Solved *Read pg 8 if you use a Geckotek bed!* Changed power supply, now y axis waves

What else is there????

 

New Z lead screws/steppers (they were good and straight).

The RAMPS is new and the Y axis stepper driver is new.

I can see how bent lead screws can cause this, and it would explain the wave action perfectly since the lead screw rotates, but new lead screws/stepper motors ruled all that out. No way the guide rods for Z can cause a back and fourth motion like this. Everything just looks so darn good, it acts like the model calls for it.

 

No, couldn't see how it could be Z not stepping correctly causing Y axis shifting of 2mm.

 

Pics of last test print. Both printed together, the one toward the front almost passable. Also pic of how they were on the print bed.
Running another test print now with 3 towers, middle and two extremes of the Y axis.

 

Before I started this last print, I was checking everything for slop. I found the smallest, and I mean smallest amount of slop in the bearing/rod on the right size of the Z axis. This is probably still less slop than there was with stock rods/bearings (using upgraded 8mm rods and misumi bearings, which are far better of a fit), but the other side is rock solid. Ordered new bearings, but I doubt that little slop could cause all this.

 

Y axis bearings are all good and tight (again Misumi bearings on better rods)

 

I ordered enough bearings for the X axis as well, just cause I was already paying for shipping..

 

If it were me, I'd create a table to review the change management...

Action Better? Worse?
--------- --------- --------

Each of those actions above you'd write in the first column and then put a Y/N/NC (no change) next to each. The initial "replace PSU with new one" is the first 'worse?' in the series and starts this show. You seemed to have a positive response when putting the original PSU back in.

I'm assuming that Y-wave is the only problem. But if you'd added any problems, feel free to add them as a fourth column. Thinking of this as a timeline from top to bottom, it helps to visualize better the change management of everything with everything now in one place and in a timeline.

 

Any chance that it could be the lubrication either in the bearings or the lead screws?

 

All bearings and lead screws are freshly lubricated and moving completely free.

Just checked on the test print, I printed one at the very front of the plate, one in the middle, and one at the back. The one in the very front is acceptable (barely any Y shifting), middle has the Y shifting, and the back one is the most severe.

Now I'm going to do 3 in a row toward the front.

 

Movement is smooth. No side to side slop in the Y axis. My test print last night failed due to the filament binding up and breaking on a new spool, so running it again. Moved all 3 towers right next to each other on the most rear of the Y axis where the last model was the worst. Will see if position on the bed has anything to do with it.

 

One thing that has bothered me since this all started, is the z wobble isn't consistent. Thinking of the pattern as a sound wave, the frequency isn't always the same. Its different with every model attempt. I've measured from peak to peak of between 5.25mm to 2.2mm. The amplitude is always about .65mm

 

Well, the new Misumi bearings arrive tomorrow. Once this test print is done (I'll report the results), I'll take it down again and see if I missed anything.

I think I will stop the print at the peak of issue height and see if something is loose while everything is hot. Haven't done that hot yet.