Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 09:15AM |
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Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 10:53AM |
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Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 11:04AM |
Registered: 9 years ago Posts: 49 |
Quote
madias
jnsbanman : There is no need to "tell the board" something, because the z-steppers are parallel connected to one driver output. Just disconnect the secondary z-stepper. If one stepper hasn't enough torque (or too much), you'll need to fine adjust the driver output. But I really see no benefit from this construction, but perhaps I'm wrong (I had never problems with the z-axis on my printer)
Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 11:16AM |
Registered: 9 years ago Posts: 91 |
Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 11:24AM |
Registered: 9 years ago Posts: 49 |
The X axis moves up and down in the Z axis very smoothly. This upgrade even stopped the high pitch whining the lead screws were making when moving up and down.Quote
madias
So you must have the two steppers physically connected - so one stepper is build in on the top of the new thing, and the second stepper is just lying around? Yes it is sitting beside the machine
That's totally strange, only possible thing is, that you really have to adjust the vref of the stepper. So again: "Normally" both z-axis motors are running and if you disconnected one (have you tried to switch them?) the other one won't do anything? Right they will only work when both are connected
Even without connected to the mechanics? Yes even if they are just sitting on the table
I believe that the most problems with the z-axis are jamming parts. If you stiff the x-axis belt the two z-rods were compressed and you have to compensate it with the z-axis rods (stiff the x-axis belt and then pull the two z-rods a little bit apart - both z-axis should NOT building an "O" or a "X"). Best way to do that is without the z-lead-rods connected. The whole x-axis part should slide easily up and down without jamming on any position.
Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 11:45AM |
Registered: 9 years ago Posts: 91 |
Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 11:51AM |
Registered: 9 years ago Posts: 49 |
Quote
madias
Ok, I'm sure you'll have to setup the motor current for the single z-motor (I think the current is much too high, because the driver current was calculated for driving two motors):
[reprap.org]
Connect only one motor and try out different trim poti settings (but stay within v-min and v-max!!!) until the motor runs smoothly. Begin at 0.4V and then turn it up
Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 11:53AM |
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Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 11:55AM |
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Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 11:59AM |
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Re: P802M Prusa i3 Unofficial Support Thread March 07, 2016 12:08PM |
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Quote
madias
If everything went wrong you can just adding some load resistors instead of the second stepper
Re: P802M Prusa i3 Unofficial Support Thread March 11, 2016 07:13AM |
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Re: P802M Prusa i3 Unofficial Support Thread March 11, 2016 02:12PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 11, 2016 02:27PM |
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Mine are (and originally were) 100/100/400.Quote
broy55
OSNWT, thank you for this good information. I also have the leadscrew rods and noticed my prints were coming out too small. Had to change the steps per mm in the firmware from 80 to 100 for X and Y, Z is set for 400.
Not 25'000, but 250'000. The reason is we want faster communications, but ISO standard 230400 rate is not good for 16MHz crystal. That's why non-ISO baud rates: they just have an integer divider for crystal frequency (16000000/250000 = 64, 16000000/230400 = 69.44444444444, 16000000/115200. = 138.8888888889).Quote
I might try changing the baud rate from 115200 to 25000.
No idea, but I think no reason to develop a completely different board. I think it should be compatible.Quote
Now I'm not sure if I have the same melzi board as you but my board is square (not rectangular). Is this board still compatible with Melzi 2.0, and can I upgrade the firmware on it? (see attached photo).
Re: P802M Prusa i3 Unofficial Support Thread March 11, 2016 02:33PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 11, 2016 09:23PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 12, 2016 02:50PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 12, 2016 05:44PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 12, 2016 06:17PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 13, 2016 07:24AM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 10:07AM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 11:19AM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 12:20PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 12:36PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 12:44PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 01:22PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 01:44PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 02:31PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 03:02PM |
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Re: P802M Prusa i3 Unofficial Support Thread March 14, 2016 03:08PM |
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