I have restored a prewar 253 electric and the 613, 613, 614 cars. Naturally, when I ran it, the commutator in the old motor self-destructed. I want to rebuild the armature myself, but am stumped on the winding connections. I am fairly sure there is only one winding connection to each commutator face.
In a forum discussion in Dec. 2005, Bob Nelson commented that each face has connections to (2) windings. Is that the case for all armatures? My 1 95 armature is pretty simple, with each winding connected to the other on one end and to a commutator face on the other, unless I am missing something. (Please, no comments about the rewinding of armature by an amateur. )
Byron in Ohio
There are two connections to each face. One from the coil on each side. Look at a working commutator and you can see for yourself.
Thanks, GRJ.
I looked at the commutator on a prewar 262E with a similar super motor to the older 253, but with a single metal idle gear. That commutator had only one connection visible on each face. Then, I checked a postwar 2025. It had two connections on each face. Both loco's needed attention to their e-units anyway.
I am looking for information specifically on a 1-95 armature used on supermotors with two fiber idle gears. . If I can't find any specific information, I am going to rebuild mine as best I know. If I bed the commutator with a temporary adhesive, I can run the motor and remove the commutator if needed..
copperkettle
Byron, I'm having trouble with your description, "with each winding connected to the other on one end and to a commutator face on the other". Did you mean "with each winding connected to the others on one end...? That is, are the windings connected in a Y configuration, with one end of each of all three connected together? That would be a workable arrangement, but inferior to the usual delta connection. So, if that's what you have, I would rewire it just as it was.
Bob Nelson
I've never seen one wired that way, but I guess there's a first time for everything. :D I actually looked at a couple of old motors in my junkbox, they were all wired in a delta configuration. I thought that's how they all were.
Hi Lionelsoni & Gunrunnerjohn, sorry for the vague description. The windings were connected in a 'Y' at the "start-of-wind" end and connected to a commutator face on the "end-of-wind" end. The 'Y' connection was buried under the commutator. I think that when I rebuilt the commutator after it disassembled, I must have shorted the 'Y' to the shaft or bearing. The engine ran, but with a lot of sparks and overheating. I will connect the new windings the same way (w/o the short).
I gather that the "delta" configuration connects the windings to the commutator faces in series around the commutator. Correct?
Yes.
The "Y" connection typically gives less torque than the "Delta" connection, which is why it's not often seen.
I seem to remember from my High School years in Vo-Tech that the commutator bars need to be correctly oriented to the poles of the armature for it to work correctly.
Something maybe you should look at.
Banks, Proud member of the OTTS TCA 12-67310
Either Y or delta will give the same performance given that the wire sized is correct. Unless you have smoked the wires I would not replace them. It sounds like you have problems with the commutator and maybe the common connection for the Y.
If you do rewind the armature and retain the Y configuration, make sure you use the same wire size. If you make the wire smaller, you will need more voltage and less current from the transformer. If you make the wire larger, you will need less voltage and more current.
BB
Given a 3-pole motor, the delta's coils will all be carrying current all the time, one of them connected directly across the brushes and the other two in series, with the coils reconnected through six series-parallel arrangements during each rotation, so that poles are excited on both sides of the armature. The Y configuration, on the other hand, always has two coils in series and one disconnected. The disconnected coil obviously does not contribute to the torque.
I agree with Banks, that the relationship of the coils to the commutator segments is critical. The best way to get this right is to have noted how it was before and to duplicate it. However, in this case there are only three ways to do it; so trial and error is actually not that impractical.
Wow, thanks for all the information, everyone.
After trying 32 and 30 gauge wire, I settled on 26 gauge wire , one step lower (bigger?) than the 28 gauge used originally and 20 turns less than the 90 Lionel wound on the armature. I rewound the armature 3 or 4 times and rebuilt the commutator at least 4 times before I found that the old hot wire and field wire connections were shorting to the motor frame. After repairing all the loose connections, building a solid commutator and figuring out the "delta" connection. I have the old 253 running cool & quiet. It seems to have all the power it had before. I positioned the commutator as originally located. The radial CL of each facing is positioned at the midpoint of the angle formed by the adjacent windings. I could not measure any 'lead or lag" angle. Seems to work.
I am at a loss as to why a short in the pick-up connection would cause problems that mimic a shorted winding, i.e. noisy, lots of sparks, refusal to run in one direction or the other, HEAT.
As far as he winding operation, I built a winder using a 2 RPM timer motor and a sturdy casting reel for tension. With a little care, it would wind on even, tight turns. The frame was wood, glued & screwed together. I used a small lathe to finish the commutator facings
Sounds like you put a lot of time in on this. How did you hold the armature while winding it?
Hi Banks, Yes I did! My wife thinks it as more, I think it was less. I'll do it again in much less time because I won't need to invent tools or find materials that work.
It seems that the best I can do is to post a picture on my Facebook page. Look for Byron Allen with the Terracotta 253 picture. It's in an album called "armature rewinder". (Very original) the album should be available for anyone to open.
I can try to describe it. I mounted the motor on an 'L' shaped frame and attached the armature fixture to the timer output shaft with a dowel and wooden coupling made from a larger dowel. The casting reel is mounted on a wooden mount at a right angle to the motor-fixture assembly with hose clamps . everything is screwed & glued. The fixture is "U" shaped & holds the armature by the shaft with one jaw fixed and one held by a screw so the armature can be unmounted and removed. The armature is held tight against the back of the fixture so it won't move.
I mounted a pedometer on a wooden arm that drops off a cam to count the revolutions of the fixture. Springs pull the arm sharply to count.
Also, I thought the locomotive was as good as new, however---the locomotive runs slower now, but still will pull its' load of three 613-14 cars. It doesn't have enough torque to spin the wheels when held so it really isn't as good as it was when new.
When you reduced the number of coils from 90 tp 70, you reduced the motor torque by 4900/8100 or almost half. The field created by the coils is proportional to the number of turns squared. Now, with the heavier gauge wire, it isn't quite this bad as there will be some increase in current due to the heavier wire on the armature, but the armature current is limited by the field impedance since this is a series wound motor. The wire size and turns for both the armature and field should be matched to optimize the motor torque. If you do one again, I suggest you stay with the original wire size.
Bruce Baker
Byron,
I tried looking for Byron Allen with the Terracotta 253 but Facebook wouldn't give me fuul list because I'm not a member. Can you post a link?
Hi, Banks. Let's try Flickr. go to
http://www.flickr.com/photos/54020227@NO7/55966898888/in/photostream
I tried to insert a link but couldn't. You can also got to flickr.com & enter "blithe.spirits" in the search window and click on "PEOPLE" I tried it. It will work even if you are not a member.
Byron
Thanks,
Very innovative.
Our community is FREE to join. To participate you must either login or register for an account.
Get the Classic Toy Trains newsletter delivered to your inbox twice a month