I have upgraded my K8200 with a E3D v6 head and is overall satisfied with the performance of it.
I have managed to adjust the stepping so that I get very close to 100 mm feed of filament when testing it, but I also suspect that this is what causes the problems that I have with one of my prints:
I have a print that consist of a base plate with 7 identical, slightly conical “chimneys”.
The wall thickness is around 2 mm at the lowest.
When the “chimneys” are being printed, for each layer the extruder will pass most of the “chimneys” with the layer has already been printed.
At some point it becomes very clear that the layers are extending more than the 0.3 mm that is the layer height, and very noticeable “clunks” are heard when the extruder passes the chimney walls.
When the Z-axis lifts for the next layer and passes non-printed chimney walls, no sound is heard, which makes me believe that it in fact is excessive built up of material.
In the end it has resulted in several prints that ended up useless due to - in this case - X-axis shifts, which have been anything from a few mm to several cm.
I then tried to lower the feed rate to about 70-75% of the original feed rate, when starting on the chimneys, and then I was able to get successful prints.
So my questions are:
Should I try to fiddle with the Z-stepping to get rid of the problem, and accept that the feeding will be compromised?
Has anyone seen similar behavior and been able to solve it?
My top layers are generally very coarse with 100% feed rate, but somewhat smoother with lower feed rate. Is this related to above problems?
Hope someone is able to direct me towards a solution to this/these problems.
Thank you for taking time to answer my questions, however that do not seem to be the problem in my case.
I have also upgraded the Z-axís with the K8204 upgrade kit, and it is pretty solid, i.e. no uplift in the Z-axis beam.
I have noticed that especially small details like the rim of the chimneys have very jagged edges, and I think this is what causes the problems.
I am just not sure what to do to get rid of the problem.
I cannot believe that there is not any uplift possibility all. Be aware that a uplift of a few 10th of a mm is enough to cause your problem. Did you measure the potential uplift?
I use metal “binder clips” to hold the glass plate onto the print bed, and if the print head collides with a clip, it will damage the outlet. A damaged nozzle will still print, but the bead of material will not always go where it should. I have seen uneven output from a slightly damaged or clogged nozzle.
Make sure there is no plastic stuck inside the nozzle by running a thin piece of wire through the opening, and inspect the outer surface for any scratches or deformation. It also can help to clean the nozzle with a lint-free cloth before each print job begins.
If you raise the print head a few cm above the bed and extrude material, it should come out in a straight line downward. If the bead curls around, you may have a clogged or damaged nozzle.
Thank you again for taking time to reply to my problems.
I have the following comments and observations:
Uplift can only be caused by pulling the filament off the spool - right?
I have measured the necessary force to pull the filament of the spool to be less than 30 g maximum, and around 20 g in averages. (My K8200 has ball bearing spool holders)
This is far less than the total weight of the Z-axis with extruder.
In my view this rules out the uplift problem.
Unfortunately, I don’t seem to have problems with a damaged print nozzle.
When I extrude filament in the air, it comes out in a straight line as suggested.
Right now I am experiment with lowering the E-steps and increasing the extruder temperature.