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Old 03-12-2018, 05:15 AM
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sampojo sampojo is offline
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Join Date: Nov 2010
Posts: 435
My old baldor

Well retired now and a little more time to do things. I have a Baldor industrial DC dual brush 20 pole motor I have been working on and now finished. The commutator design featured reusable spade connectors, whose photos I have posted previously on the thread. Boy did they come in handy as I had to rewire the motor several times. I could not fit enough wire by just lowering it a guage or two from the original 19ga size to get 1ohm of copper wire on it. I calculated the area of the pole gap and the area of the wire plus gaps between round wires, but ended up having to apply a 2.0 correction factor to double the amount of wasted space in a wound coil. I looked into first a quad filar, the a 5-filar 28ga wire to give me the same surface area of the original 19 gauge wire, hoping for more current carrying capacity. As I wound it it looked like it was not going to fill the rotor sufficiently by coil 6. I test wound 24 gauge wire hoping to do a bifilar, but I lost the results. Later I perfected a spread sheet to calculate how many strands of wire were going to be used. If I hadnt lost my test result I would have seen I couldn't get enough wire in again. I got to coil 10 and I could then see it wasn't gonna fit again. So tired of making multifilar wire, and having a better estimate of wasted space, I thought 23 gauge would fit, single strand. But again got to coil 10 and thought it wouldn't fit. So then I did the next 6 coils with my old 5-filar 28ga wire that I saved. At coil 16 it sitll didnt look good and changed to single strand 24 gauge and managed to finish. I always wound in pairs of coils, first coil 1 then coil 11 balancing it with the same wire and wire lay on the coils. Here is my coil winding work sheet and a picture of the rotor.





Assembled





I explored adding an additional brush set to try to tap the coil disconnect BEMF spark energy (red and green wires), but they did not work and just dragged some emf energy out of the system instead. I should probably play with the timing as it is assemble to run in the normal mode.

so pretty much as usual with Ufo Asym motors looks to perform astoundingly better than standard Edison style motors. I have a standard Baldor motor of the same type and hooked them all up and tested both and here is my first results:

Using 24 volts

Standard Baldor rpm 400
Asym Baldor rpm 1400

Now my Baldor I built it to have a 1.1 ohm resistance per coil, instead of the standard 1.0 recommended by Ufo, as I was worried about how hot some of my motors were in the past. But I have checked on the motor magnets, and they seem to hold their magnetism until 400 deg Celsius, or around 700 deg F. So it seems standard magnets will hold and it is no big deal for motors to run at hot to the touch temps, with good wiring and bearings.
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Last edited by sampojo; 03-12-2018 at 05:56 AM.
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