Bent Motor Shaft

[God mode restorations]

Colchester loved using springs and ball bearings.

If you’ve ever opened up one of the handles on their lathes... three balls, three springs, under high tension friction fit... pew pew pew

Still not sure how I fitted them back together, or found them for that matter!

There is a simple method for putting them back together

 

[Dieselman 63]

The handle on the topslide of my Chipmaster I'd wedged on with a bit of paper after a spring and two balls went to explore the abyss.

The Bantam shares the same carriage, cross and compound slides, and tailstock.

You understand

 

[Dieselman 63]

Anyway I think the first job is to rescue the housing. I need to get that off the bent shaft. It’s a good motor and an interesting design.

Has an interesting logo too, BTH for comparison (they were the same company at this point, post 1926)

 

[Parm]

See you’re doing things the sensible way. And you’re actually *trying* to get it to bend. You need to want it to stay straight like your whole project depends on it, only then do you get that shower of swear words and more importantly, a bend!

You must be special.

 

[Pete.]

Motor shaft is easy enough to bend if you drop it as there's a lot of mass in the rotor.

 

[Dieselman 63]

You must be special.

Please refer to my opening line

 

[Seadog]

 

[Pigeon_Droppings2]

With stuff that spins it's balance that's important. If you could check the shaft is still balanced after you straighten it then you'd "probably" still be OK I reckon.

The main problem when it's out of balance is when it spins up that large core mass will will result in force on the bearings which could quickly destroy them.

 

[Dieselman 63]

May I reiterate the lack of bearings here...

Strange woolly mass soaked in oil, plain bored in the housing

 

[MattF]

May I reiterate the lack of bearings here...

Strange woolly mass soaked in oil, plain bored in the housing

PD2's point is still valid. Obviously not in regard to knacking bearings, but it'll vibrate, walk etc. if the balance is out.

 

[Pigeon_Droppings2]

The "bearing" is basically whatever holds the shaft. I think if your "bearing" is basically just a hole in the casing then the balance of the shaft is even more important. I'm surprised there isn't a bush pressed in the casing...I've seen that before.

I did the calculations for a turbo shaft and the forces are surprisingly high...your motor is alot slower than a turbo of course...but it's also alot heavier.

 

[Dieselman 63]

The "bearing" is basically whatever holds the shaft. I think if your "bearing" is basically just a hole in the casing then the balance of the shaft is even more important. I'm surprised there isn't a bush pressed in the casing...I've seen that before.

I did the calculations for a turbo shaft and the forces are surprisingly high...your motor is alot slower than a turbo of course...but it's also alot heavier.

Of course, though a removable bearing end-housing would be easier to remove. I found a stamp on it which said ‘42’ in a circle, I wondered if it was a wartime measure to free up ball-bearings for more critical components such as engines.

 

[eSCHEn]

I've got an old motor here that was given to me for a lathe @Dieselkid 63, I was going to say you are welcome to it for the postage but checking that out you're talking 160NZD to ship it!

 

[Dieselman 63]

Got a picture and specs?

 

[MattF]

The "bearing" is basically whatever holds the shaft. I think if your "bearing" is basically just a hole in the casing then the balance of the shaft is even more important. I'm surprised there isn't a bush pressed in the casing...I've seen that before.

Good point.

 

[500e]

When I was an apprentice we pulled a lot of motors for service both AC & big DC units never seen hairy bearings & this was in the mid 50s there were a lot of 20\30s units about

 

[eSCHEn]

Got a picture and specs?

Of course! I'm no motor tease

 

[Dieselman 63]

Of course! I'm no motor tease
View attachment 173171 View attachment 173173 View attachment 173172

That’s only a third of a horsepower!

I need 2hp ideally. Thanks anyway

 

[eSCHEn]

That’s only a third of a horsepower!

I need 2hp ideally. Thanks anyway

No problems mate.

 

[Dieselman 63]

Check out this massive beast I got the other day. Too big for the lathe even... and only one horsepower.