Setting up Cartesian Printer.

[dc42]

You can ignore that triangle interpolation message when homing, it's harmless. One of these days I'll fix it.

[Corexy]

Can I change the retraction settings without going through the whole config tool again?

My Z is a direct drive and I understand the factory setting is more like 0.5-1mm at a higher speed.

I understand this can be controlled both by the firmware and the slicer as well? Does the slicer setting overwrite the default firmware setting? Should I just leave retraction at zero, then enter my setting/speed of choice through S3D to suit whatever material I'm printing with?

I'd also like to change the Z probing speed, as the second time I run the config tool I sped it up a little and it's a bit noisier.

I can't find this information in the wiki, what G codes would I be looking for?

[dc42]

Normally people set the retraction in the slicer. On printers with mixing extruders, it's typically better to select "Use firmware retraction" in the slicer and define the settings in firmware instead. If you don't select "Use firmware retraction" in the slicer then the firmware retraction settings are not used.

To adjust the probing speed see https://duet3d.com/wiki/Configuring_RepRapFirmware_for_a_Cartesian_printer#Z_probe_section.

[Corexy]

@dc42:

Normally people set the retraction in the slicer. On printers with mixing extruders, it's typically better to select "Use firmware retraction" in the slicer and define the settings in firmware instead. If you don't select "Use firmware retraction" in the slicer then the firmware retraction settings are not used.

To adjust the probing speed see https://duet3d.com/wiki/Configuring_RepRapFirmware_for_a_Cartesian_printer#Z_probe_section.

Yes thanks, that's what I'll do as it will allow different retraction settings for different materials (recipes) to be saved in the slicer.

Do we have a wiki for setting up the extrusion rate/steps per mm/feed rates for a direct drive extruder?

I emailed you a bunch of questions about speed settings etc (sorry, didn't realize it was Sunday morning there) if you could when you have time.

Had an issue with it refusing to heat, which may have been me firing too many commands at once, and hopefully isn't the mystery issue which keeps blowing mosfets at my house.

[dc42]

You may find this helpful for extruder steps/mm calibration https://reprappro.com/documentation/commissioning-introduction/calibration-duet/#Extruder_calibration. You will need to expand the "More information" heading.

[Corexy]

@dc42:

You may find this helpful for extruder steps/mm calibration https://reprappro.com/documentation/commissioning-introduction/calibration-duet/#Extruder_calibration. You will need to expand the "More information" heading.

That's great. I'll try it tomorrow, thanks as always

[Corexy]

Got the extruder tuned nicely, 122 steps/mm so you weren't far off the money David.

Set my load/unload filament settings accordingly, height, temp, all seems ok.

Tried the test dodecohedron (or whatever it is) and it failed. Too high off the deck and seemed confused in one corner.

I've drawn a simple 50mm cube and tried to slice on the med/0.2mm pla setting in S3D and I'm having a problem.

It's not heating the extruder, only the bed, but still initiating the print when the bed reaches temp.

I've got the primary extruder set as T0, and added the bed as T1. Reversing T0/T1 makes no difference, bed heats only.

I've left all the settings pretty much standard other than to mess with temps/fans over the first 3 layers a bit.

If anyone would tell me what I've got to do to get both bed and extruder to heat before printing, and any other good pla settings for S3D in general, I'd love to get a print off tonight.

Cheers,

and I'm a dumbass as it heats the bed first then the extruder

Looking good but the fans dropped the extruder temp enough to give trouble. I'll slow them right down and try again

[dc42]

You don't need to set up a tool for the bed. Set up tool 0 to be your hot end. You may need to select tool 0 before you start the print, depending on your S3D start gcode.

[Corexy]

@dc42:

You don't need to set up a tool for the bed. Set up tool 0 to be your hot end. You may need to select tool 0 before you start the print, depending on your S3D start gcode.

OK, but if I want to start the bed temp off hotter then drop it a bit can I set it up as tool 1?

[dc42]

There is no need, because S3D lets you change the bed temperature after the first layer anyway,

[Corexy]

I am most certainly not unhappy with this print!

Considering the machine's not completed and I've just used the default S3D medium/0.2 pla menu with a couple of fan and bed temp tweaks, this looks pretty good.

First print failed as I started with no fan for the first layer, then 100% layer 2, which cooled the hot end rapidly.

Next print I set it at 0 for the first layer, 20% second layer and 40% third layer and it's solid as a rock.

Extruder temp 205 first layer then 200 after that and bed 60 first layer then 50 after that.

Haven't even looked at all the other S3D and printer settings because I didn't expect it to print lol.

[Corexy]

Actually printing pretty well.

Possibly a little bit of under extrusion on the top surface, but measured at 49.95mm on both sides, which is nice and close to the files measurements.

Does anyone know how and where I'd add some homing files at the end of the print?

I'd like to drop it to the bottom of the Z axis and home the tool into a corner automatically when the print finishes.

At this stage it just stops with the nozzle still touching the print.

[dc42]

Usually you would put those commands in your slicer end gcode, before the M0 code at the end.

[Corexy]

@dc42:

Usually you would put those commands in your slicer end gcode, before the M0 code at the end.

Really?

I can't have them as a generic command in the printers firmware, that is carried out regardless of the print file I use?

I'd really prefer to do it that way if possible.

[deckingman]

@ Corexy Don't do what I once did. I wanted to drop my bed (same as raising the print head) by 50mm at the end of the print so put G1 Z50 in my end gcode. BUT, I didn't change positioning from absolute (G90) to relative (G91) so instead of dropping the bed 50mm, it tried to raise it to the 50mm from home position. Fortunately, I had reduced the motor current (M906) in a previous line so it just stalled the motor when it sent the printed part crashing into the hot end!

As an aside, dropping the motor current for homing and such like can be a useful tip. I have quite powerful motors and normally run them at 1800 mA but I drop this (and use a slowish speed) to 400mA for homing. Then if an end stop switch or probe fails, the motors are likely to stall before buckling the machine. (Remember to put the current back up at the end though).

[T3P3Tony]

Corexy, most slicers will auto include your start and end gcode files so you only need to set it up once. The advantage of having them in the slicer,especiallly for start gcodes, is that the slicer knows what temperatures you have set so can include the codes to wait while the configured temperatures are reached.

[Corexy]

@T3P3Tony:

Corexy, most slicers will auto include your start and end gcode files so you only need to set it up once. The advantage of having them in the slicer,especiallly for start gcodes, is that the slicer knows what temperatures you have set so can include the codes to wait while the configured temperatures are reached.

I can understand that for the start up (due to the various temps used, plus it's only a tick box on S3D), but I'd have thought that a simple procedure at the end of a print would have been the way to go. Something like:

1. Lower bed to bottom
2. Home tool to desired location
3. Shut down all heaters and drop steppers to 30% current (I realize they will time down and do that anyway).

That's just my opinion, certainly not the only one out there, but if someone could show me the actual lines of code that will do that and where to put them I wouldn't mind try that.

I'd definitely leave the start up for the slicer due to reasons above.

In the meantime I'm getting "spurious heater faults" when trying to heat the bed/extruder right up to try an ABS print.

Should I try 1.15e firmware? I know I haven't got it as the board was sent earlier than it's release.

Thank you all for your replies as well.

[deckingman]

I'll bet someone else will respond while I'm typing this but if not…....

Warning - not tested! Put this in you slicer's end gcode.

1. Lower bed to bottom

G91; set relative positioning
G1 Z300 F240 S1

Set Z to whatever your Z axis travel is, set F to whatever feed rate you use for the Z axis. IMPORTANT set S1 - this flag will check for end stop - if not set, the axis will try to keep moving by whatever amount you set

2. Home tool to desired location.

G90 ; Set absolute postioning
G1 Xnnn Ynnn Fnnn

Change Xnnn to wherever on the bed you want the head to go in X. Zero will send it to the home position but you could send it the right or centres- wherever you want it to be. Likewise Ynnn. Set speed of travel using Fnnn (say 3000)

3. Shut down heaters

Easy way - MO ; tuns off all heaters and motors.

Edit - this will also turn off your hot end cooling fan so maybe not such a good idea as you'll probably want it to run on. So, use the harder way below

Harder way

M140 S0; Turn off bed
M906 Xnnn Ynnn Znnn Enn:nnn:nnn; set motor currents - you'll have to work out what 30% is

You might also like to add M106 S0 ; turn off print cooling fan.

HTH
Ian

[Corexy]

Hey thanks mate, much appreciated.

[deckingman]

No worries. A quick google search of "RepRap start and end gcodes" or some such term will likely throw up some other examples, tips or tricks.