electrospinning

Hi...i've been electrospinning recently but there is one frustration that keeps cropping up...the problem is that the polymer will not collect in a centered spot on the collecting plate...instead, it veers off to the side and collects there...this happens about 80% of the time...sometimes, the collection will occur very centered...we are using a horizontal setup, with a plexiglas chamber...would getting a faraday cage help with this off center collection? when spinning begins, i can see the jet veering off to the side...thanks in advance