I have an old 12 volt 3 phase model railroad motor that has a dead spot
between two segments of the commutator.How can i fix it because to get a
replacement is almost impossible

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On 12.05.14 3:18, Bob C wrote:
I have an old 12 volt 3 phase model railroad motor that has a dead spot
between two segments of the commutator.How can i fix it because to get a
replacement is almost impossible

Either find the broken wire, or re-wind it.

On Mon, 12 May 2014 01:18:03 +0000, Bob C
m wrote:

I have an old 12 volt 3 phase model railroad motor that has a dead spot
between two segments of the commutator.How can i fix it because to get a
replacement is almost impossible

No experience personally, but arent' such problems usually right at the
end of the wire, in this case where it connects to the commutator.

Is this Lionel? I do have experience with one of their commutators.
Although it was 55 years ago, I remember a lot. Actually what I
remember is that the commutator was a separate part from the motor,
though maybe not every engine was like that.

"Bob C"

I have an old 12 volt 3 phase model railroad motor


** You mean 12volt 3 pole ?

Typically, 12 volt DC motors have 5 poles - with only three, arcing across
the comm segments will be severe with 12V input.

that has a dead spot
between two segments of the commutator.How can i fix it because to get a
replacement is almost impossible

** There may be a short between two segments or such a bad carbon burn on
one that current cannot flow.

Ideally, you need to trim the com by mounting the rotor in a small lathe,
but most times emery paper will do the job - long as the damage is not too
bad.



..... Phil

In article .com,
says...

I have an old 12 volt 3 phase model railroad motor that has a dead spot
between two segments of the commutator.How can i fix it because to get a
replacement is almost impossible

adjust the brushes, after cleaning up the commy!

Jamie

Følgende er skrevet af Phil Allison:
"Bob C"

I have an old 12 volt 3 phase model railroad motor


** You mean 12volt 3 pole ?

Typically, 12 volt DC motors have 5 poles - with only three, arcing across
the comm segments will be severe with 12V input.

Depends.

The model racing cars my dad imported while I was a kid (Jouef) had 3
poles, while the trains, especially the higher class models, had 5
poles, to be able to drive more slowly and smoothly.

Leif

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Husk kørelys bagpå, hvis din bilfabrikant har taget den idiotiske
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"Leif Neland"
Phil Allison:
"Bob C"

I have an old 12 volt 3 phase model railroad motor


** You mean 12volt 3 pole ?

Typically, 12 volt DC motors have 5 poles - with only three, arcing
across the comm segments will be severe with 12V input.

Depends.

** What I wrote is accurate.


The model racing cars my dad imported while I was a kid (Jouef) had 3
poles,

** IME they spend only a faction of the time with 12V applied.

while the trains, especially the higher class models, had 5 poles, to be
able to drive more slowly and smoothly.

** Not the reason at all.

It's easy to get 3 pole motors to run slowly, SCR and pulse controllers have
been doing it for decades.

Back in the 90s, I raced 1/10th scale RC cars on both tracks and a
elodrome - 3 pole motors were the norm with 7.2 V SubC NiCd packs. The
motors lasted quite well.

Add one more cell and the motor life was cut by a factor of about 10, add
two more and the same motor was lucky to last two minutes.



..... Phil

Phil Allison tastede følgende:
"Leif Neland"
Phil Allison:
"Bob C"

I have an old 12 volt 3 phase model railroad motor


** You mean 12volt 3 pole ?

Typically, 12 volt DC motors have 5 poles - with only three, arcing
across the comm segments will be severe with 12V input.

Depends.

** What I wrote is accurate.

What is typical can be depending on many factors, including date.

The model racing cars my dad imported while I was a kid (Jouef) had 3
poles,

** IME they spend only a faction of the time with 12V applied.

while the trains, especially the higher class models, had 5 poles, to be
able to drive more slowly and smoothly.

** Not the reason at all.

It's easy to get 3 pole motors to run slowly, SCR and pulse controllers have
been doing it for decades.

It was also decades ago, i was a kid.



Back in the 90s, I raced 1/10th scale RC cars on both tracks and a elodrome
- 3 pole motors were the norm with 7.2 V SubC NiCd packs. The motors lasted
quite well.

This was in the 70's. Scale 1/40 cars, transformer-driven.

Leif

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Husk kørelys bagpå, hvis din bilfabrikant har taget den idiotiske
beslutning at undlade det.

"Leif Neland = TROLL"

Typically, 12 volt DC motors have 5 poles - with only three, arcing
across the comm segments will be severe with 12V input.

Depends.

** What I wrote is accurate.

What is typical can be depending on many factors, including date.


** What I wrote is accurate, what you are saying is absurd crap.


The model racing cars my dad imported while I was a kid (Jouef) had 3
poles,

** IME they spend only a faction of the time with 12V applied.

while the trains, especially the higher class models, had 5 poles, to be
able to drive more slowly and smoothly.

** Not the reason at all.

It's easy to get 3 pole motors to run slowly, SCR and pulse controllers
have been doing it for decades.

It was also decades ago, i was a kid.

** Try making an actual point sometime - pal.

I know that is very difficult for a retard like you.

Rest of your tripe snipped.



.... Phil

Phil Allison har bragt dette til os:

Typically, 12 volt DC motors have 5 poles - with only three, arcing
across the comm segments will be severe with 12V input.

Depends.

** What I wrote is accurate.

What is typical can be depending on many factors, including date.


** What I wrote is accurate, what you are saying is absurd crap.


The model racing cars my dad imported while I was a kid (Jouef) had 3
poles,

** IME they spend only a faction of the time with 12V applied.

while the trains, especially the higher class models, had 5 poles, to be
able to drive more slowly and smoothly.

** Not the reason at all.

It's easy to get 3 pole motors to run slowly, SCR and pulse controllers
have been doing it for decades.

It was also decades ago, i was a kid.

** Try making an actual point sometime - pal.

If you re-read the original post:

I have an old 12 volt 3 phase model railroad motor that has a dead spot
between two segments of the commutator.How can i fix it because to get a
replacement is almost impossible

The "old 12 v railroad motor" might be so old my points were valid.

Leif


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