How I learned to stop warping and love the acetone

Every since the first rhythmical hum of cnc plastic goopiness eminated from that beautiful laser cut, ABS spewing, Thing-o-Matic wonder; I have been at war against a warped (literally) and twisted foe. It seemed no matter my methods, my prints suffered from slunk edges, pulled up corners, and entire parts trailed about the platform by little plastic lassos. Attempted solutions were many; swapping out Automated Build Platform belts, constructing my own from Painters tape and Kapton tape, switching to the heated build platform, raising heat-bed temperatures, adjusting first layer feed-rates, etc.

While slowing operating feed-rates and reducing object first layer feed-rate multipliers in skienforge showed some improvement I was absent a satisfying solution. Even more mystifying was the predictable way warping started. First the front left corner would start to pull up, then the front right corner would detach, followed finally by the back to corners. And then the fateful day...

While experimenting with different Z heights, I laid some plastic so close into the kapton tape that even after peeling it out, a black ghost of plastic residue remained. On a whim I used acetone to remove the plastic and clean the bed. The following print stuck harder than a tar-pit on a Jurassic beastie. Realization slapped me across the face; oil. Every time I removed a print from the bed, oil from my hands were transferred to the platform. The front left got the most as my thumb moved to lift the part, the front right got hit second from the palm of my hand, and the back sides least of all. Respectively, the areas of my bed most touched suffered from the greatest warp and least stick. Further prints following a light rubdown of acetone confirmed my suspicions. Cleaning my bed with acetone after significant hand contact and before long prints has allowed me to print faster, at cooler temperatures and without warping. I'm sure there are you veterans in the trenches chuckling at my late cognition, acetone and cloth already tucked into your belts; but I am also sure there are many like me constructing brick walls closer to your bots so as to save the trip outside when you feel the need to bash your head against one. Your own mileage may vary, but if you've gone a few weeks without considering the effect grubby little mitts are having on your prints, give this a try. 

Here you can see the effect an oil-free printing surface can provide. Corners stay stuck to the build surface, as such you are able to turn the temperature on your heated bed down reducing interlayer warp tremendously. On the left you see a 20mm calibration cube (thing:2064) before I cleaned my bed; the right is the same gcode (reduced bed temp) after giving the bed a good acetone bath, the corners are flat and the walls are straight.

In brief, I have found these changes to greatly improv ABS stick and overall print quality.

1. Slow down - Long prints are better than no prints, the difference between 30 mm/s and 40 mm/s can be tremendous.
2. Level your platform - That first layer needs to stick evenly, a level bed is the first place to start.
3. Find a Z-height that works for you - Half my layer thickness off the bed has been a successful place to lay down my first bit of plastic.
4. Slow down first layer - Even during the dark days of warping this became a mighty weapon, I put my first layer down at 4-6 mm/s regardless of my operating feed-rate. This is allowing a great initial seal to your platform. (Nophead has in which he theorizing that vacuum suction plays a role, he also uses a slow first start)
5. CLEAN YOUR BED! - Depending on your printing material and bed this may mean something other than acetone, but I cannot express enough how much joy has been restored to my printing world after doing this. Do it. Love it.