Linear bearing mod [ Printed bad linear bearings, fixed and added to the printer by PLA welding] This helped get rid of the skew in my x and y axis's without the need for the metal bearings.
New Plexiglass bed [ Replaced warped ABS bed with Plexiglass bed, works after a few prints then warps more so I recommend acrylic] Helped prints stick better and level my bed
Checked and lubricated Idlers [ Loosened Idlers so that they moved freely and lubricated them] Helped Skew
0 z-axis height for retraction [ Just put in 0 in slic3r/skienforge for z height under retraction] I had blobs of plastic forming during retraction so 0 z height fixed it.
Hose Clamp Tensioner Mod [ Use Hose Open hose clamp to adjust belt tension] Also helped my Skew problem Notice: Saw a BIG improvement after doing this mod
Replaced z-axis threaded rods [ Replaced the 1/4 in rods on the z axis] Helped get a constant z-height
120% Feed Override While printing [ I use EMC, There is an option for Feed override so I maxed it out at 120%] Helped me print faster.
Correct temp [Use the correct temp Very important] Helps to print faster, better and more solid prints
.2 Layer Height [ Set layer height to .2] Helps for faster prints, prevents layers coming apart under faster speeds.
This thread helps with other mods http://forum.seemecnc.com/viewtopic.php?f=35&t=455
Hope this helps
