0.9.2 wobbling issue

There is some weird wobbling like behaviour that 0.9.2 causes. In the attachement you can see two gears, printed right after each other on the same printer, the good one was sliced using 0.7.2b the bad one with 0.9.2.

It is not a Z-wobbling issue from the threaded rod, as it is only present on one of the gears, and the period is about 7-8 layers with 0.25 layer height, that is 1.75-2 mm. (I'm using M5 z-rods, they have a 0.8mm period)

What is causing this? What have changed since 0.7.2b? I'm using the same settings for both versions.

I'll chime in to say I think I may be seeing this behaviour too. I noticed that my prints over the last couple of days have had considerable waves in the Z axis whereas previously I had virtually eliminated Z wobble. I put it down to something going wrong mechanically in my machine, but it's interesting to see this post because I actually started using the dev code to produce gcode just a couple of days ago.

I'll retry the prints with an older version to make a comparison tomorrow.

Is anyone else seeing this? It would be quite strange if it's a bug in Slic3r!

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garyhodgson.com/reprap | reprap.development-tracker.info | thingtracker.net

You know what, I am seeing the same thing when I decided to try 0.9.2. I get this wavy perimeter and I thought it was my z axis acting up since there was a pattern going on. Every couple of layers, it gets wider and then after a few more layers after that, it gets smaller. I switched back to 0.9.1 using the same settings created in 0.9.2 and get the same results. I am going back to 0.7.2b to see if this goes away and I hope it does because this was driving me crazy for the past few days.

I saw this sort of thing (I'm assuming you mean waves in the Z direction) and when I saw this thread was thinking it might be the same thing.

However I needed to change colours for a print job (at the moment I only print in PLA), and the problem has now gone away!

I have a suspicion that the roll that was on the printer previously (that I was getting the wavy issue with) has absorbed moisture over time (I've had it for more than 12 months), and this may have been causing my issue.

Since I have a bit of PLA left on that roll, I'm going to try baking it and seeing if the problem comes back or disappears the nest time I use it.

Dunno if it's related to your issue, but no real harm in trying!

I've definilty noticed some surface weirdness on our machine, but it's hard to say how much of it is due to some issues with the mechanical system.

However, what I can confidently report on is very inconsistent results slicing a simple shot-glass style object with slic3r v082, 083, 091, & 092. Print quality is *significantly* and clearly better using version 082, even with the settings kept as constant between versions as possible.

This is unfortunate, 'cause the more granular control of the later versions is really nice -- I had been playing around with faster settings for the infill and inner perimeters, steping down to low speed only for the outter perimeter, but the speed bump isn't worth the PITA of getting gcode that seems to be producing worse prints.

L