"Tricks using different types of paint" Topic

I utilize a number of different types of paint and inks to get different effects, and was hoping to learn some new ones.

For example, when painting the black leather strapping on horses ( I always use the time honored method of heavily brushed oil paints for the animals) I use an acrylic grey base for the straps, and a heavy water based wash of black paint or ink, which congeals away from the oil onto the grey and into recesses.

For wooden gunstocks, various beige or yellow basecoats overlaid with brown ink, which again flows into recesses and permits less tedious picking out of metal banding and the weapon's sling.

Looking for uses of dissimilar media to achieve either better or speedier results.

I like to use Testors enamels for various needs.
It's a nice chestnut for horses, used with the Dip.
Gunmetal and matte steel are also good for weapons.
I like the yellow for thin lines on dark.

Watercolours are actually useful for black lining and even for all over washes. The binder (gum arabic) is water soluble even after fully dry, so you can clean up any errant wash with a damp swab or brush.

Though at the same time, you need to lock it all down. And you can't use a brush on varnish to do so. The varnish will reactivate the paint and make it run. So I spray on a matte varnish in two light coats. I also tend to do any water colour work last as the moisture or solvent in any other paint will activate the watercolour.