owh movable bed design. Yeah alot higher mass and ur X axis is a bowden setup. It should be fine.

corexy box project, sudah lama stop sekarang masa untuk siapkan semua

[attachmentid=6230474]
[attachmentid=6230487]

I have a prusa too. I dont like this design tho. Its too wobbly. I cant go above 80mm/s without it shaking too much

aluminum. But without rear braces. like the original prusa i3.

much stronger but it lacks rigidity and the resonance frequency is quite low.

can upload a higher res image? cant see the problem. so pixelated

vertical banding(ringing) or the horizontal banding one?

last fix u can do to reduce the vertical banding is to remove the spring beneath the heated bed. replace it with nuts and washers so that its stiff. It improved my prints dramatically. CAUTION: head crash can be devastating!

As for the horizontal banding. Err. I dont know how else to improve print quality. one test you can do is to increase/decrease your step/mm for the z-axis slightly. 1 - 2 % and see if the banding moves or reduce. If it does you can confirm that there is inaccuracy in the Z-axis height. Caused by: Backlash (unlikely), vibration and wobble (more likely) or simply wrong step/mm for the z axis.

If changing step/mm doesnt affect the banding at all. Its safe to conclude that the problem DOES NOT lie in the Z-axis and may come from elsewhere. Inconsistent pressure in the hotend, slicer error or too high of a printing speed.

isnt 5086 too low? im assuming u're using a 8mm leadscrew. That and the DRV8825 driver can do 1/32 microstepping. Should give you 5120 step/mm.

unlike the other belt driven axis, leadscrew arent suppose to be affected by hysteresis. so using the mathematical value of 5120 should be prefered. Then if the z-axis fail to move by the desired amount, you should troubleshoot the cause for it. Mainly backlash is the cause.

What is your Z resolution without microstep?

It looks like your layer height is not in multiples of your Z resolution without microstep. Do you know your lead screw specs?
Don't rely on microsteps for your resolution, the stepper will likely skip because the torque in microstep mode is way lower than the normal mode. At 1/16 microstep the torque is only 10% of your motors rated torque.

http://www.micromo.com/microstepping-myths-and-realities

The consequence is that if the load torque plus the motor’s friction and detent torque is greater than the incremental torque of a microstep successive microsteps will have to be realized until the accumulated torque exceeds the load torque plus the motor’s friction and detent torque.

Simply stated, taking a microstep does not mean the motor will actually move!  And if reversing direction is desired a whopping number of microsteps may be needed before movement occurs.  That’s because the motor shaft torque must be decremented from whatever positive value it has to a negative value that will have sufficient torque to cause motion in the negative direction.

Your steps/mm seems off.

if your using 2mm lead, 1.8 degree stepper

it should be

1/16 ustep, 1600s/mm
1/32 ustep, 3200s/mm
1/8  ustep,  800s/mm
even if you are using 1mm lead , the 5086 steps/mm seems a little bit off.

can you print a shape that has multiple height step? Like a staircase. Check the height for each level.

http://3.bp.blogspot.com/-wAVXLAcqFQA/UaGH...00/DSCN2810.JPG

We're looking for systematic error to fix. random error caused by poor tolerance is out of our hand.

That's is a lot of nuts to change

If not mistaken, I bought mine for about RM 25 per 30cm leads so to me it's quite reasonably priced. I got them through another person who ordered from china.
Looks like the Z-axis bracket is quite thin. Have you observe any flexing on the bracket each time there is a change in height?

hmm. your printer is printing correctly for 4/5 heights. 2 on the lowest one and 2 of the highest ones. nothing much wrong with z-axis. 

altan is referring to your motor mounts for the z-axis.

the anti backlash system is similar to mine 

Sorry for the late reply, it's the top part that the anti backlash nuts are pressed against. Also, check the motor mounts for flexing too...

where do you get the springs? i've been trying to find spring shops