I've damaged my paintings so many times by
leaving tape or masking fluid on for too long, so I hunted for ages to find
something to help fix/hide it.
...And then on one random forum some random guy
just said I take the back of a dessert spoon to it.
And it works, it doesn't fix everything but it
does hide a lot of the more mild damage...it's so simple.
So I did some tests, rubbing Sellotape onto the
paper then ripping it off and taking a blade edge along the top for some extra
roughness.
From left to right:
1. Just the damaged paper, for reference.
2. Just rubbing it with a spoon, works but
becomes slightly shiny and is easy to roughen again if you touch it too much.
3. Wiping water on with a brush, helps ever so
slightly.
4. Water sprayed on, doesn't do quite as much as
the brush.
5. Water sprayed on and then rubbed with the
back of a spoon, this works rather well but not as good as:
6. Water rubbed into the paper a bit with a
brush and then the back of a dessert spoon. It did smudge the graphite of my writing
a bit but on clear paper you'd be fine. Not sure how this would work with paper
that already has watercolour on it. It also does still roughen up slightly if
it's handled too much so you may need to fix it up again at the end of your
painting.
Now the bottom strip was testing with some Pound-land
PVA glue, not something I'd use on an actual painting at all. Research your glues.
It also wouldn't take anymore paint on top later, there is a watercolour medium
out there that lets you use watercolour on top of anything; I imagine that
would work well. You just need something ever so slightly sticky to dry on
it.
And the glue worked really well, I did three
different thicknesses mixed in with the water and you really just need the bare
minimum to stop the paper roughening up again when rubbed.
But yeh, don't use cheap PVA glue on real
paintings, get something that might not change colour or crack with time.