[How to get rid these artifacts ? (picture included)]

Well, so "printing direction" means... "Z direction".

I'm not sure why did you make this choice of positioning the part (looks like part of an enclosure with ventilation holes, but is just an impression). The point here is that the piece seems to be longer in the "print direction", which makes it somehow fragile.

This being said, the area between the holes is perhaps 5 mm or so. 50 mm/s is too much for such short perimeters. At the corners, the nozzle will drag the extrusion a bit in the new direction so that it will not be laid straight. Additional to the advice in the post above, just try to increase fan speed.

Yes, Z-direction.

It's indeed an enclosure with ventilation holes. It's printed this way because any other direction would have more overhangs. The area between the holes is about 7mm.

I now redesigned the ventilation holes to not have these small islands. But it's good to know that slower printing and increased fan speed might help.

thanks!

 

[How to get rid these artifacts ? (picture included)]

In specific areas i'm getting artifacts. Any tips to improve the quality in these areas ?

Printed on an UM2, PLA(210c), 0.25 layer thickness, 50mm/s speed.