Printer head starts printing too high

Avac

Cura raises the z axis to 15 mm before moving to the print place (to prevent scratching I think). Unfortunately, Repetier Host does not count this so my skirt/raft/brim is always 15 mm above the bed (this creates a lot of problems lol). I am using Cura separately and the start G-code is:

;Sliced at: {day} {date} {time}

;Basic settings: Layer height: {layer_height} Walls: {wall_thickness} Fill: {fill_density}

;Print time: {print_time}

;Filament used: {filament_amount}m {filament_weight}g

;Filament cost: {filament_cost}

;M190 S{print_bed_temperature} ;Uncomment to add your own bed temperature line

;M109 S{print_temperature} ;Uncomment to add your own temperature line

G21 ;metric values

G90 ;absolute positioning

M82 ;set extruder to absolute mode

M107 ;start with the fan off

G28 X0 Y0 ;move X/Y to min endstops

G28 Z0 ;move Z to min endstops

G1 Z15.0 F{travel_speed} ;move the platform down 15mm

G92 E0 ;zero the extruded length

G1 F200 E3 ;extrude 3mm of feed stock

G92 E0 ;zero the extruded length again

G1 F{travel_speed}

;Put printing message on LCD screen

M117 Printing...

Is there any way to move the extrude head down so I can actually print?

Maybe comment out the G1 Z15.0 F{travel_speed} ;move the platform down 15mm (this might result in the tape tearing on my bed...), or could I write code after it saying move down 15 mm after (if I were to do so, what would the g-code be?)

Avac

I am leaning towards writing a new line of g-code to lower the head by 15 mm. What and where would I write it?

Avac

Ok, I typed G1 Z0 at the end of the g-code, it works, but because I forgot that it was the beginning g-code, all it did was go up, then down. Then I tried sending an M114 at the end, that didn't work, so I just got rid of the G1 Z15... working, but hopefully my extruder head doesn't break.

Repetier

I'm wondering why curaengine does not set z correctly for skirt.

One othe rreason I set Z15 is to not heat on bed (I have a buildtak and that would melt if I heat with long contact). But I never experienced a missing z move at the beginning. After all curaengine needs to go to first layer height afterwards and then starts printing skirt.

Avac

I am using Cura separately, is that a problem?

Avac

My printer always heats up before doing anything (such as homing). Does anyone know the melting temperature of a bed made of Bakelite, aluminum, PCB, glass?

Avac

The g-code displayed when I print starts with:

M190 S70.000000

M109 S190.000000 (not start g-code)

;Sliced at: Sun 28-02-2016 17:42:27

;Basic settings: Layer height: 0.2 Walls: 0.8 Fill: 20

;Print time: 17 minutes

;Filament used: 1.282m 3.0g

;Filament cost: None

M190 S70 ;Uncomment to add your own bed temperature line

M109 S190 ;Uncomment to add your own temperature line

G21 ;metric values

G90 ;absolute positioning

M82 ;set extruder to absolute mode

M107 ;start with the fan off

G28 X0 Y0 ;move X/Y to min endstops

G28 Z0 ;move Z to min endstops

G92 E0 ;zero the extruded length

G1 F200 E3 ;extrude 3mm of feed stock

G92 E0 ;zero the extruded length again

G1 F7800

;Put printing message on LCD screen

M117 Printing...

Instead of this, edit the start g-code to this (will this also get rid of the first two lines for temp?):

;Sliced at: {day} {date} {time}

;Basic settings: Layer height: {layer_height} Walls: {wall_thickness} Fill: {fill_density}

;Print time: {print_time}

;Filament used: {filament_amount}m {filament_weight}g

;Filament cost: {filament_cost}

G21 ;metric values

G90 ;absolute positioning

M82 ;set extruder to absolute mode

M107 ;start with the fan off

G28 X0 Y0 ;move X/Y to min endstops

G28 Z0 ;move Z to min endstops

G1 Z5.0 F{travel_speed} ;move the platform down 5mm

<div style="box-sizing: border-box; font-family: 'Open Sans', Arial, serif; font-size: 16px; line-height: 22.8571px;">M190 S70 ;Uncomment to add your own bed temperature line

M109 S190 ;Uncomment to add your own temperature line

G92 E0 ;zero the extruded length

G1 F200 E3 ;extrude 3mm of feed stock

G92 E0 ;zero the extruded length again

<div style="box-sizing: border-box; font-family: 'Open Sans', Arial, serif; font-size: 16px; line-height: 22.8571px;">G1 Z0.0 F{travel_speed}

G1 F{travel_speed}

;Put printing message on LCD screen

M117 Printing...

</div></div>

Avac

Ok, I have narrowed the problems down, I don't know why, but Repetier-Host is not reading the Z0.300:

;LAYER:0

M107

G0 F7800 X98.985 Y89.214 Z0.300

Also, is there a way to stop Repetier-Host from inserting a temperature command and instead, manually insert one through the start g-code?

Avac

Repetier host doesn't change Z to 15 even though the g-code tells it to, and the firmware also says Z15. I tried adding M114 in pretty much all spots and Repetier host still displays .3 (height of first layer)

Avac

I am just making a new line with M114 in the G-code. This doesn't work, but if I pause the print, and type M114 manually, it works. Is there someway to put this into the starting g-code and where?

Avac

Ok, this is strange...

This is my g-code:

;Basic settings: Layer height: 0.2 Walls: 0.8 Fill: 20

;Print time: 6 minutes

;Filament used: 0.52m 1.0g

;Filament cost: None

G21 ;metric values

G90 ;absolute positioning

M82 ;set extruder to absolute mode

M107 ;start with the fan off

G28 X0 Y0 ;move X/Y to min endstops

G28 Z0 ;move Z to min endstops

G1 Z5.0 F7800 ;move the platform down 5mm

M190 S70 ;Uncomment to add your own bed temperature line

M109 S190 ;Uncomment to add your own temperature line

G92 E0 ;zero the extruded length

G1 F200 E3 ;extrude 3mm of feed stock

G92 E0 ;zero the extruded length again

G1 F7800

;Put printing message on LCD screen

M117 Printing...

;Layer count: 13

;LAYER:0

M107

G0 F7800 X96.009 Y72.749 Z0.300

;TYPE:SKIRT

G1 F1800 X126.239 Y73.955 E1.50938

So in this case, the printer does not lower to .3 as it should, and it also goes faster than what I told it to go (50 mm/s) for the first several G1 commands. If I add an @pause either on top of under the TYPE:SKIRT line, it works :) the printer goes down to z=.3 and the speed is at 50 mm/s. I don't know why this works, but it works.

Repetier

M114 has no effect on the host whileprinting. This is because we send gcodes ahaid so we send more then firmware executed and that would mess up things. This is also why you might not see Z15 in host if we already send the Z0.3, that is no error.

If you enable commands in log window you see what host really sends to printer. How it is interpreted is an other thing. The command it self looks good from here if there are no hidden chars, but why should there be some.

Avac

That makes sense if I am interpreting it correct, but why does @pause make everything work?

Repetier

Pause moves so that might be a point.

Have you tried sending

G0 Z0.3

by hand from manual control`? Whould also work. I can only assume that the combination wit x and y makes the move maybe invalid and then it is skipped. On the other side you are already down at 5mm right? And the coordinates are also inside printer area I guess.

Avac

When I send manual commands/controls, I always pause before I do so, so I am not sure if it works. I'd rather add an @pause because it is easier, and I can clean off extra molten filament. Isn't G0 the command to go straight to the point? When I add an @pause, its like G0 F7800 X96.009 Y72.749 then G1 Z0.3. The z axis is at 5 mm at that time and the coordinates are inside the printer area.

Repetier

Yes G0 goes to the point. @pause stores old position (or what host thinks it is) and goes to that at the end, which is why it works for you as host thinks it is 0.3. Only the mixed command with x,y, and z seems to make a problem for you.

Avac

Do you have a solution for this?

And also, will turning on ping pong help? (I have a Mac)

Avac

It seems as if the mixed command doesn't work only when applying a skirt/brim/raft. Also, it appears that turning ping pong on fixes the problem :) Is it because the mixed G0 command took some time?

Repetier

Ping pong should have no effect on it. It only waits for each command to get an ok.

For the mac I advice to use our new Repetier-Server. It has already more features and works better. It's main feature missing is a slicer and that will come also this year. Until then just use external slicers and upload the gcode to the server to print.