any body had/having issues with ghosting/sharp corners

for a little while now ive been having issues with ghosting and with sharp corners, in many cases getting horrible ghosting or where it seems to overshoot and return to the proper position.

this has been a long running issue and after finally whittling down the long list this is a last and wondered if anyone has had anthing similar and has any suggestions.

my acceleration is set to 2000.
ive tried changing the speeds to see if the speed is just causing issues, but the issues barely change.

its actually fascinating to see as on sharp corners it gives a perfect example of a second order oscillatory response, i just carnt think of anyway to increase the dampening in the system to stamp it out.

The only things I can think of that would affect it are speed, acceleration, belt tension and motor current. If it has changed over time I would suspect belt tension.

To some extent it is an inevitable property of the mechanical system. Whether it is noticeable on prints depends on the plastic. More viscous plastic like ABS does not respond to high frequency vibrations. Shiny plastics show defects a lot more than mat ones. Lower temperatures make the plastic more viscous and less shiny.

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[www.hydraraptor.blogspot.com]

just as a guide line how much tension would you recommend, in your guide it says to make a low note, which they currently are roughly, but just to fine tune them if need be?


your prints look almost perfect its just frustrating haha.

I don't have anything more specific and I don't know exactly what effect more or less tension has on ringing. Have you got a picture? Is it any worse than this [forums.reprap.org] ?

I can only see a very minor effect with shiny PLA, nothing with the white ABS I use to print the kits although most of the parts in the kits have rounded corners to make them easier to print. I don't see anything I would describe as overshoot although ringing is obviously 50% overshoot, 50% undershoot.

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[www.hydraraptor.blogspot.com]

its hard to get the issue on camera with this blue abs, but if you look at the corners, theres a ridge on the forward path of the ridges, while on the image it doesnt seem like much in reality it can cause some real issues when trying to print.

The odd thing is the waves in the curved recess are aligned vertically but the last edge which would trigger ringing isn't. I.e. I would expect ringing to be aligned with the curved edge.

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[www.hydraraptor.blogspot.com]

I had and have this problem too, I call it "overshooting edges". I seems to be solved or getting better, when lowering the print speed. It might have something to do with the inertia of the extruded material.