washes.

I use Tamiya Acrylics almost exclusively so I can only speak for them. 

It is safe to use a turpenoid/artist oil wash over acrylics.  If I'm doing the wash over an aircraft model I will spray a gloss coat of Future (it's clear acrylic) to help the wash adhere to just the recesses and raised detail.  On armor I sometimes skip the future which allows the wash to also leave oil pigments on the flat surfaces.  All depends on the effect I'm trying to get.

If I remember reading correctly though, turpenoid/oil wash doesn't work well with enamels, so a lot of the guys will gloss coat with Future first before using that technique. 

i know there is a rule about the base paint then use differant wash base  but i always put a clear coat of the base coat prior to weathering so i really dont see a differance   i use both acylic detergant and pastel washes with no problem

thanks for the info. i appreciate it. any thinning of the future prior to airbrushing, or straight from the container?

I spray my Future straight on, with no thinning.

thanks again for the help

I use enamel paint and will sometimes use an acrylic wash from the artist tubes of paint.  Mostly I like a wash made from finely ground chalk pastels, I use a cheap mortar and pestle, water and a couple of drop of dish soap.  Compatible with all paints and washes of easy if you mess up.