Dynamo Video

[GreenTwin]

Here is a channel that I have never seen.

I would really like to make scaled model of a dynamo like this.

Perhaps one day I can get around to casting one of these.

 

[krypto]

https://books.google.com/books?id=NRwZAAAAYAAJ

 

[GreenTwin]

From the above 1894 book, and the same bearing oiler on the 1915 motors that we rebuilt a few years ago.
The ball joint allows the bearing to be self-aligning.
A surprising amount of the bearing shell is cantilevered.
The ball supports all the weight.

No oil pumps required.
The copper rings drag the oil up to the top of the bearing.

These 750 hp motors were rebuilt, and the original babbitt bearings and journals had minimal wear.
The babbitt was beginning to delaminate from the shell, and so was replaced with turbine grade babbit replacement, and a light journal polish.

It took 5 strong people to lift off one bearing shell half.

Makes you wonder how they precision-machined the interior round parts of the bearing support.

 

[Jasonb]

There is a reasonable size dynamo kit available which would save you some time making patterns. I expect the bearing supports could be modified if you wanted the spherical type.

I have thought of an old bi-polar motor along these lines and have one part drawn up. More along the lines of some of the early electric fans than an industrial motor Probably too small for your liking but that casting set from Alyn is a decent size.

 

[Alyn Foundry]

Here’s a few pictures of our Retlas Dynamo being driven by a couple of vintage stationary engines. The armature is from the very popular Lucas dynamo from the 50/60’s. Now being readily available from China. The builder, Denis O’Connell has spent a lot of time embellishing the basic kit to his own satisfaction.

 

[GreenTwin]

That is some beautiful workmanship right there !

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[bluejets]

I would really like to make scaled model of a dynamo like this.

Alternator is much easier and outcome is the same.
One of two I built here around 2 or 3 years ago.

Sufficient information on the original web site for me to reverse engineer the details and cast up the frames etc.

https://www.homemodelenginemachinist.com/threads/model-generator-build-from-casting-kit.33494/

 

[GreenTwin]

Alternator is much easier and outcome is the same.
One of two I built here around 2 or 3 years ago.

Sufficient information on the original web site for me to reverse engineer the details and cast up the frames etc.

https://www.homemodelenginemachinist.com/threads/model-generator-build-from-casting-kit.33494/

Yes, I agree, an alternator would be a better choice.

There is something to be said for the old-school look of a commutator, but I would guess that may be difficult to build ? and with brush wear.

I have seen wound-rotor induction motors, and they are pretty cool looking, and much easier to construct than a commutator.
There would be no funtional reason to build a model motor/generator with a wound rotor, other than it looks old-school, and you could play around with the voltage and current on both the rotor and stator.

This motor is 750 hp, 116 rpm, 695 volts wound rotor at 695 amps, 6,250 volt AC stator, about 84 poles.
This type of motor was used to control inrush current on the stator when starting the motor.
The rotor current is controlled through about 5 steps of resistors, with the final step removing all the resistance.
This is a 1915 Allis Chalmers motor, rebuilt in 2015.
This motor rebuilt shop has their own custom coil winding machines.

The three slip rings on a wound rotor motor would be much easier to make than a commutator, and would last longer too.

I guess I am fascinated with the old school look of these old mechanisms.

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