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I would like to add a word of warning when dealing with old transformers:

The 'newest' post-war transformer is now at least 54 years old. It is an extremely  dangerous practice to operate ANY older transformer WITHOUT replacing the 110V AC power cord.  This is not only a fire hazard, but the risk of potentially fatal electric shock with an old, frayed or brittle cord is drastically increased and not something to be easily dismissed.

If you don't have the necessary skills to replace the cord, have a pro do it. But don't ever operate an old transformer with an original cord even if the cord looks 'okay'.

 

Len Carparelli

Dan Padova posted:
RSJB18 posted:

There sure are a lot of taps on the winding Dan. I've never see so many on a small transformer either.

Yes- you have a combination of either constant output which can be varied through the rheostat or stepped voltage in three ranges.

I'd love to open it up and see what makes it tick but I have a feeling that if I do all of the wiring will turn to dust in my hands. Think how well you would move if you were in the same position for 80 years. Add in the heat and its a sure recipe for disaster. 

Here's a better view of the top.

2019-12-24 10.02.00

2019-12-23 18.19.38

Bob

Aren't the casings for these transformers spot welded closed ?

They are not welded and the top can be easily removed after unbending those four tabs that show in the photo.  I have a Type T with the same kind of case in front of me right now.  The solder connections for the line cord are easily accessible.  The secondary wiring is fabric, not rubber, insulated and in good condition.  The line cord needs replacement because the rubber insulation usually is deteriorated after 80-90 years.  Several other such transformers that I've opened were about the same.

I've worked with 90-100 year old locomotives and seen the same wiring results.  Fabric insulation is usually still good, rubber just flakes off.

 

Malcolm Laughlin

The 'newest' post-war transformer is now at least 54 years old. It is an extremely  dangerous practice to operate ANY older transformer WITHOUT replacing the 110V AC power cord.  This is not only a fire hazard, but the risk of potentially fatal electric shock with an old, frayed or brittle cord is drastically increased and not something to be easily dismissed.

The secondary wiring is fabric, not rubber, insulated and in good condition. 

Thanks for the replies and advice Len and Malcolm. I'm a licensed master electrician so I know a thing or two about messing with old electrical equipment . Nice to know the internals are cloth insulated.

When I moved the cord I could hear and feel it cracking. It got one last shot of juice through it. Won't see current again.

Bob

Last edited by RSJB18
Dan Padova posted:

Interesting.  In all the years I've been in this hobby, I have never taken the time to understand those early transformers.  So each contact on the transformer is a step in voltage and the restate is used to make the transition smooth ?

Those transfomers, first sold in 1914, were not developed for use with locomotives with automatic reversing.  Lionel first showed automatic reverse units in its catalog in 1927.  Also in that year, Lionel introduced the No. 81 "controlling rheostat",   It was replaced by the #95 in 1934.  The #95 had a reverse control button instead of the on-off switch.

Before there was automatic reversing, the brief current interruption from moving the contact lever didn't matter.  After that, an external rheostat was needed for continuous current with speed control.

By experimentation, I've learned how to best use one of those transformers with the rheostat.  With that Type B, I would begin with the B-X range.  See what voltage is needed to run your locomotive at the highest speed that you want to see and leave it set for that voltage.  Then use the rheostat to reduce the speed.  It would be a most unusual locomotive that wouldn't stop before you moved the controller so the full resistance of the coil is in series with the motor.  If you can't get a high enough speed with B-X, then go to A-X.  The maximim of 12 volts for C-X won't move any prewar locomotive that I have.

Interesting side note from the 1936 catalog - the 1029 included with Lionel Jr. sets is referred to as a "Speed Control Transfomer".  The older style is called "Multi-volt transformer."

 

RSJB18 posted:

Busy with some last minute shopping yesterday and the kids wanted to bake cookies.....

I did find a few minutes to check the old transformer that came with the set. It still works! The cord is very brittle and will need to be replaced.
The rheostat is neat but it has asbestos wire and a sheet of insulation above the coil so I plan to wrap it up and put it away for now.  Amazing where that stuff was used years ago.

2019-12-23 18.19.49

Those rheostats were made 30 to 50 years before it was suspected that asbestos might be a health hazard and even today it is not harmful unless fibers are inhaled in large quantity of for a long time.  The hardened material in those rheostats is not a problem.  The contact wiper that moves across the metal coil does not come in contact with the insulation.

 

mlaughlinnyc posted:
RSJB18 posted:

Busy with some last minute shopping yesterday and the kids wanted to bake cookies.....

I did find a few minutes to check the old transformer that came with the set. It still works! The cord is very brittle and will need to be replaced.
The rheostat is neat but it has asbestos wire and a sheet of insulation above the coil so I plan to wrap it up and put it away for now.  Amazing where that stuff was used years ago.

2019-12-23 18.19.49

Those rheostats were made 30 to 50 years before it was suspected that asbestos might be a health hazard and even today it is not harmful unless fibers are inhaled in large quantity of for a long time.  The hardened material in those rheostats is not a problem.  The contact wiper that moves across the metal coil does not come in contact with the insulation.

 

Precisely.  The word asbestos creates hysteria needlessly.  

Merry Christmas to all!

Tackled the motor wiring yesterday. Some was still in good shape so I left it in place. The power wire coming from the pick-up was the worst. Looks like the prior owner had issues and used tape to re-insulate it. The stuff was petrified and crumbled off in pieces.

2019-12-24 13.55.112019-12-24 13.55.08

I was able to slide some new insulation over the wire....good as new now. The lamp socket was replaced with new wire. The main coil wire was in bad shape too and received new insulation. The e-unit wires are in good shape.

2019-12-24 14.00.48

Tested the e-unit, still a little sticky but its OK for now.

Finally - I put the armature and brush plate back together. The brushes I thought would fit are too long so I have to order the proper ones.

2019-12-25 11.34.502019-12-25 11.35.10

The motor still needs some tweaking to get it to run but I'm getting closer.

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Videos (1)
2019-12-24 14.56.52
Last edited by RSJB18

It's Alive!

A few days of sitting seems to have done the trick for the motor. I took another stab at getting it running today. I guess the gears were a bit out of sync and the grease had a chance to soak in. Still need to get new brushes but the old ones are working fine for now. Obviously this is the only time this motor will run on 027 curves

Cleaning up the track and a test run are next.

Bob

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2019-12-27 16.09.24

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