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General control line discussion => Open Forum => Topic started by: Dan McEntee on September 16, 2014, 09:25:37 PM

Title: Engine Shaft Extensions
Post by: Dan McEntee on September 16, 2014, 09:25:37 PM

    A friend of mine is building an Umland kit of the Stilletto 660, and for the engine he's using will need a shaft extension. I have to look through my stuff to see if I have any, but I don't think I have ever used one. I know Fox made them and have them on their web site, and will call them at first opportunity. I am unaware of any other manufacturers of this item. Is there an option other than the Fox unit if they are unable to ship any? I think the plans call for a 1/2" extension.
   Thanks a lot,
    Dan McEntee

Title: Re: Engine Shaft Extensions
Post by: bob whitney on September 16, 2014, 09:34:32 PM

what engine is he using

Title: Re: Engine Shaft Extensions
Post by: Paul Smith on September 16, 2014, 10:00:20 PM

Veco made some good ones.

Title: Re: Engine Shaft Extensions
Post by: Steve Helmick on September 16, 2014, 10:06:43 PM

Having used them on a couple of OPP's, I'd suggest avoiding them at all costs...very seriously!  H^^ Steve

Title: Re: Engine Shaft Extensions
Post by: James Mills on September 16, 2014, 10:10:45 PM

Dan,

Sent you a PM and an email.

James

Title: Re: Engine Shaft Extensions
Post by: Chris Wilson on September 16, 2014, 10:51:21 PM

What is wrong with simply using a sleeve nut and thimble made by the nearest and friendliest lathe operator?

Title: Re: Engine Shaft Extensions
Post by: Balsa Butcher on September 16, 2014, 11:21:44 PM

disregard

Title: Re: Engine Shaft Extensions
Post by: Bill Morell on September 16, 2014, 11:41:39 PM

You could ask Charles. He has a lot of experience with them. Seems like he had a unit for sale at one time.

Title: Re: Engine Shaft Extensions
Post by: Chris Wilson on September 16, 2014, 11:55:50 PM

Quote from: Bill Morell on September 16, 2014, 11:41:39 PM

You could ask Charles. He has a lot of experience with them. Seems like he had a unit for sale at one time.

Think that was for a different Stiletto mate.

Title: Re: Engine Shaft Extensions
Post by: RC Storick on September 17, 2014, 12:21:55 AM

Jim Lee makes the best available Bar NONE! If you ask him he will make you a nut to accept the RS spinner. Super cool! I had him make me 2 even one for a PA.

Title: Re: Engine Shaft Extensions
Post by: Paul Smith on September 17, 2014, 06:26:03 AM

A lot of classic-era planes used extensions.  With a Fox 35 Stunt the cowling looks a lot better with the extension.

When I used one I drilled a couple of holes (balanced) through the extension and thrust washer and pegged them together with a couple stubs of 1/16" piano wire. This eliminated the pesky slippage.

Some people (correctly I believe) feel that the added hung load is tough on the plain bearing.

Title: Re: Engine Shaft Extensions
Post by: Jim Svitko on September 17, 2014, 06:36:52 AM

Quote from: Steve Helmick on September 16, 2014, 10:06:43 PM

Having used them on a couple of OPP's, I'd suggest avoiding them at all costs...very seriously!  H^^ Steve

I heard that using the shaft extension causes accelerated wear on the front bushing/bearing.  I can see where that might be the case but I never ran engines with the shaft extension long enough to prove this.

I quit using them, not only due to the possibility of the added bushing/bearing wear, but also other issues such as having to bore out the props, and slippage.

Some nose sections might look better by using the extensions but for me they became too much of a hassle.

Title: Re: Engine Shaft Extensions
Post by: Tom Niebuhr on September 17, 2014, 07:09:28 AM

I used the old Veco shaft extension on Fox 35s for years. I still have a Gold Fox that I used for 5 years when I was practicing almost 40 flights a week. That engine is very worn but is still usable with ABSOLUTLEY NO SHAFT WEAR.

In spite of the more recent complaints about Foxes by people that did not live in the era, Foxes were very reliable. Sure, we needed more power, but that didn't come until years later.

I am sure that  Jim Lee's shaft extensions are quality works of art that will do a great job. Everything that Jim makes is the very best.

One thing of note is that the early engines like the Fox had short shafts. The OS FP and LA engines (.40 and .46) have a shaft that is approx 1/2" longer, so these engines can be used in the Classics without an extension.

Title: Re: Engine Shaft Extensions
Post by: Paul Smith on September 17, 2014, 08:32:19 AM

All very true.

The Fox 35 Stunt was king in the unmuffled era.  They just do not have the excess power or the metalurgy to tolerate a muffler.

Al Rabe using ST 46's and 60's didn't help Fox much either.  Also Lew McFarland with the K&B 45.

Title: Re: Engine Shaft Extensions
Post by: Dan McEntee on September 17, 2014, 11:18:23 AM

  The engine is the current version of the ST.51, and the plans call for the 1/2 " extension to set the engine back for balance considerations and cowl shaping. I never have used them, largely because I don't think I have ever had a model that required one, and I am aware of the need to bore out the center hole on the prop to accommodate the shaft nut, which also has to accept the bolt that holds the spinner on if it is required. I'm ashamed to admit that I had not thought of Jim Lee!! I just don't remember seeing these on his table at contests, but will definitely suggest he give Jim a call.
  And just to round out the search, does Randy Smith offer anything like this? I checked out his website and didn't see anything listed.
  Thanks for the input,
  Dan McEntee

Title: Re: Engine Shaft Extensions
Post by: RC Storick on September 17, 2014, 11:38:09 AM

One on the left is 5/16 threads and 1/4 on the right.

(http://stunthanger.com/smf/index.php?action=dlattach;topic=36667.0;attach=151725;image)

These are set up for RS spinner

Title: Re: Engine Shaft Extensions
Post by: Jim Thomerson on September 17, 2014, 11:53:58 AM

I have several Fox extensions. I'm sure I have a 1/2 inch one.   I have run them on Fox stunt 35s and other engines for years with no problem.  I have also had many happy flights powered by Fox stunt 35 running on muffler pressure. 

Title: Re: Engine Shaft Extensions
Post by: Phil Spillman on September 17, 2014, 07:34:27 PM

Hi Dan, Brodak stocks these and lists them in his catalog. Have your friend call Patty and order one! Their service is stellar and Patty will go and check the stock to be sure while he holds the phone!

Title: Re: Engine Shaft Extensions
Post by: EddyR on September 18, 2014, 04:09:59 PM

I used the fox 3/4 extension on my ST/46 motors for years with no problems. Now I have a lot of props with large holes in them. I used them in many I beam models with fox 35's in them also. Never wore out a shaft bearing in any motor.

Title: Re: Engine Shaft Extensions
Post by: Dan McEntee on September 18, 2014, 04:25:54 PM

   Thanks for all the replies and information. They are easier to acquire than I thought. I know lots of older designsn used them, and I figured junk boxes and spare parts bins all over the country had one or two in them if needed! I haven't had a chance to check my stuff yet, and I probably have one or two. Even boreing the props is no real problem, as Jim Lee make prop bushings, and I can make those also. My only questions was if he needed something special or different, depending on what he's using for a spinner. I'm no where near starting on mine, but what ever we figure out, I'll buy what I need and store it in the kit box!
   Thanks again eveyone,
   Dan McEntee

Title: Re: Engine Shaft Extensions
Post by: EddyR on September 19, 2014, 06:09:03 AM

from 2003

Title: Re: Engine Shaft Extensions
Post by: Steve Helmick on September 21, 2014, 06:45:35 PM

Eddy...Are those Windy U tongue mufflers? I'm asking because I have one on a Big Jim ST .60 "K series". The engine/muffler is available, if anybody has the right $ and wants it...very nice condition, low time.  H^^ Steve

Title: Re: Engine Shaft Extensions
Post by: EddyR on September 21, 2014, 06:57:39 PM

Steve you are correct. That was the only one I had and I sold the plane complete at Brodak.
Ed