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Re: Prusa i3 acrylic extruder problem

Posted: Tue Apr 14, 2015 9:32 pm
by hugues
Did you stick the heat sink to A4988(Perhaps you call it pollolu) .?
Yes, I've sticked heat sink on all the A4988 (Yes, I called it pollolu, sorry :D )
they look like that (except the color)
Image

Re: Prusa i3 acrylic extruder problem

Posted: Wed Apr 15, 2015 10:12 am
by zhangxueyou
hugues wrote:
Did you stick the heat sink to A4988(Perhaps you call it pollolu) .?
Yes, I've sticked heat sink on all the A4988 (Yes, I called it pollolu, sorry :D )
they look like that (except the color)
Image
If you "inverted the pollolu axis E with the one of the y-axis, the y-axis no longer moves, the motor vibrate", the vibrating motor is y motor, I think you should contact the customer service.

Re: Prusa i3 acrylic extruder problem

Posted: Tue Apr 28, 2015 4:05 am
by hugues
Hi.

Good news.
I didn't way for a spare part, I've ordered DRV8825 instead of A4988.
It seem to be more resistant. :)
The only things to do is to keep only the 3rd jumper for 16microsteps and fine tuning the power (warning, potentiometer must be on the other side).
And TADAA! It works.

But there's a problem with the parameters for the extruder.
Esteps are 800 and it is way too high for a direct drive extruder.
I found that mine is working well with E steps = 95.

I can change it in repetier-host (EEPROM configuration) but I guess there is no eeprom on the sanguinololu, so it's back to 800 when powering off or resetting the printer...

I don't want to upload a new firmware because all the other parameters seem ok.

Anyway, I found a solution to get this parameter updated on powering the printer.

I added custom gcode in the slicer.
M92 X80.00 Y80.00 Z2560.00 E95.00 .

And second benefit, I can print with the sd card.

Hope this can help.

Re: Prusa i3 acrylic extruder problem

Posted: Wed Apr 29, 2015 2:23 pm
by vad7
The sanguinololu has EEPROM in the Atmega1280.
You need reflash the firmware to activate it.
Unmark this line in the configuration.h :
#define EEPROM_SETTINGS

Re: Prusa i3 acrylic extruder problem

Posted: Fri May 08, 2015 10:32 pm
by Marchello
I have the same problem. The printer with Sanguinololu board works fine sometimes, but other times the E-motor binds and stutters (as shown in the video by Multipicture) specifically when printing infills.
I tried swapping the A4988 of the E-motor with the A4988 of the Z-motor but this does not solve the problem.
As said: The printer did work fine for a while and it still does except for the bind and stutters of the E-motor.
Please help.

Re: Prusa i3 acrylic extruder problem

Posted: Mon Nov 02, 2015 1:42 am
by frangel
Hi, I just finished assembling my Prusa Geeetech i3, i tested a square part and the movements are fine, but the extruder does not work, it does not click or respond to any command. I checked the connections, tried switching A4988 from x axis with the one for the extruder, nothing changed.

Re: Prusa i3 acrylic extruder problem

Posted: Mon Nov 02, 2015 11:29 am
by Sherry
frangel wrote:Hi, I just finished assembling my Prusa Geeetech i3, i tested a square part and the movements are fine, but the extruder does not work, it does not click or respond to any command. I checked the connections, tried switching A4988 from x axis with the one for the extruder, nothing changed.
Maybe the post is helpful for you.
http://www.geeetech.com/forum/viewtopic ... 13&t=17097