The effect of multiplier and z height on first layer ripples and waves
Hi all,
I recently added a noctua fan mod to my prusa i3 mk2S and recalibrated everything after the installation. Unfortunately even after calibrating first layer height to what I thought was the right height, all my prints were failing. I had first layer rippling and waves which are usually indicative of nozzle height too close to the bed, but if I raised it up even a little bit my calibration prints wouldn't stick (Prusa PLA, stock slic3r settings in slic3r PE).
I read in another forum that lowering the extrusion multiplier could help, so i documented my progress of lowering the multiplier and then incrementally raising z nozzle height by increments of 5 microns, shown here:
As you can see, the first layer got incrementally better every time I lowered the multiplier and then even better as I raised Z height. I ended with the multiplier at 94% and raising Z height by 30 microns:
it's still not perfect by any means, but much much better and I'll probably tinker more as time goes on.
I'm not suggesting everyone do this by any means, I'm just showing my documentation for people who also may be having problems with waves and ripples on their first layer.
Re: The effect of multiplier and z height on first layer ripples and waves
I too run with a flow of around 90-94%. Usually by the third layer things have smoothed themselves out, though I'm wondering if the trend in PLA filaments is to require lower nozzle temperatures.
Re: The effect of multiplier and z height on first layer ripples and waves
Yes, I may go down even further, to 93% or 92%. Cooling my be an issue too because I wasn't having these problems at all with the stock fan, so I'll tinker with nozzle temp in the future as well. Not too much though- I have a hardened steel nozzle and have noticed that nozzle temps need to be a little higher with that material nozzle.
Re: The effect of multiplier and z height on first layer ripples and waves
Based on the pattern of the ripples, it looks like the left front corner of your heat bed is higher than the right. Have you done any fine tuning of the mesh bed leveling?
Re: The effect of multiplier and z height on first layer ripples and waves
I have not! Its on my to-do list, but I pushed it back because I thought I'd get the new bed from my mk2 -> mk2.5 upgrade by now. Figured I'd wait until then to make fine adjustments.
I may do it anyways though, since I'm not sure when my upgrade kit will be shipped out! That rippling has really died down, and its almost unnoticeable when I print in PETG.