wavy edges

Hey all,

Trying to tune my printer and getting very close, I'm seeing a strange phenomenon though.

This is a picture of the side of a frog, as you can see the edges are waving, there are like 5 layers at the same point on the edge then it juts inward instead of being a smooth taper.

I am printing at 195C black PLA at the default speeds of slic3r.

Any thoughts on how to fix this?

Thanks!

Look for 'wobble' there are many posts with responses to your problem. :-)

i would guess at over constrained z threaded rod, what sort of printer, got a pic?

The threaded rods in the local metal shop were all bent, I managed to find one that was almost perfectly straight and it already took out all the wobble for me.
I also added an aluminum connector with a springy-cut middle part, this stabilizes the rod a bit more and catches some of the wobble.

Those are two things you can try.

Some people say it helps to 'fixate' the threaded rod on the free end, but in my experience, if you don't have a straight rod to begin with, it only makes the wobble worse and puts even more stress on your X-ends.

It looks to me like maybe a polygon model or slicer issue? First, how smooth is the original solid model (stl)? The reason I say that is that going around the frog I see large polygon faces in other directions. The printer can only print as smooth as the model is defined. Are the faces/steps in the Z direction in the model? The perimeters in X and Y control the outlines of each layer which is what you are seeing- like successive layers using the same perimeter for several layers, then the next layer is different (in the X-Y plane).

Make sure you oil the Z rods liberally the problem is often in the anti backlash system ... (nuts and springs ) in the Z axis carriages