Painters,

I'm building the Tamiya 1/25 Tiger in Dunkelgrau.
I intend to use the brush & sponge technique for surface
scratches. What color should/could I use for this?
Thanks for any advice you can give.

ASLmodeler

I use Tamiya NATO Black.

I use Modelmaster Gun Metal Non-Buffing.It's a matter of preferences I guess

Thanks. I'll give it a try.

I appreciate the advice.

Maybe a lightened version of the base color?

Are these scratches deep? To the bare metal? Or are they just surface scratches, in the paint itself?

Could be both. What do you recommend for either?

For light scratches that didn't penetrate to the metal use lighter shade of base color.
For deeper scratches first apply lighter shade of base color as an outline of a scratch, then paint the inside of a scratch with something like gun metal or black metal color.
If you want to go really crazy and can paint really thin lines, apply lighter shade of base, fill with red brown primer color and black metal in the middle.
Practice on scrap plastic, it's really easy to overdo it and make a lousy job.