Not sure where to start!

[AndyJUK]

I've adopted an i3 acrylic from my partner's son. He got it a couple of years ago but the Z axis was binding so he gave up and it's been sat doing nothing.

I've stripped it down, put it together again and set the Vref on the stepper drivers. Everything now moves as it should.

When I first tried it I forgot to change the printer profile in Cura. I have an Ender 5. I started it printing a Benchy and it seemed to work pretty much perfectly in terms of movement but the quality was terrible.

I then tried again with the Prusa i3 profile and a couple of others. Currently it's set to Prusa i3

Now, it lifts the Z axis up about 5cm, moves to the middle of the front edge of the bed and moves the Z axis back down but only about 4cm. So, instead of printing in the centre of the bed it tries to print right on the front edge and the nozzle is about 1cm from the bed. I then have to wind the bed back down by hand and try again as it doesn't seem to remember where home is for the Z axis even though I save it when I've levelled the bed.

There is no profile in Cura for this exact printer.

Is there a start and end Gcode I can use?

Is there something extra I need to do?

Thanks
Andy

[William]

Sorry, I do n’t understand. Can you provide a video? Here you can upload compressed files.

[GAQ]

Hi AndyJUK,

So this printer is not going to compete with the ender 5, but it should be able to make some nice prints for you.
No, there's no specific profile for the i3 pro within Cura, but I have played with the settings and have mine printing PETG with Cura sliced models just fine.
It would help if you specified the filament material you're using and also the nozzle size (Some are 0.3mm, some 0.4mm )
As for the unusual behaviour as to where your printer starts to try printing - this could indeed be some odd-ball start gcode at the start of your print ? I know for example that the genuine Prusa models tend to have a start gcode to print a line at the front of the bed before printing (I reckon this is to re-prime the nozzle before the print starts in case it's been left oozing out for a while under gravity). They tend to use Slic3r as their No 1 slicing tool.
You know you can just read gcode with any text editor ? - Then make any changes and re-save.
I always look at them with wordpad and can then use the 'find' function to see anything happening at different z layer settings.
I'll happily share my start and end gcode settings with you, but far better if I show you how to read them and then have ones that suit your particular requirements and explain where mine have come from and why they suit me.
Try reading a few of yours - you'll see the start gcode close to the beginning (Naturally !) you'll have to scroll a few lines up from the bottom for the end gcode as Cura adds quite a bit here...
eg...
My last Cura generated gcode file begins as...
*******************************************************************
;FLAVOR:Marlin
;TIME:24943
;Filament used: 17.8866m
;Layer height: 0.2
;MINX:42.14
;MINY:48.821
;MINZ:0.3
;MAXX:137.138
;MAXY:138.68
;MAXZ:53.7
;Generated with Cura_SteamEngine 4.6.1
M82 ;absolute extrusion mode
********** ALL the above was written by Cura, MY 'Start gcode' begins now..... ******************
G21 ;metric values
G90 ;absolute positioning
M82 ;set extruder to absolute mode
M107 ;start with the fan off - (Aside, I should maybe have M106 S0 here... same thing, set fan speed to zero )
M104 S245 ; set extruder temp (I'm printing with PETG, this is the 'Initial layer' extruder temp)
M140 S75 ; set bed temp (See above ! - This is 'Initial layer' bed temp)
M190 S75 ; wait for bed temp
M109 S245 ; wait for extruder temp (Aside - I generally pre-heat the nozzle and bed and leave for a while to settle down, so this bit is quick)
G28; Home Axis
G29; Z-Probe the bed. (I have a BL Touch fitted, I use this code to probe the bed for self levelling)
G92 E0 ;zero the extruded length
M117 Printing...;Put printing message on LCD screen
**********************************************************************************
Below is the start of the component gcode...
G92 E0
G92 E0
G1 F1800 E-3
;LAYER_COUNT:268
;LAYER:0
M107
... etc etc etc - this goes on for hundreds of lines...
My end gcode is as below...
G92 E0
G1 E-5 F300 ; Retract the filament a bit before lifting the nozzle.
G91 ; set to relative positioning (I'm going to lift the nozzle to 'Where it is now' + 5 )
G1 Z5 ; raise Z 5mm from current position (I have a better way of doing this with variables in Slic3r)
G90 ; set to absolute positioning
G1 F1000 ; re-set travel speed from 300
G1 X20 Y180 ; Almost home X axis and push bed forward to access print.
M104 S0 ; turn off extruder
M140 S0 ; turn off heatbed
M106 S0 ; turn off fan
M84 ; disable motors
M82 ;absolute extrusion mode
**************************************************************
Cura adds about a page of data info below this...

If you were using wordpad to read the gcode, you could use the 'Find' function to look for M104 S0 (That's a zero at the end)
Nowhere else in the gcode will it turn off the extruder heater until it's finished...

Now, I could say that I tend to draw a skirt, 3 laps around and about 8mm from all my prints... This primes the nozzle and lets me see it's printing OK before I waste time should something be amiss ! My Printing gcode will start with this circuit at Z 0.3, found in Cura Layer zero... (Cura starts with zero - I'd start with layer one !) I'm printing PETG with a 0.4mm nozzle, hence I've set my initial start layer at Z = 0.3mm, subsequent layers at +0.2mm each.

Have a look at your gcode and see if there's something lifting the head for no good reason...
Let us know how you get on.
Gerry