At the start of the print it always leaves a hairthin wire from the initial blob at the start point to the start of the print, interfering with the first layer.
Does this mean the printbed is too close to the nozzle ?
What would an ideal distance if I use a feeler measure?
The rough measure of a few layers of paper doesn’t seem to be accurate enough.
I have offen the same issue.
The homing is right-back and the start of the print is at the most left-front point. To me this is asking for this problem.
=> Better should be that the first point to start printing is also the most right-back position. This should be possible to change in the ‘Start G-code’ I think, but I don’t know enough about this.
=> Has any one a suggestion how to change this ‘Start G-code’ so that the first point of printing is the most right-backwards point instead of the most front-left point?
Thanks,
PHD
Unfortunately that is not something that can be resolved by simply changing the start G-Code, because this doesn’t change where the actual printing starts. That is controlled by the G-Code generated by the slicer, so it could only be changed in the slicer settings, but Cura does not offer this option afaik.
G-Code never tells the printer to change the orientation of the object or anything. It’s simply a set of commands in the style of “Go to Xxxx Yxxx and express Exxx amount of filament at the same time”
As a workaround it would be possible to change the point where the nozzle is primed to the front left corner (X200/Y180) in the start G-Code. Or run the printhead around the perimeter before the printing starts. Both of those can be done in the start code.
However it would be far easier to “just” optimize the filament settings in the Cura. This might still leave a fine line, but one that is far to small to have any real signifiance. It could be further reduced by adding a little retraction.
Or print with a raft.
This is not an issue for the nozzle distance to the print bed. Look at it from a different point of view.
The printer is finally comparable to a funnel, where you put a ductile liquid in. The more fluid this liquid is, the more is dripping out of the funnnel.
The viscousity is mainly determined by the heater temperature, so if it drops out too much, the temperature is too high.
On the other side, if the temperature is too low, it becomes impossible to push material through the nozzle.
One aspect of the art of printing is the proper setting of the extrusion temperature. Since there are a lot of different flavours for each material group and a tricky temperature control system for the K8400 hotends you can take all given settinge elsewhere as starting point for your own optimisation.
Before I updated my hotend, I tried to find the best extrusion temperature by the following procedure:
For the proposed temperature range I did the following tests with 10°C temperature variations, starting with the lowest temperature:
Repeat 5 - 10 times:
When you do this with increasing temperatures, you will observe a slightly decrease of filament flow time until you reach a limit, where the flow hardly stops. At this temperature the filament is so liquid, that it will drop out by its own mass.
A good extraction temperature would be 10°C below this critical temperature.
With this starting point you may check the other improvements too.