Unresolved Calibration question

I found cylinders I print do not seem perfectly round. So, I printed the calibration cube.

It is a bit difficult to measure due to the "over run" at the corners.

I suspect EEPROM adjustment to do with acceleration and/or direction changes could help, but rather than hack away, I figured to post these pictures to get some feedback/advice on how to correct the issue.

Gonna wait for some response before I knock down the corners and attempt to measure again.

 

Most of the measurable overshoot seems to be in the Y axis. Could this be a belt tightness issue?

 

Which way? I thought it was tight enough by "twanging" it.

 

This is where I am now. Even less?

#define DEFAULT_MAX_FEEDRATE {500, 500, 5, 25} // (mm/sec)
#define DEFAULT_MAX_ACCELERATION {300,300,100,500} // X, Y, Z, E maximum start speed for accelerated moves. /robo R1 jfa 11/18/2019
#define DEFAULT_ACCELERATION 300 // X, Y, Z and E max acceleration in mm/s^2 for printing moves /robo
#define DEFAULT_RETRACT_ACCELERATION 1000 // X, Y, Z and E max acceleration in mm/s^2 for retracts

// The speed change that does not require acceleration (i.e. the software might assume it can be done instantaneously)
#define DEFAULT_XYJERK 5.0 // (mm/sec)
//#define DEFAULT_XYJERK 17.0 // (mm/sec)
#define DEFAULT_ZJERK 0.4 // (mm/sec)
#define DEFAULT_EJERK 5.0 // (mm/sec)

 

You know, I did, sorta recently, change the linear bearings and maybe the rods. I'll have to check any records I may have. Was about the time I did the lead screw conversion.

FWIW, I did knock down the corners and find x,y,z within .003 of each other. Is that as good as it gets?

 

Did you really mean MICRONS?

 

So, I am not that far off. Still 0.4. even with the new hot end. I just ordered a hardened 0.4 to use with the carbon fiber filament.

 

GAH! I should start a new thread but suddenly I cannot get even the skirts to stick. I did reinstall MC 1.5 over the existing, thinking to restore the sync to print feature in layer view. But a quick glance looks like all the parameters are as before.

This is what I get:


the Z offset is .5mm Could that be it?

 

Expect it to be delivered today and may get to test it. Titanium. Well, since the Soviets stopped trying to build Submarines out of it, maybe the supply has loosened up . . .

Anyway, today I made a test print of a tool I hope to use, (CAD files courtesy of some fantastic folks at FreeCAD). I was ecstatic over how well it turned out and that it did not break when given a flex test, but then notice how it was "shrunk" in Z axis at the base. I may still be able to use this print, but wonder why that happened. As the print time was estimated at 9+ hours I did not print a raft as it seemed unnecessary. Wrong? I did not notice which way it printed as to x-y orientation.

I am a bit disappointed at the "ridges" that seem more pronounced than I've come to expect.

 

I had manually leveled the bed and it seemed improved, but upon starting print for this test tool, there was one strand that thinned/did not adhere, similar to what was shown earlier.

I let it run and is seemed to clear up, so I let it print completely, checking periodically to see how it was going. All looked fine, until I examined the piece much later, after a test fit. Now it appears to me that the first few layers, in that area of mal adhesion seem to have "shrunk" in the Z plan (height) which makes me wonder if it is all related. That area is all "grid fill" which I had set to 20% as a time and filament saving effort. No idea if that worsened the problem or not.

 

Not sure I followed. The difference in this case is around 0.1 inches. That is far from OK in my estimation. I'm not at all sure why this happened, all I can say is it looks to my eye that all the shrinkage happened in the layers at the bottom 1/4 inch or less. No clue if that was due to a filament issue or what.

I will attempt a nozzle change since the hardened steel on arrived and run another test tomorrow or so.