Inconsistant travel in the x and y axis of a Kossel

[tkcad]

HI All,

I am new to 3D Printing and took on the challenge of building my own Kossel Delta the size I wanted. Build volume of 450mm x 800 mm. The machine is solid with side to ensure rigidity, has ball bearing carraiges and guides. It has the power to lift the 10 pound build plate (that was and accidental).
During the raft construction on the very first layer I could see and hear movement in the nozzle that left a little blop of plastic in the long straight runs. This continues through the entire build. My layer height is .2mm speed of printing was set to 1500 mm/s but the raft was so slow I cranked it up to 200% until it was finished than reduced it to 100% for the rest of the print. The quality of the print is quite high but I still see lots of tiny zits on the sides. The top surface very good with only a few blops. I don't know the quality of the floor yet as I have to remove the raft with my milling machine as it is too solidly attached.

Any ideas on how to fix the blop problem? I am a little stumped as it happens even at very slow feedrates. I considered baudrate an issue as I was printing with USB from Simplify3D but it is at 250000. Maybe 1/32 steps is to fine for the Arduino to handle. It may be related to the inability to move faster than 1500 mm/s with out the arduino freezing and rebooting itself in the middle of the pass.

Any tips on making an easier to remove raft that prints a lot faster.

[CompoundCarl]

For the blobs, I would suggest starting here: https://www.simplify3d.com/support/prin ... s-and-zits

And honestly, for the raft questions, I would strongly suggest NOT using a raft. There's lots of better options like brims and I for one was very happy once I finally gave up on rafts and started using better options.

[tkcad]

I wonder if my extruder multiplier is to high? because my layers are straight and the zit is not occurring on the ends or even close to a direction change and is relatively consistent being about 15mm apart. Perhaps the tip is building up pressure than pushing the nozzle enough to relieve the excess pressure leaving a zit.

I went through the guide prior to posting.
Thanks,


I sped up my print speed and all inconsistency disappears and it now makes it across the entire build plate with out reboot half way. But I have to go above 100 mm/min which results in lower quality of print. So at slow slow speeds it works with imperfect travel, at reasonable speed an OK print with inconsistency, and at high speed nice movement and smooth but reduce quality.

Has anyone else had issues like this?