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Discussion Starter #1
Back in April, after 50 + years I begin renovating my American flyer train set. I was very naive and learning as I go. I purchased an American flyer 332 and try to run it with my AC transformer not realizing it had a DC motor.I don't remember whether I saw smoke or not but probably did and turn the power off immediately. I was informed I would need to put a bridge rectifier between the transformer in the track. I purchase a 6 amp bridge rectifier. The local ran but did not have much power. I was informed that the 6 amp rectifier was not powerful enough so I purchased a Dallee 1400 e unit. ouch! The train ran better but not great. BTW this was all before I joined this forum. Upon reading Claikens April 25th 2015 thread on his 332 motor issue I realize what I might have done. I recently disassembled the motor and notice the commutator add dimples on the surface. I resurfaced the commutator but the dimples were still there. I did not want to grind the commutator down too far. It also looks like some of the insulation has been melted. Should I grind the commutator down some more and see if that makes a difference or is this motor fried?
 

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The photos aren't really clear, but it looks like the insulation is burned on the windings.

What's it smell like?
 

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The armature face could be resurfaced more but I have to agree with Michael, the windings look burned/melted. So I would guess motor is fried. flyernut could tell you better. You can rewind armature yourself. I have never done one but I know it can be done. I did rewind a field coil, and it works fine. If it were me, I would try to find another armature. Yours does not look good to me. Not sure why AF made DC only motors but they did. Most steamer motors will run on AC or DC. I do not have a DC only so I do not know the difference in motors. I bet many 332s were burned up.
 

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fried but you wont know for 100% sure untill u test each one of them chingaderies for short
 

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The amount of time it takes to damage a DC armature with AC voltage applied is in the seconds, not minutes. It is hard to tell by looking if the armature is bad because the enamel fails in the center before the outer windings fail. There were 2 different DC armatures used in the 332 depending on build date. The early one would read at least 2.7 ohms between any two commutator segments. The later version would read at least 2.1 ohms between segments. Both should be infinite from commutator to the shaft.
The commutator as pictured is not the cause of the poor operation although it could be cleaned up more.
 

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The tricky part is knowing if there are shorted turns. While a shorted turn may not change the resistance much, it will certainly greatly affect motor operation! If that enamel coating is really burnt, I'd be looking for a new armature.
 

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The armatures have either 90 or 100 turns on each pole depending on which version you have. As GRJ says having some of those turns shorted (it does not take very many) causes poor motor performance. It also will run much hotter.
There is about a 10% variation in DC resistance in the factory armatures so finding less than 10 shorted turns with an ohm meter is almost impossible. OTOH if there was 15VAC on that armature for 10 seconds it will read close to zero ohms.
 

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Discussion Starter #11
Did, what is a chingadery and how do you test it. I have an OHM meter where do I place the leads?
 

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I do not rely on testing between segments any more. Reason being my 282 armature
tested good. It wasn't good. All 3 segments tested the same between segments. 1.3 as I remember. My
282 ran at half speed as it should have and motor was getting extremely hot. Very hot.
I tried another armature and my 282 now runs like a hot rod and I can run the snot out of it and it will not even get warm. I did not suspect the armature because it tested good. I bought a running chassis and started changing parts one at a time. The armature change did it.

After the repair I came across 2 brand new armatures from a train shop that had gone out of business. I bought them at a good price.
My 282 runs so good I just left the old used armature in it. So I have 2 brand new armatures. I think many of my AF steamers use this armature. Armatures seldom go bad. Well, unless you use the wrong power. Sorry hjstr6.
 

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If you just want to see if the armature is the problem any AC steamer armature from a 1948 to 1952 engine can be substituted for test running. Be sure to use DC to power the engine! For a permanent repair an armature from a DC motor should be used but it is not absolutely required.
 

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The doohikeys in this case are the 3 segments you see on face of the armature. The way
I think you check them is you hold one probe on one of the segments and then the other probe to one of the other segments. Then try another segment. They should read pretty close to the same. If one is higher, it is shorted. But like I said the test did not work for me.
Best is like I did, change one part at a time and test run. It will not hurt to try the test. Check all 3 segments against the other 2 segments. If one segment shows bad then I bet it is bad.
 

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From my HO days I have a few DC transformers. I have run my AC/DC steamers on
DC power. They ran fine. I really saw no difference in performance.
 

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Most early Gilbert armatures in the universal motors had 75 turns of 27 gauge wire, about 1.4 ohms. The motors were series wired with the 1.5 ohm field giving a total motor resistance of 2.9 ohms. Since the DC motors had a permanent magnet rather than a wire wound field Gilbert made the early DC motor armatures with 100 turns of 29 gauge wire. That is a minimum of 2.7 ohms. For better operation it was later changed to 90 turns of 28 gauge wire for a resistance around 2.2 ohms.
The 1.4 ohm universal motor armature works well in the DC motor, just don't leave the voltage cranked up to max for long term running. Probably more than you wanted to know.
 

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Discussion Starter #20
Mopac and AmFlyer, I tested the commutator segments. Got a reading of 2.2 ohms on all three so I guess I have a later version motor. Also, I have a Dallee 1400 E Unit in the tender, so would it matter if I use AC power with a AC armature? Unfortunately I do not have an AC armature lying around so I would have to extract from one of my existing locos.
 
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