Any advice on how to remove the bell part from a GE bell oscillator from 1928

[David A Cherry]

A fan came in and I should’ve known better, but it had a story attached to it where it was her grandmothers fan, and she wanted it restored.. anyway, I fell for the story and said OK and now I have a dilemma.. the bell is made out of pop metal and was pressed on and I didn’t know it.. now I need a new bell and of course they’re pressed on and people can’t get them off without destroying them.. so my question is, has anybody messed with replacing a damaged bell with a good one successfully?..   any tricks of the trade..  I talked to Paul Graves and he doesn’t see a way without destroying everything..  

[Paul Michael]

Make a multi-piece form to re-'cast' the bell in place. It'll be a b*!›¢ but should be do-able. 

Not the answer you're looking for, but that's one of the projects I have lined up here . . .  I'd be happy if you did it first. (-;

[John Landstrom]

I’ve done it successfully a few times, albeit with a broken gearbox I didn’t care much about.  
The bell is pressed onto a splined shaft.  You’ll have to remove the gearbox from the fan.  Careful, they tend to swell over time and can be a bear to remove without breaking.   If you get that off great!  (If not you can try my method but you’ll have to turn the motor upside down and secure it in some fashion.  
Remove the cover and internals (careful, be sure to remove the small set screw on the large brass alignment bushing side before removing it or you’ll destroy the threads.  The set screw is below the cover screw on that side.  (Same hole)  It takes a very small slotted screwdriver.  

I used a piece of PVC pipe large enough to go around the vertical trumpet shaft on the inside of the gearbox.  The pipe was long enough to allow room for the vertical shaft to completely be driven out of the bell.  Resting that pipe on a solid surface (or captured in a vice) with the gearbox inverted (trumpet on top upside down) I simply used a small punch and tapped lightly until I nudged the shaft out of the trumpet.   Use the dimple you’ll see on the ending the shaft for your drive point.   I have used a penetrating oil as well.   Whether or not it did anything I don’t really know.    
 

If that’s your fan pictured, the bell looks fine, although slightly at an angle.   Is the bottom of the gearbox above the bell damaged?   
 

Putting a new bell on is the easy part, once you find someone with a replacement.  (I may know someone, message me if you need one)

Just take the empty gearbox and slip the vertical shaft down into it.   Take your new bell and slip it up onto the shaft.   The shaft should go in just enough to ensure it’s aligned correctly.   I then rested the bell on a piece of wood and tapped with a small hammer.  The one I used was double headed, with one side being brass and the other being nylon.  Just keep tapping lightly until the bell is in place.   You’ll know if you start by looking at the bottom of the original to see how the shaft is from the end of the opening.   
 

Clear as mud?   

 

Edited May 13, 2023 by John Landstrom

[Jared DelOrfano]

The bell on my AOU was completely broken off the gearbox, so this might not exactly fit your situation.

With some advice from John (listen to him, he knows what he is talking about!), I ended up putting a small vise grip around the broken gearbox piece high that the bell was resting on the vise grips. Then, I put the vise grips into a bench vise. After that, I used a heat gun to get the bell up to about 160°F. From there, I used PB Blaster and a small punch, like John said. Jury is most definitely out on whether or not the PBB actually helped, but the heat definitely did.

[David A Cherry]

Wow, thank you everyone.. definitely pays to be a member.. there’s always somebody that has been there and done that.. it’s nice to be able to fall back on their expertise.. the Little hidden setscrew would’ve got me so now I know.. i’m wondering if Louis Liu might not be interested maybe down the road and casting some of these up or at least 3-D printing them.. he could design them to slip fit and have a double set screw locking in place.. again thanks to everyone so far helping me with this I really appreciate it..

[Paul Michael]

David congress. I like that thinking! This is a part that an 'improvement' in a re-cast makes. much sense. There've got to be hundreds with damaged bells out there.

[John Landstrom]

1 hour ago, Paul Michael said:

David congress. I like that thinking! This is a part that an 'improvement' in a re-cast makes. much sense. There've got to be hundreds with damaged bells out there.

Ditto on the gearbox itself, but a very complicated part.   I pinged him and he requested a picture.  Unfortunately I don’t have a good one as an example.   Besides I think it would be far better he have a perfect one in hand to evaluate, along with the internal parts for setting tolerances.  

[Jared DelOrfano]

I have access to a nifty scanner that creates .STL files. If anyone has a good gearbox or crank disk example maybe I can get a good scan of it and creat a 3D printable file. Mine is decent but not pristine.

Also, here’s a diagram of a gearbox from the 1930 GE Dealer’s catalog I found.

Edited May 14, 2023 by Jared DelOrfano

[David A Cherry]

I sent an email off to Louis Luu on the subject matter, so stay tuned we may start printing these in 3-D.. we will definitely need a scan or we could just wing it.. I think the bell doesn’t have to be dead on just very close.. obviously, it’s just a replacement part for all the damaged chipped pot metal ones out there..

[Louis Luu]

24 minutes ago, David A Cherry said:

I sent an email off to Louis Luu on the subject matter, so stay tuned we may start printing these in 3-D.. we will definitely need a scan or we could just wing it.. I think the bell doesn’t have to be dead on just very close.. obviously, it’s just a replacement part for all the damaged chipped pot metal ones out there..

Send me the whole box with the gears.  If possible, remove the grease, that will save me time.  My work is closing down and I have free time on my hand. 

 

I do have a question, were these "bell" ever made in brass?  I heard of brass bell oscillator but they don't look like the type you posted.  More like this:

[David A Cherry]

My understanding is no on the trumpet bell type.. they were all constructive pot metal..

Edited May 15, 2023 by David A Cherry

[John Landstrom]

The brass bells were earlier.   Sure someone will perk up with a “use/change timeline.

[Steve Stephens]

GE's "brass bell oscillator" was made from 1920 through 1924, Forms V, W, AB, AC, and AD.   As shown below the brass bell was ALWAYS painted the same color of the fan body.   Shiny brass bell discs were modified by some owner.   The finish on my 1922 Form AB below seems to change color but that is due to lighting.   The real color, in person, is more like that in the first and third photos.   I replaced the base felt and power cord (neither are like original) but the plug is original and marked GE on the blades.

Edited May 15, 2023 by Steve Stephens
Add information

[Louis Luu]

Steve, is the gear box interchangeable on yours and the bell/trumpet oscillator?

[Steve Stephens]

Louis, the brass bell oscillator gearbox was made of cast iron and the zinc bell gearbox was made of all pot metal so, no, parts are not interchangeable.  The brass bell gearbox is cast integral with the rear motor plate; the pot metal gearbox was attached to the motor with, I think, a press or close fit.

 

I solved the problem of pot metal gearboxes on my GEs that were in excellent condition but selling those models and keeping only those GEs withcast iron parts so, basically, before 1925.    This 1926 Form AE 2 may have been the beginning of my collection back around 1968 when I found it in a shop.   It was so nice and totally original from the felt to the plug and wires that I kept it until a few years ago.  The pot metal gearbox was what caused me to sell it even with no problems with the gearbox but it was time to start downsizing.

 

Edited May 15, 2023 by Steve Stephens

[John Landstrom]

On my AK1/AOU the gearbox slips into the hole on the rear of the motor and is held in place by 3 small screws.  
 

After removing the screws, the gearboxes can a bear to get off because (as I’m told) they tend to “swell” over time and stick in place.  If you successfully remove a stuck one, simply filing around the back circle of the gearbox allows it to slip in easily.   (Been there, done that)

[Louis Luu]

I need a fan with a gearbox for my next drawing project....does anyone have one?  The Kidney box is coming to an end.  Collar cone is already finished.  I also got a nifty program for making gears now.

[John Landstrom]

Do you just need the motor/gearbox/bell or do you really need the entire fan ?  

[Louis Luu]

24 minutes ago, John Landstrom said:

Do you just need the motor/gearbox/bell or do you really need the entire fan ?  

Back motor cover, box, lid and gears, bell....to ensure everything fits together.  I don't mind buying one....just need to know what model.  I want to make one in aluminum, steel, brass if there is a six blade version.  Not familiar with this particular fan.  The box should be easy to draw up since it has flat surfaces along with the bell.

[John Landstrom]

Louis,

I have a 1930 AK1/AOU.  Not sure how many models/years used the same gearbox style.   
I would, if nudged enough I’d be willing to disassemble it and ship you the parts (assembled) you need. 
 

I also have another donor/parts AK1\AOU I could test parts on.  
 

let me know. 

[Louis Luu]

1 hour ago, John Landstrom said:

Louis,

I have a 1930 AK1/AOU.  Not sure how many models/years used the same gearbox style.   
I would, if nudged enough I’d be willing to disassemble it and ship you the parts (assembled) you need. 
 

I also have another donor/parts AK1\AOU I could test parts on.  
 

let me know. 

Can you please test if the parts are interchangeable.  I will paying for shipping both ways.

[Anthony Lindsey]

Here are the zinc bells

[Louis Luu]

25 minutes ago, Anthony Lindsey said:

Here are the zinc bells

Do you have the rest so I can draw and test fit?

[Anthony Lindsey]

I have a complete gearbox and lid but its from a Vortalex.   I have a correct lid but not a gearbox from the 1926- mid 30's which is the one that's always broken. 

[John Landstrom]

16 hours ago, Louis Luu said:

Can you please test if the parts are interchangeable.  I will paying for shipping both ways.

Sorry Louis, the only GE’s I have are both the same so I can’t test interchangeablity. 
 

I’ll be happy to ship it to you as a test bed.   I have found that a later year (40’s/50’s) did fit, but the later one I tried was a damaged one.  
 

Let me know and I’ll box it up for you to evaluate.   I know there are Many folks out there would love a source for these gearboxes.   I wouldn’t mind testing one out on the parts fan I have hanging around.  I just have to find a good rotor.  The one in the donor fan had the worm fear sheared off.
 

Just a suggestion…..

The thread pattern for the gearbox lid brass screw(s) is 8-36. Not sure on the three screws that attach it to the motor, but their probably a GE thread pattern of the day.  My suggestion is to change these to a modern/common thread pattern (like 8-32) so assembly is easier.  
 

Also, the oscillator knob and shaft can’t be removed from the lid.  Not sure if that hampers your ability to reproduce it.