Prusa i3 control problems with Marlin

Hey guys! I'm having a weird problem and, unfortunately, because it is so similar to a different one when I try to search for or google the symptoms, I keep hitting the same dead ends.

I have Marlin installed on a RAMPS/Mega board and everything has gone smoothly through installation and building the printer. However, whenever I try to move the axes using the buttons for manual control in either Pronterface or Repetier Host the motors just whine and do not move. I know, I know, up to this point it sounds like the same "You didn't calibrate your stepper drivers" issue that people come here with all the time, or like a hardware problem.

The thing is, though, that if I just inject raw g code or run the test firmware on it, everything moves just fine. The motors run, everything whizzes back and forth, lights light up, the dead rize, brooms become animate and start flooding the castle... the whole works. I've done the calibration process for the stepper drivers 20 or 30 times a day for the last week, hoping I just did something wrong and this time it will work, but to no avail. I'm starting to think I'm going nuts. Clearly there isn't anything wrong with the hardware.

Any ideas?

Are you sending a speed along with the raw GCode? Perhaps Pronterface is trying to spin the motors too fast, and when you send the GCode manually, you're using a speed they like better.

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm

Thanks AbuMaia, I had this same issue, and your suggestion fixed it. For some reason Pronterface was defaulted to 3000mm/s; no wonder it was having issues.

Although this fixed it for manual movements, when i try to home the setup it still whines/doesn't move. Does homing use a different speed setting for some reason? Or am i missing something else?

That's odd. In my pronterface, speeds are mm/min. 3000 mm/min is 50 mm/sec. Though with Slic3r being mm/sec, it can get a bit confusing testing speed in one and setting it in the other.

Edited 1 time(s). Last edit at 03/30/2014 10:09AM by AbuMaia.

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm