I too have build an Edison Bipolar Dynamo so I can appreciate your work. I'll add that I recommend going to the trouble of removing those ball-bearings from the armature so you can make some more Edison-period looking bearings. FYI, I once had to use a slitting abrasive disk on a dremel to do that as sometimes they're a press fit.
To design mine I dusted off my college physics text book and did the math so that it puts out 12-volts at 1200 RPM. anyone that wants to see how to do it just say so and I'll post the formulas here.
I've set mine up on a board with a Stuart No 9, the 1-1/2" bore is a good match for a 1-1/2" armature at least looks wise, and a cabinet with meters on the front and a light bulb in a socket on top.
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Hi - I love what you have done here. It is in the right style for demonstrating the period of DC generation. Please can you explain the brush holder? - as I am "guessing" from what I can see in the photo?
I assume the brush holder rotates around the axis of the armature, so is set such that when the current flows into a segment of the commutator, the poles of the armature are passing from the axis of the poles, towards where the "generating" segment of the armature leaves the poles? I'E. for a particular pair of armature poles, they enter the magnetic field of the poles, and "reluctantly" build up an EMF as the rotation cuts the lines of flux until they reach a maximum EMF - at which point the brushes align and "discharge" the magnetic flux by drawing out the electric current and "de-magnetising" to segments of the armature?
If the poles do rotate around the axis of the generator, have you rotated the brush holder to a "maximum" point where the generator is matched to the speed at which you run the generator? I have figured-out that this angle of "lag" may need to vary to get the optimum for any particular speed? - But my reasoning may be completely ****-eyed! I would like to hear more about this from your experience.
It strikes me that if the brush holder is at the wrong phase angle for the speed and "phasing of the armature windings", then the generator will be "poor" (low current, even if the voltage is OK). - This could be the problem with poor generation after the resolution of any "field and winding issues.
But thinking a bit further: Generator problems may be as simple as "not enough speed" - to develop the voltage. The current will then depend on the ability to maintain that speed and voltage against the load by an adequate current in the field coils - up the the safe limit (which is usually the temperature inside the windings, which, if too hot, causes catastrophic breakdown of insulation, shorting and burn-out of the windings). The "rating" of the insulated wire is "in free air" - not when buried inside a hot coil - so PLEASE watch the field coil temperature. Too "Hot to the touch" is over about 55 degrees and the current needs to be turned-down. (Windings inside th coils will be hotter than on the outside!). If there is insufficient field for the generator at a "comfortable warm" then you simply need lots more windings to get more magnetic field into the generator. - And possibly more neodymium magnets to get it started? The design problem of too many Neodymium magnets is that you can't regulate the generator "down" as low as may be necessary. The remanent magnetism is a "minimum" - which needs to be high enough to start the generation, but low enough the generator isn't doing too much at low load. - The consequence is that the voltage will be too high, so you need to slow the generator. The current in the field coils is simply increasing the field from the "neodymium" minimum to the max that you can get at the field-coil current limit. Check the WWW as I am sure there will be a text book to explain it better than I can( - as a total amateur!).
Another comment: If there is no "initial remanence" of magnetic field in the Pole arrangement, then the generator cannot generate. (A car alternator is initially excited by a small current from the controller until it "kicks-in" - Years ago this was the main purpose of the "warning light" circuit!). I think the neodymium magnets are built-in to the pole assembly to achieve an initial remanent magnetic field for the generator to start. When running, the field needs to be controlled to keep the generator at the correct voltage for the speed and load.