Solved Rounded corners on all prints, Y Axis drifting

I was wondering if someone can help me with this issue. Every objects that I'm printing have like rounded corners. I've checked the belts and my e-steps and they are both are OK, belts are tight and e-step is calibrated.
Someone also told me to enable "Advance Algorithm" to see if that fixes the problem but it didn't.

 

Probably a slight over extrusion and/or printing too fast. Try to calibrate the extruder and slow down a bit.

But all corners in the x-y plane will be slightly round. It is the nature of the printer.

 

I'm printing at 50 mm/s, I'll try to slow it down more.

 

Yeah I rarely print above 35 mm/s. I only do that when I don't care how a part looks.

 

Don't discount the extruder calibration.

https://www.google.com/url?sa=t&rct...=_83CDBVsfMR-cO_KhBNw3g&bvm=bv.89381419,d.d24

 

I never print below 60mm/s its all about fine tuning. in your case, over extrusion and slow around the corner..
it oozed too long/extruded too much in one spot.

The only thing you get printing below "fail speed"* probably about 100mm/s on a well maintained robo, is reduced ringing. And In my tests, ringing only reduced noticeably below 30mms but it got horrible at about 90mm/s but that depends on what you're printing and what finish you desire. some things don't ring, other things ring for days.

You can also run into stripping problems on your filament if you're printing too big too fast.

Tuning consists of the above extrusion calibration, ensuring proper tension on belts (trial and error really), proper lubrication, tightening of screws, bracing of z rods, software calibration (slicer/front end stuff), and good set up (enclosure, clean platten with proper adhesive {hairspray})

*Fail speed is where there is noticeable degradation in alignment of the layers and general aberrant deposition behavior. For things that don't need to look pretty or have super tight tolerances, 120mm/s with a slightly slowed acceleration (900mm/s/s) will print fine if you're well tuned. I've printed up to 240mm/s but It probably would kill the machine quickly and quality definitely suffers.

 

I printed some test objects at 30 mm/s and it seems to work. I haven't got any rounded corners.

So I've decided to print a dock for my phone and I ran into some issues. The first 8 hours were ok but things went fubar on the last 2 hours. It appears that the y axis drifted. I'm printing this. http://www.thingiverse.com/thing:559747

 

http://community.robo3d.com/index.php?threads/visual-troubleshooting-guide.3017/
Looks like you got some tight binding parts. Find them and sacrifice them. Or oil them. Whatever ends up working. Are you using lm8uu bearings or plastic? I had the same thing happen when I tried to use PET as a linear bearing.

I come from a position that, If I can drive to the local printing shop and have them print it on their makerbots then drive back during their business hours and pick it up faster than I can print it, MY 3d printer is broken. 30mm/s is unacceptable as a standard under almost any circumstance. Faster is always better in manufacture. Just have to make the process support it.

 

I've checked everything and they looks OK, both x and y belts are tight, axis are oiled up and I'm using the lm8uu bearings. About the 30mm/s, if I got about that I start to those rounded corners.

 

The Y axis belt is pretty tight. I was wondering, is it possible that when the stepper motor gets really hot it might lose some steps?

 

The magnets will demagnetize around 80C