I’ve just completed the tiny Moebius Robot from Lost in Space using Testors enamels (which is unusual for me). Normally I’d use Tamiya Panel Liner for picking out details and accenting lines on acrylics, but it’s an enamel itself and very conspicuously states “do not use on enamel” on the bottle. That being said, wouldn’t a standard oil wash (thinned with white spirits) also attack enamel? I’ve got a Vallejo acrylic wash on the bench as well. Thanks! - Blake
Yeah, I’d expect the white spirits to attack the enamel. I use white spirits to thin enamels and clean my brushes when I paint them.
I use mostly water-based acrylic washes, anyway. I don’t use Vallejo, but I use a lot of craft-store water-soluable paints in water washes, and I’d use them in this case, too.
If your enamel base coat has dried and cured, you can do an oil wash over them if you use a mild thinner like Mona Lisa brand. I’ve done that numerous times with no ill effects. But that is the only brand of thinner that I can will work for this method.
If looking for something premade I have come to really like the “shade” series from Citadel. They work over any finsh and have several different colours. You can usually fond them at places that sell gameing supplies

A few years ago, I switched over to Flory washes and haven’t looked back. No messing around with clear coats and hoping that enamel thinner doesn’t burn through them (which it often does). Just glop the stuff on with a big brush, wait about a half hour for it to dry, then remove the excess with a damp sponge. Its water/clay-based so it doesn’t attack anything. You can even forget about it and leave it on your model for months and it will still come off when you decide to take it off. Zero risk to the paint and decal work that you spent hours on.
I make my own washes anyway,mostly acrylic washes, some oil stain/water clean up ones too. Over enamel I’d use acrylic personally.
How about sealing it with an acrylic clear coat,I’m thinking that will protect what’s under?
I’ve thinned oils with turpenoid and done washes with no impact on enamels. But these days I too am totally in with Flory washes. They are completely inert and sooooo easy to use.
Thanks for all the replies, folks. I ended up giving The Robot a couple coats of PFG and then a wash of artist’s oils and Mona Lisa white spirits. I’m happy with the results. I’m intrigued by the Flory washes and will check them out, too.