Qidi Tech 1 - Replicator 1 clone

[sygyzy]

Hi guys, I have a bit of a weird problem I could really use your help with. My QIDI 3D Dual Extruder is having issues printing in the center of the bed. A little background - a few months ago I removed the factory blue sheet that was on the heated bed. I replaced it with a 1/8" pane of glass from a local framing shop. The glass is not the exact size (slightly too small), and I am using four corner clips to hold it in place. It's pretty stable. Sometimes I use a binder clip on one side. The heating is fine. I am printing exclusively in PLA on the right extruder. The left extruder has no filament and the nozzles were recently leveled.

Anyway, the issue is any part of the model that is roughly around -50mm to 50mm on the X axis gets no filament laid down. In other words, if I were to draw a straight line, you would see a light gap in the center. I've gotten around this temporarily but positioning my models towards the corners of the bed but this is not the best solution since some models are very large or very long and need to cross the origin. I know this sounds like a leveling issue and I've leveled, I swear, over a dozen times already. I am not sure what else there is to do. I suppose it's possible my glass isn't flat but ... that would kind of go against the definition of glass - it's supposed to be perfectly flat. I ordered another sheet - 3mm borosilicate and that's arriving this week. Maybe I'll have better luck.

Any ideas in the meantime?