Polytene squashes

[Allison Stelling]

Hello! My name is allison and I am doing squashes with drosophila
larvae. The arms are spreading fine, but they keep coming out partialy
of fully refractal. Does anyone know where to find protocals?  does
anyone know a better way to spread than banging on the cover slip with
an eraser? and does anyone know a better way to squash them than with
their thumbs?
thank you,
allison