Strange Z error
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@fcwilt well, it seems to be a standard feature in slicers. At least Prusaslicer and Cura got it and in Prusaslicer most presets seem to make use of it. Different layer height, extrusion width, nozzle temperature and bed temperature in order to enhance first layer adhesion appears to be quite common.
Not sure, but I was guessing that for example with PLA, because 70 bed temp for first layer is sometimes usefull, going back down to 60 might be good in order to reduce the likelhood of warping, as it causes the bottom to be less soft.
I thought PLA would rarely warp, but found that especially with very fine layers and 0.25mm nozzle, PLA starts to be quite tricky on some prints. I didnt quite come to a final conclusion yet, but doesnt a different first layer temp have quite an impact in certain situations?
So my idea was to add a command to the filament specific config.g, that overwrites an "other layer temperature" macro, depending on the M701 material in use. That macro then should be possible to be called with custom gcode in the slicer. Maybe on layer change with an if statement, so it does not activate on first layer. Something like that.
@phaedrux in your z probe offset macro, can any problem appear if i return to normal motor currents by simply setting it back to 100%? Like on a power loss or anything? Or would that be a perfectly save approach?
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@suntoxx said in Strange Z error:
it seems to be a standard feature in slicers. At least Prusaslicer and Cura got it and in Prusaslicer most presets seem to make use of it. Different layer height, extrusion width, nozzle temperature and bed temperature in order to enhance first layer adhesion appears to be quite common.
True, slicers have all sorts of settings designed to deal with first layer adhesion. And the number of possible combinations of those settings is daunting.
Not sure, but I was guessing that for example with PLA, because 70 bed temp for first layer is sometimes usefull, going back down to 60 might be good in order to reduce the likelhood of warping, as it causes the bottom to be less soft.
My beds are rather massive and any temp changes I might try to make are going to be rather slow to take effect.
I thought PLA would rarely warp, but found that especially with very fine layers and 0.25mm nozzle, PLA starts to be quite tricky on some prints. I didnt quite come to a final conclusion yet, but doesnt a different first layer temp have quite an impact in certain situations?
I honestly don't know. The biggest factor I found for first layer adhesion has been speed.
So my idea was to add a command to the filament specific config.g, that overwrites an "other layer temperature" macro, depending on the M701 material in use. That macro then should be possible to be called with custom gcode in the slicer. Maybe on layer change with an if statement, so it does not activate on first layer. Something like that.
If I was going to implement a temperature change feature it would involve using the slicer feature that allows invoking custom code on each layer change. It would be easy to have the filament specific config.g file set some global variables holding different temperatures and layer counts. Then the layer change custom code would use those values to determine what temperature to be using for the current layer.
I am going to try that just to see what sort of effect changing bed temp might have.
Frederick
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@fcwilt said in Strange Z error:
I honestly don't know. The biggest factor I found for first layer adhesion has been speed.
In which way? I experienced, that a keychain i did in various sizes and with different layer thickness and nozzles, started to warp very easily, when using the .25 nozzle and a certain size and thickness. The smallest version printed fine, the 20% bigger version, started to warp, despite strong layer adhesion. Not sure if it is the longer print time that caused it, or maybe the number of layers and the way they cool down being that thin. Maybe they are just super prone to moving air, when the layers are that thin (was .12mm layers).
What speed to you use? By now I always left it at the default 20mms. I only once had layer adhesion problems that were not z offset related, and solved them by increasing bed and nozzle temp beyond the temperatures recommended by the manufacturer. (was Fillamentum Vertigo Space and used 235° 70°C, then even fine outlines would stick).
If I was going to implement a temperature change feature it would involve using the slicer feature that allows invoking custom code on each layer change. It would be easy to have the filament specific config.g file set some global variables holding different temperatures and layer counts. Then the layer change custom code would use those values to determine what temperature to be using for the current layer.
I am going to try that just to see what sort of effect changing bed temp might have.
Setting variables would be probably much cleaner. I was thinking of using the echo command to create for example an "Additional-Filamentsettings.g" makro and add a sort of "if layer>1 then execute Additional-Filamentsettings.g" in the layer change custom code.
So I would just have to copy and paste that echo section into each filament config.g and simply set the desired values there and every time I use DWC or M701 to change the type of filament, the echo command would overwrite the Additional-Filamentsettings.g with the current values.
