Thanks for the thorough explanations!

Yes, there are multiple G1 commands between M3 and M5.

However, I think I noticed that with slower speeds my paths are "more complete" - I have to make more tests about that.
I think the picture was taken with 6mm/s.
My initial tests were with 50mm/s where basically non of the paths were cut correctly. Only a few dots, likey beginnings/ends of paths…

My 2.5W laser diode is powered from the PCB that came with it - a bunch of ICs, DC-DC step down convertes, and an op-amp. The "datasheet" says 0-5V TTL, which I connected to HEATER_3.
The power input for the laser PCB is a 12V DC-DC converter that is fed by my 24V PSU.
The laser fan (12V presumably) is connected to the laser PCB, and is always on. So there is always a small load on the 24V->12V converter.

I will do more test patterns, and maybe add a big electrolytic cap on the buck converter.

edit:
I used http://jherrm.com/gcode-viewer/ to simulate my gcode - and I think the incomplete paths are from the beginning, i.e. The laser is turned on too late (or reaches full power too late). This results in a few moves already being completed before actually cutting happens.

@Barracuda72:

yeah..that was me, asking him when he will do the review 😉 couldnt resist to ask for a non-prusa mk3 review 😉

Haha that made me giggle 🙂

I couldn't help but comment on his video either lol

Hmm my flying extruder mount is definitely putting some sideways forces to the arms so i guess that the PLA got slightly soft and that made it to warp. Gotta revise the mount again and swap the arms ?

Hi,
unfortunately 15W isn't real power it has average 8W.
But it can mark black anodized aluminum plate with one pass (F500). And It can cut 3mm wood with 3-4 pass.
Now i haven't any video and any picture, because my printer has a changeable head and now it is plugged in over 4nozzle filament head.

I wouldn't have thought that any of those are huge problems that can't be dealt with. I'm just thinking that a UPS is essentially a battery running an inverter to give mains voltage. This mains voltage is then stepped down to DC voltage by the printer PSU. From what little I understand, inverters aren't the most efficient devices and there would also be some losses through the PSU itself. So it seems to me to be reasonable to cut out the step up to mains voltage\step do back down to DC aspect and just supply DC directly.

Someone cleverer than I could probably build a circuit that would trickle charge the battery from the printer PSU maybe, then when mains is lost, it switches over to the battery? A bit like a UPS but without the inverter. Just musing…......

Not that it would work for me as my bed is 240V AC.

EDIT. A quick google search shows that one can already buy power supplies with integral DC UPS - might be the way to go for printers with non AC bed heaters?

In fact thinking about it, my 10mm thick insulated aluminium build plate takes forever to cool down so if the power failed once it was up to temperature, I could probably still print for quite a while by just maintaining the DC side of things before the part falls off the bed. Might look into this a bit further.............

EDIT2. How about something like this? https://www.simplypowersupply.com/DC-UPS/AD-155C-Meanwell-24V-155W-DC-UPS.aspx

I use Simplify3D as my primary slicer for my two printers. I have a T3P3 Kossel Mini Delta printer with DuetWifi. I have my start script heat part way, do a G32 auto-calibration, then heat the rest of the way to the requested settings.

[[language]] ; Multi-temp stuff - 10 Feb 2018 ; Raise bed temp to profile requested bed temp M140 S[bed1_temperature] ; Raise bed temp to profile requested bed temp M104 S75 T0 ; Raise hot-end temp to 75C for G32 auto-calibration M190 S[bed1_temperature] ; Wait for bed temp to rise M109 S75 T0 ; Wait for hot-end temp to rise to 75C G28 ; home all axes G32 ; Autocalibrate M104 S[extruder0_temperature] T0 ; Raise hot-end temp to profile requested hot-end layer 1 temp M109 S[extruder0_temperature] T0 ; Wait for hot-end temp to rise to profile requested hot-end layer 1 temp G1 X0 Y0 Z10 F8000 ; centre nozzle 10mm above bed M572 D0 S0.25 ; Pressure Advance - 25 Feb 2018 ; end of my start code

There is a comparison of the achievable step rates and travel speeds supported by various electronics/firmware combinations at http://reprap.org/wiki/Step_rates.

It would be nice if the slicer could generate a command at the start of the gcode that specifies the X and Y limits of the print using M557 or similar. Maybe you should ask @burtoogle nicely to put that facility in Cura?

If you print outside the probed grid then the firmware computes the height error by extrapolating the average tilt in the X and Y directions.

thank you

After an axis has been homed, the movement along that axis is constrained to the limits you specified using M208. The latest RC firmware also forbids most types of move before the axis concerned has been homed.

However, forbidding movement in a region whose XY limits depend on Z is a highly specialised requirement, so I am unlikely to implement it. But RRF is open source, so by all means implement it yourself!

Alternatively, why not either modify your printer to avoid having that forbidden zone, or move the X endstop to the high end of the axis? You may even be able to use stall detection to home X to the high end, then home Y and Z, then home X to your low end switch.

I'm sorry, I don't understand your post. Please explain what you mean by "the head gets 3-4 mm high from the trays and I set it to be 1 mm between the card and the nozzle height".

dc42,
Thanks for pointing out that guide to me. It has helped me a ton.

/quadcells

Addendum on the right-clicking.

On my Macbook Pro 15 inch right clicking means holding the control key and clicking with the mouse.

Normal behaviour is that, after releasing the mouse button the popup menu remains and you can then stroke the trackpad to select the desired item.

In the 1.20 Webcontrol you have to HOLD the trackpad down whilst simultaneously stroking it to find the desired item. This is quite difficult to do, particularly when you have the habit of working otherwise.

With hindsight might well have tried right clicking and had no luck. Because generally click-release quickly would have seen nothing.

Ah, that all makes sense now. Many thanks to you both. I'll get editing!

In principle that should be OK, but I have a distrust of mechanical relays.

Did the configuration according your proposal and can verify it's working.

For reference here are the relevant parts.

config.g

[[language]] M581 Y1:0 S1 T0 C0 ; Emergency Stop everytime E1 (Y-Min) is triggered

homey.g

[[language]] M581 Y1:0 S-1 T0 C0; Disable Y-Min Emergency Stop G91 ; relative positioning G1 Z5 F6000 ; lift Z relative to current position G1 S1 Y-293 F1800 ; move quickly to Y axis endstop and stop there (first pass) G1 Y5 F6000 ; go back a few mm G1 S1 Y-293 F360 ; move slowly to Y axis endstop once more (second pass) G1 Y1 F6000 ; move out of endstop by 1mm G92 Y0 ; Set Y to 0 G1 Z-5 F6000 ; lower Z again G90 ; absolute positioning M581 Y1:0 S1 T0 C0; Enable Y-Min Emergency Stop

@Barracuda72:

ok..made a calibration cube..
1. with Cura 15.04
https://drive.google.com/file/d/15f5AtY0VROXYdu-Rqe2Fgv7t0LyyHXp-/view?usp=sharing

2. with Simplify3D
https://drive.google.com/file/d/17FLBhOeISPs6M6-l8X4HPyd2fQa3IvDW/view?usp=sharing

most settings are similar except in the S3D file the printer do that little wipe line before the print. Even tried to erase the 2nd G92E0

With the Cura file the layer informations are ok..he count each layer.

With the S3D file its only 1 long layer in the DWC…first layer 1. sec ( thats the prime/wipe line in my starting code)..2nd layer...endless

DWC after the S3D print: "Layer: 2 of 83, Filament Usage: 1598.2mm of 1601.2mm (3.0mm remaining)"

strange

hmm I should start doing LEGO bricks instead of Calibration Cube..so they are at least useful 😉

The problem is this line:

G1 X-44 Y-75 Z0.2 E0.5 F7000 ; Drop to bed

The firmware treats it as a printing move because it contains both extrusion and XY movement. Z is very high at that point, which throws off the layer height computation. The workaround is to do the extrusion in a separate move.

The reason that it worked in 1.20 is that in 1.21 the layer height code was changed to allow for slicers that use variable layer height.

Hi ,

hat seems more plausible, the OP did not specify if actual the print was OK

Yes it printed more or less correct a little Z axis problems with a layer slip , but not that bad for a set up print.

I checked cura, Printer Machine > extruder1 , 1.75mm filament which is correct and a .4mm nozzle.

he Duet gets the filament usage from a comment that Cura wrote near the end of the GCode file.

o.k looked at the gcode in a text editor and what it says at the bottom of the screen is different to what`s imbedded !!!!

;FLAVOR:RepRap
;TIME:40953
;Filament used: 32.0279m
;Layer height: 0.2
;Generated with Cura_SteamEngine 3.2.1
T0
M190 S60
M104 S210
M109 S210
M82 ;absolute extrusion mode
G28 ;Home
G1 Z15.0 F6000 ;Move the platform down 15mm
;Prime the extruder
G92 E0
G1 F200 E3
G92 E0

The problem was I used an insufficent value in the configurator originally for the Maximum carriage travel value, which in turn got translated to an insufficent value for the first G1 S1 command in the homedalta.g

Thank you for the help!

Btw:
The RRF configurator's default value is 250 for "Homed Height", and 260 for "Maximum carriage travel"
The tooltip is "Maximum travel in Z direction" which is misleading (Or at least it was for me).

Wouldn't a default value around 450 (homed height + the pulley movement to acheive max X or max Y position), and a tooltip "Maximum travel of a pulley" be more appropriate?

oooh.. of course. I see the logic now.

Thank you! Will redo this tonight.