erasing lines I seem to smear my gouache. I thought gouache
had a binder in it. Why does it smear and what can I do about
gouache is made from many diferent ingredients one of them being
gum arabic. Gum arabic is the gummy exudate from an acacia tree.
It is used as an emulsifier in many food products and an adhesive
or binder in inks, gouache, and watercolors. Gum arabic is water
soluble and can be reconstituted.
artists put the gouache into a palette and leave it do dry then
reconstitute it to work with. This gives some of the glycerine
time to evaporate and keeps it from being "gummy".
Designer's gouache is usually used to paint with and has enough
gum arabic for that purpose and isn't necessarily meant for
a rubber eraser scrubbing at it.
very helpful to try the color you want to use on the paper you
plan to use and wait for it to dry and then erase carefully
it smears then you should add one drop of gum arabic. I wouldn't
just routinely add a drop to every color unless you need it.
Too much will make it gummy and when it dries the gouache will
have hairlined cracks in it. Be careful when you are erasing,
don't scrub the lines off, but gently coax them off with small
strokes between letters.
into the habit of this and it will save a lot of work trying
to fix smears and wrinkles. The binder will be different for
various colors and papers. What works well on one paper may
smear on another. It's always a good idea to do your prepatory
work for any worthwhile project. It's saves times in the long
run and keeps from having to recover from unforseen problems.