I don't know what that is called 

What I understand is that there is a slight under extrusion at certain layers, so they look like there are some minor voids making the layers discolored.

It is probably caused by the retraction parameters if turned on. I notice if the retraction distance or speed is set too high, it will pull in too much air into the melt chamber and mix with the melted plastic. Then when it extrudes, the air bubbles will cause voids in the layers. If the voids are seen on prints without any gap crossing, then its due to the moisture absorbed into the filament (happens for both PLA and ABS). You have to optimize the retraction setting by printing two cubes spaced apart so there is little stringing but doesn't pull too much air into the melt chamber.

Whether its normal or not, if it is little or not noticeable, then its fine but if there are a tons of voids, then that is not normal.

I dont know is mine is same or not, if i look at the printed pieces on the eye level then it perfect layer but when look at certain angle then i can see the layer like in the picture, or maybe i just try to find something wrong with my printer

Its good to find fault with the printer since it helps improve the prints. 

You should do some test to see if it is caused by anything. Probably extruder of hotend related.

Any calibration file do you recommend to see if i really got the problem or im just try to find something to adjust with my printer

Is the line show with the blue arrow normal cause my printer also sometimes got lines like that, and do you know what it called? and can we fix it?

Its called banding. A z-axis artifact. I've encountered it alot. In my case it was Z axis wobble from lead screw not being perfectly aligned to its centre of rotation. Try printing a tall cube and see if it bands at regular intervals. If it does its caused by Z wobble.

Or it could be caused by your slicer rounding over the microstepping intervals like here http://www.soliforum.com/topic/1465/taxono...axis-artifacts/

Guys! I need help. My extruder arent able to extrude a constant flow of PLA. what seems to the problem here? thanks in advance.

Guys! I need help. My extruder arent able to extrude a constant flow of PLA. what seems to the problem here? thanks in advance.

I think i manage to fix 70% my banding issue left cube is when i print it last week and other two is just been printed just now



thanks to @izzudinhafiz    for mention what kind of issue that my printer has several post b4

I think i manage to fix 70% my banding issue left cube is when i print it last week and other two is just been printed just now



thanks to @izzudinhafiz    for mention what kind of issue that my printer has several post b4

Guys! I need help. My extruder arent able to extrude a constant flow of PLA. what seems to the problem here? thanks in advance.

Glad you solved it. What was the issue causing it and how did u fix it?

That is definitely caused by z-axis wobble. Mine on the other hand you highlighted is not caused by z-axis wobble rather it is cause by over retraction from the retraction parameters.
Time to clean out your nozzle.

I dont know bout the wobble cause i didnt see any z axis wobble artifacts on the corner of my cube, so i think i got problem with banding issue

the banding is caused by wobbles. Idk how to simplify this. Its all related to trigonometry. A shaft that is not vertical is shorter than a perfectly vertical shaft. When the z axis wobbles, ie the lead screw rotates out of align, it creates an angled line (not vertical). Hence the position of the gantry doesnt move up as high as the slicer think it has. The banding is also periodical, because the lead screw is always out of alignment the same way every rotation!

FYI you can also have Banding on the X/Y axis, you can see wavy lines periodically.
It's obvious when running direct drive at high speed.

Eg:-
http://forum.seemecnc.com/viewtopic.php?f=37&t=7605&start=75

Does anyone know how much would a custom CNC/lasercut Acrylic cost for 3d printer casing ? maybe a 3-4mm thickness will do since it is just a cover.

So, was thinking on how to make my casing cheaper and then the ikea sale ad was on radio, then it struck me , anyone here made a casing out of ikea cabinet?

Thinking of using this
http://www.ikea.com/my/en/catalog/products...0246/#/20280245
and this as the glass door
http://www.ikea.com/my/en/catalog/products...3937/#/10273938

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