[Gimp-user] erode only "thin" areas

[Saara <forums gimpusers com>]

Hello,

Is there a way to erode (or something similar) only thin parts, but keep thicker
parts intact?

I have a line drawing on a graph paper. I would like to keep all the drawn lines
and make all the graph paper lines disappear.  If I use erode, it chips away too
much of the line drawing. It is not possible to distinguish the lines with
colour as the colours are too similar. It would not be easy to select the area I
want to keep either as the line drawing is huge and intricate and obviously
intersects with the graph lines allover. My drawn lines are around double the
width in pixels with respect to the graph lines I would like to get rid off.

Thank you!!!

-- 
Saara (via www.gimpusers.com/forums)