I just got my first 3D printer. Monoprice Dual Extruder. It appears to be a clone of the FlashForge Creator Pro, as that is what Replicator G recognizes it as.

I have printed several smaller items almost perfectly. However I am trying to print the handle to a Lightsaber (http://imgur.com/a/Izo4s) (Files Here). Printing with PLA at 230° platform at 110°.

When printing the handle, I get beyond the knurling and into end/top that flairs out and up before tapering back in.
Capture.PNG
at JUST the point that it is at it's widest point (circled in red) the lip/edge begins to curl and warp. At the narrower part the extruding head keeps pushing it down as it ads layers. Once it is JUST at its widest it is wide enough that the second extruder can touch the part curling up. It nudges it so that the active extruder catches an edge and the object sticks to the hot metal and it gets dragged around and the print is ruined. (at 98%!!!! )

I assume the thin tapering edge is warping because it is cooling unevenly.

How can this be avoided?

I have taped a sheet of paper over the front of the printer to trap the hot air inside better. Should I do something similar over the top of the machine?

Any help appreciated!

LT.Son