 
CHELLIE's Avatar
 
Join Date: Oct 2006
Location: Hesperia, So. Calif
Posts: 19,246
Default

Originally Posted by Ben D wing View Post
There is no SAFE way of achieving what you ask. IMHO you should buy a new prop and spinner.
Yes I agree with Ben D Wing, Its a lot safer to to just get a new prop and spinner, they are Cheap enough, and there is no sence in getting hurt, for a few dollars, We want to keep you around Take care, Chellie
CHELLIE is offline  
Old 08-18-2008, 09:49 AM
  #4  
marchino61
Member
 
Join Date: Apr 2007
Location: Perth, Western Australia
Posts: 261
Default There is a way

If you have a drill press, you can drill the hole out larger and then use an adapter (many props with larger holes come with sets of these adapters) to reduce the hole back to the correct size.

Not sure about the spinner back plate as I am not entirely sure what that is.
marchino61 is offline  
Old 08-18-2008, 04:10 PM
  #5  
buzzbomber
Matt Smith
 
buzzbomber's Avatar
 
Join Date: Jul 2005
Location: Newton, NJ
Posts: 563
Default

In 1/2a nitro engines, we have run into this problem a lot. If we didn't come up with a solution, we wouldn't have been able to use spinners with most Cox, etc engines. The APC props made for 1/2a engines had this problem as well. What we usually did was slip a length of small silicone fuel tubing over the prop shaft and cut it to about 1/16" longer than the thickness of the prop hub and spinner backplate. This keeps the prop and spinner centered just fine in my experience. The other option is to find brass tubing of the appropriate inner and outer diameter, sometimes layering more than one piece was necessary, and cutting it to the thickness of the prop and spinner to use as a bushing.

I suppose these methods are probably considered unsafe nowadays, but they worked fine for many modelers before my time and were the only way to get props to fit some engine/motor shafts up until the electric explosion made a LOT more products available to us a few years ago.

Bottom line, get a new prop and spinner to be on the safe side, but if you like tinkering and are responsible enough to determine whether or not my suggestion will work safely in your application, give it a try.
buzzbomber is offline  
Old 08-18-2008, 07:46 PM
  #6  
eflight-ray
Member
 
eflight-ray's Avatar
 
Join Date: Oct 2005
Location: South Wales, UK
Posts: 562
Default

More than once I have wound layers of masking tape on a shaft to match the hole on a prop, the models have survived, plus I have survived, and I will do it again if needed.

But then I also balance all my props whatever size hole they have.

Occasionally one of the APC prop rings will do the job even on non APC props.
eflight-ray is offline  
Old 08-19-2008, 04:41 AM
  #7  
747
Member
Thread Starter
 
747's Avatar
 
Join Date: Sep 2007
Location: Downingtown PA
Posts: 240
Default

Originally Posted by eflight-ray View Post
But then I also balance all my props whatever size hole they have. .
Thats another thing , how do I balance props correctly...is there a site/thread you can point to ?
747 is offline  
Old 08-19-2008, 09:00 PM
  #8  
Dereck
Super Contributor
 
Join Date: Oct 2005
Posts: 1,071
Default

I use electricians' tape, stripped to needed width, and carefully wrapped around the prop driver shaft until it fits.

This terrifying method has done me fine on lots of stuff, from itty-bitty parkies to 500W+ - have even used it to centre props, never mind spinners.

It's not so much the cost of a spinner / prop / whatever - it's the PITA of digging up who sells whatever, online ordering, sitting and waiting, paying for shipping. Yes, I would cheerfully go to a well stocked and friendly hobby shop...

Regards

Dereck
Dereck is offline  
Old 08-20-2008, 04:56 PM
  #9  
eflight-ray
Member
 
eflight-ray's Avatar
 
Join Date: Oct 2005
Location: South Wales, UK
Posts: 562
Default

Originally Posted by 747 View Post
Thats another thing , how do I balance props correctly...is there a site/thread you can point to ?
You do need a proper prop balancer, either one of the commercial ones or make one yourself, the best is probably the type suspended between two magnets, it gives minimum friction.

To balance, I generally put self adhesive tape on the back face of the tip of the lighter blade, or use something like a clear varnish.

Only if a prop is way out of balance, (very rare), do I cut any off the tip of the heavy side.

If you do a search on 'prop balance' you should find plenty of info.
eflight-ray is offline  
Old 08-21-2008, 01:15 AM
  #10  
747
Member
Thread Starter
 
747's Avatar
 
Join Date: Sep 2007
Location: Downingtown PA
Posts: 240
Default

If I hold the plane down and rev it up , will I notice if the prop is out of balance?
747 is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
embie
Beginners
4
05-23-2008 12:05 AM
fr4nk1yn
Power Systems
1
02-01-2008 01:45 PM
kf6gub
Power Systems
2
09-02-2007 09:00 PM
diverdon
Power Systems
4
06-22-2007 04:26 AM
RSS Feed
RCU RSS Feed
1
02-13-2007 11:06 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Quick Reply: How to center motor shaft if spinner/prop hole is bigger ?


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.

Page generated in 0.06781 seconds with 12 queries