problem with correct positioning of the nozzle

[ex5]

Hi, I'm not sure it's a good idea to ask questions about MMM here, but I've got a problem setting up the printer, and have no idea where to even start with the debugging.

If I understand the manual correctly, the nozzle should get positioned to the screws A, B and C, but it doesn't, here are the positions it gets instead (marked roughly):

Now that I look at it again, it seems like there's some kind of scale applied to the coordinates, but settings don't seem to have anything that looks relevant, here they are:

And the printout of commands (in order of position center, position A, position B, position C):

SENDING:G28 G92 Z0 G90 G0 F1800 Z2.00 G0 F1800 X40.00 Y40.00 G0 Z1.00
SENDING:G0 F1800 Z2 G1 X76 Y50 G0 Z1
SENDING:G0 F1800 Z2 G1 X76 Y81 G0 Z1
SENDING:G0 F1800 Z2 G1 X49 Y81 G0 Z1

Any help, any suggestion would be greatly appreciated

[dhartkop]

Anna, Thank you for your letter. Yes, this is something I am working to resolve. The best solution is to always press the Level-Center button first before pressing the A, B, or C buttons. Let me know if this works. I am going to be sending an update for the software setup by the end of the month once I have figured out this and some other buts. Again, thank you and please let me know if you have any other questions. -David

On Thu, Feb 25, 2016 at 5:29 AM, Anna Sirota notifications@github.com wrote:

Hi, I'm not sure it's a good idea to ask questions about MMM here, but I've got a problem setting up the printer, and have no idea where to even start with the debugging.

If I understand the manual correctly, the nozzle should get positioned to the screws A, B and C, but it doesn't, here are the positions it gets instead (marked roughly):

[image: index] https://cloud.githubusercontent.com/assets/176934/13319561/d90df89a-dbc2-11e5-98fa-c341fb00e6ed.png

Now that I look at it again, it seems like there's some kind of scale applied to the coordinates, but settings don't seem to have anything that looks relevant, here they are:

[image: screenshot from 2016-02-24 20 44 24] https://cloud.githubusercontent.com/assets/176934/13319606/19e21a18-dbc3-11e5-92e8-8f3c466cbbcb.png

And the printout of commands (in order of position center, position A, position B, position C):

SENDING:G28 G92 Z0 G90 G0 F1800 Z2.00 G0 F1800 X40.00 Y40.00 G0 Z1.00 SENDING:G0 F1800 Z2 G1 X76 Y50 G0 Z1 SENDING:G0 F1800 Z2 G1 X76 Y81 G0 Z1 SENDING:G0 F1800 Z2 G1 X49 Y81 G0 Z1

Any help, any suggestion would be greatly appreciated

— Reply to this email directly or view it on GitHub https://github.com/qbit/MiniMetalMaker/issues/1.

[ex5]

Hi David, Pressing Level-Center doesn't help --- e.g. the position of the nozzle when hitting A is the same no matter if the Level-Center was pressed prior or wasn't. Same for B and C

[dhartkop]

Anna, This is interesting, I will be looking into it. Essentially, the leveling process requires the tip to be near the position of each of the screws and just above the surface. It can still be leveled but requires that it be manually driven to the position. Please see if you are able to level it manually. I apologize for the inconvenience. I will see if I can correct the button code and will share it as an update. -David

On Thu, Feb 25, 2016 at 9:34 AM, Anna Sirota notifications@github.com wrote:

Hi David, Pressing Level-Center doesn't help --- e.g. the position of the nozzle when hitting A is the same no matter if the Level-Center was pressed prior or wasn't. Same for B and C

— Reply to this email directly or view it on GitHub https://github.com/qbit/MiniMetalMaker/issues/1#issuecomment-188867223.

[ex5]

Hi David, I've tried levelling the platform manually, but it turns out that the farthest X and Y coordinates the nozzle can reach are not close enough to any of the screws. So the working plane of the nozzle is much smaller than the printing platform.

Here is the position of the nozzle in the X80 Y80 point:

Also, it looks like the nozzle cannot physically reach the Y coordinate of the points B and C: the platform hits the extruder support before reaching it. Given these constraints it seems impossible to follow the levelling instructions, unless I'm not interpreting them correctly

[dhartkop]

Anna, I apologize for the difficulty with this. When you press the home-all axis button, does the tip go all the way down and touch the platform in the upper right corner? (That should have been the first question that I asked.)

I have gone back in and made a new version of the firmware and the printrun buttons. Please download the .zip file of the latest settings here: http://github.com/MiniMetalMaker/MiniMetalMaker

The button Gcode is in the folder MiniMetalMaker-master / GCode_for_buttons / 160227_MMMPrintrunButtons.txt

The extrude tip will not be required to go outside that top platform. It will go to the spots shown in the included picture.

Thank you again for your patience and please let me know if this helps. I am in the midst of re-writing sections of the manual to make things like this easier. Your communication helps greatly. -David

On Sat, Feb 27, 2016 at 10:39 AM, Anna Sirota notifications@github.com wrote:

Hi David, I've tried levelling the platform manually, but it turns out that the farthest X and Y coordinates the nozzle can reach are not close enough to any of the screws. So the working plane of the nozzle is much smaller than the printing platform.

Here is the position of the nozzle in the X80 Y80 point: [image: 20160227_001] https://cloud.githubusercontent.com/assets/176934/13374263/6e3730ea-dd7f-11e5-9132-241118d80944.jpg

Also, it looks like the nozzle cannot physically reach the Y coordinate of the points B and C: the platform hits the extruder support before reaching it. Given these constraints it seems impossible to follow the levelling instructions, unless I'm not interpreting them correctly

— Reply to this email directly or view it on GitHub https://github.com/qbit/MiniMetalMaker/issues/1#issuecomment-189687717.

[ex5]

Correction: the nozzle can reach farther than the point on the image above, but only right after a disconnect. After the 'Position Center' had been pressed, the nozzle movement is constrained to the plane between a point from the above image and zero.

So, my levelling process looked like this:

1. Press Home-all, then Disconnect and Connect again;
2. go as close to A as possible, and turn the screw;
3. Go as close to B as possible and turn the screw;
4. Go as close to C as possible and turn the screw;
5. repeat steps 2 to 4 several times over, until nozzle moves between the three points very close to the platform but without scratching it;

When you press the home-all axis button, does the tip go all the way down and touch the platform in the upper right corner?

Yes, it does

(I'm very new to reprap and tuning mechanical things, sorry)

I'm going to try the latest settings a bit later, and reply with the results

[dhartkop]

Anna, It sounds like you have successfully leveled the platform, which is really the whole point :-) I wonder why the system will not let you manually drive the nozzle for the full extent of the range. I wonder if it will let you once you have zeroed all the axis. Range for manual controls is set inside the Printrun preferences, which you already showed me are correct. Yes, the open source software is a bit cumbersome to use. Let me know other questions as they arise. -David

On Sat, Feb 27, 2016 at 12:21 PM, Anna Sirota notifications@github.com wrote:

Correction: the nozzle can reach farther than the point on the image above, but only right after a disconnect. After the 'Position Center' had been pressed, the nozzle movement is constrained to the plane between a point from the above image and zero.

So, my levelling process looked like this:

1. Press Home-all, then Disconnect and Connect again;
2. go as close to A as possible, and turn the screw;
3. Go as close to B as possible and turn the screw;
4. Go as close to C as possible and turn the screw;
5. repeat steps 2 to 4 several times over, until nozzle moves between the three points very close to the platform but without scratching it;

When you press the home-all axis button, does the tip go all the way down and touch the platform in the upper right corner?

Yes, it does

(I'm very new to reprap and tuning mechanical things, sorry)

I'm going to try the latest settings a bit later, and reply with the results

— Reply to this email directly or view it on GitHub https://github.com/qbit/MiniMetalMaker/issues/1#issuecomment-189705361.