I'm still having z height issues on my dual hotend delta.
It's not that it doesn't work or print but it's extremely time consuming to set it up, I feel like my config could be better and/or I'm running in to some issues where I don't really understand why the settings I'm changing don't seem to affect the print height at all, at times, and then they do, other times.
Is anyone offering paid support ?
The printer is actually very simple, maybe I should try another firmware ?
duet looks really nice and when it prints it prints well, but I don't think I've done many print where I'm not compensating with babystepping, which doesn't always seem to work very well either.
No paid support unless someone offers themselves up. But we do offer free support.
If you'd like some help, please post some details about the printer and your setup. Also provide your config.g, config-override.g, homedelta.g, bed.g, and the results of M122 and M98 P"config.g".
Give us the specific problems and how to reproduce them. Photos or videos can help a lot.
It couldn't hurt to ask I guess.
I don't really have specific issues I think.
I have observed that I need to double babystepping when starting my second print, I don't home between prints, I would like to know if this is a known bug/issue or an issue on my end.
I would prefer to not use babystepping at all, and set the head offset directly.
However, setting the Z offset of the head/tool does not actually alters the height of the head directly ? This is still the case ?
Both these issues seem to have the end result that setting the correct Z height for a dual head printer is a lot of work, this means I end up spending more time tuning the printer than printing.
I would like to know if there is a better way, it's not so much that I can't get it to work , it's more that these settings will only be good until the next clog and that clog could cost me hours in setting the correct height again.
Some (all) of this is off course user error.
So, is it possible to just avoid babystepping and have something similar that is saved between prints and reboots and allows me to set the Z height of head 1 & head 2 using an up or down button and/or with the offset command so the head moves to the new position and also remembers that this z-offset needs to be applied from now on until I change it again.
I have included an image of the printer, it's really a very simple kossel based design with dual extrusion.
both heads are on a rotating part bringing either head 1 or head 2 down.
probing can be done by putting an M6 bolt between the mechanism so both heads are placed "symetrical", the endstop is a simple microswitch on the bottom of the part cooler/blower.
Switching itself is a simple on/off that switched a valve fills one of the both ends of the pneumatic cylinder.
It works well fairly well actually but still needs some work for it to work well in +50 degrees celcius.
@brampie Sounds like you'd be served by using Z-offsets stored in G10 (until RRF3.3 changes that, if i read the upgrade notes correctly) - I use different Z-offsets on my toolchanger and get very repeatable toolchanges and first layers using this implementation.
thx for your info
No I have:
G31 P500 X-12.5 Y-17.5 Z-2.07
to set the probe trigger height
G10 P0 X-4.32 Y-4.5 Z0
G10 P1 X4.32 Y4.5 Z-0.2
A command like G10 P0 X-4.32 Y-4.5 Z10 does not really have the effect of the head going up.
You have G10 Z commands where the head does move while you send the command ? I was under the impression this was not possible.
I have been able to get good repeatable results, but setting the height for 2 heads this way takes too long when dealing with filament that clogs easily
I'm really looking for a way like the G10 command that actually moves the head up and down so I all have to do is check with the G10 command what the correct height is and then copy past that into the config.
It would also make adjusting while printing and applying that adjustment later easier.
Not, adjusting with babystepping, applying that different to the config file, rebooting, checking, make another small adjustment.
This would save me so much time.
Updating the G10 coordinate should update where the machine shows its at - So if you have T0 selected, and you level your nozzle and it shows your location as Z0 - you then change your offset by G10 Z10 - This should change the displayed coordinate by 10. you can then check your new coordinate by typing in a move command for Z to bring it to wherever the new coordinates are.
Basically, if i load up a tool, and then go to the homing spot, and try to paper-level my bed. I find that the nozzle scrapes at reported coordinate Z=.5mm - i then issue a G10 command which adds -.5mm to my tool offset. DWC should then report Z=0 - the machine didn't move, but where it thinks it is did. That should be your instant feedback - find the real-life "zero" location, and then adjust your tool offsets (or maybe your probe offset) to where that real zero is.
As a nomenclature thing - I greatly prefer having the probe as the "0" Z location and having both tools be located off of that - if you're switching around your tools (but not dissassembling/messing with your probe) it makes the most sense to have the probe as your stable "0" and have both tools have offsets from it.
This would mean
G31 P500 X-12.5 Y-17.5 Z0
and for head 1:
G10 P0 X-4.32 Y-4.5 Z-2.45
This does have the downside of being able to crash the head into the bed as I've just found out (should have used an old bed to try this), but it does make more sense.
Does this solve the issue of adjusting while printing, should I be able to use this command to lower the nozzle while printing the first layer and then pasting to commands in the config file.
Sorry about crashing into the bed! - I always take that as a risk when printing. Not sure how to get around it as I use mesh leveling which has its unique positional offsets.
As for saving into configs, yes, you can adjust the G10 values to whatever they need to be, and then save them into the config.g for next time - nothing prevents permanent updates. For my particular toolchanger, my Config.g actually calls a macro file that has all of my tool definitions - when i want to update/revert the values, all i have to do is run the tool_conf.g macro file and poof, the values are re-done. You could create this macro and keep your offsets in there, and then easily save and update your values.
My bad, I was using the smartphone and pressed the y-50 button by accident, a nice scratch info the new aluminium plate.
Shouldn't duet stop at the height of the offset when the head is active actually, or at least ask for confirmation before going to 0 ?
I guess not using the buttons X,Y,Z on the web interface solves that, maybe a head1-z=0 macro button instead
Yes, I get that, but if I print the first layer with head1, and I see it needs to be lower, and I change the value, will duet, while printing, see that Z is no longer correct and adust while printing in this case.
I thought there was an issue (read it on the forum somewhere that the nozzle only moves when the next Gcode run that includes a Z height) that prevented this.
Or can you confirm that this does work, using these command while printing the head/nozzle does lower "immediately" ?
I managed a couple of prints without further adjustments, after 3 prints I needed to adjust the head -0.9mm with babystepping, homing again did not help here.
Resetting did help somewhat, but I'm now on +0.2mm with babystepping.
I did M500 before rebooting hoping that the config would be saved, I did not do delta calibration after reboot.
The documentation does suggest this but:
-When printing on some surfaces that are less flat I find that delta calibration can cause skewed prints, maybe because it's difficult to tell the difference between a bed that is mounted at an angle and a tufnol plate that is somewhat warped.
I do delta calibration on a clean flat aluminium plate, then if I need to print on something other than that plate, I switch plates and do mesh compensation.
-With my printer delta calibration requires the head to be in the halfway position, this requires manual intervention
You think this causes me to have these issues ?
You think this causes me to have these issues ?
All I know about deltas is from here: