So I'm taking a break from my other projects and doing instead an OOB M1127 Stryker from Trump...I'm using medium green as I've read this is the best match but i was wondering if using black for a primer would be a no no? Any tips would be helpful...thanks

I don't see why you can't use black primer.
It might depend on how many hands of the main color paint you usually use later, and how far you go with color-modulation to hide down the primer dark shade.
I've used black primer in the past even in sand colored vehicles...

Ok thanks...I figured it would help for the shaded areas anyways so I'll be going ahead with it. I don't plan on any color modulations or anything else major so that's not an issue. I'm going to be dusting it up anyways so most of that would be hidden in the long run

I use black all the time to prime with. I suggest you try it on a small test piece first though, as it does have an affect on the color of the top coat.

I also use black as a primer, especially with darker colours such as NATO green.



It works well because I make sure to cover the entire model completely with the black, then when I paint the colour, such as green, you don't need to focus as much on the panel lines and undercut areas which gives it that pre-shading that I like.




cheers

well heres some an progress shot...still a little work to do

I also use black as a primer coat.
However, someone I know gave me a tip about using dark brown/burnt umber as a base for the more olive, yellow, or tan color coats, as opposed to the true greens or grays.
Makes sense, since it should provide a little less harsh of a contrast for those colors.

"Black" all the way. I use Floquil RR enamel black in various shades - some more a quite neutral dark gray.

I think it's pretty important to go into the primer and following base-coat colors with a plan to apply your base-coat variably and lightly (allowing some primer to show through), and knowing that a black or neutral dark gray can darken that base color, but won't really shift it in its tint, whereas other primer coats with color, such as "rot-oxide", browns, greens, etc., can change the base-color... so a red primer color may make a "dunkelgelb" or tanish base coat take on some browner tones in thinner areas, whereas the black will cause simple darkening in thinner base areas (simple pre-shading).

IF you plan on applying a solid (heavy) base-coat over that primer, the primer color won't matter, as it won't show through. In which case, use a primer only if you need one to ensure better base-coat adhesion to the build surface - otherwise it's just more paint to fill in details.

Cheers!

Bob

So why not primer the shadow zones in black and the sunlit areas in a lighter color shade of the final color? It should improve the scale effect.

Greg;

You could go that route - it's one of many alternatives!

It does, however, sound a bit complex to me... priming the shadow parts in black combined with priming lighter areas with a lightened shade of the base-coat, followed by, I presume, varying application of the base-coat over this shade-and-tint-varied base.

You can do a lot through simply pre-shading using the black only in deep areas, shadow zones, and in lines, and leave those lighter panel areas naked styrene, followed by varied thickness of base coat application. This MAY, however, actually alter your lighter base coat tint as the styrene color may show through rather than merely fading it to a lighter shade. Seems, however, that many folks do go this route, and if you are happy with the potential color tint shift in lighter areas, this is the simplest and quickest route to go.

Personally, I like to go the uniform black primer coat, vary my initial base application to allow some shadows and lines through, and follow up with spraying lightened base coat on exposed panels to get the faded areas.

That's the joy of the hobby - there are few "this is the correct way" techniques to get what you want - more a range of options a guy can play with!

Bob

You can check Jose Luis Lopez way of color modulation, using black&white for pre-shading.

http://dqscaleworks.blogspot.com.es/2013/05/the-black-technique-tiger-i-148-by-jose.html

http://dqscaleworks.blogspot.com.es/2013/04/guest-gallery-t-55-enigma-135-by-jose.html

More in PanzerAces #40,41

Calvin,
I ALWAYS use black primer for all my models. Period. Regardless of what color your base or primary color is. I use Rust-Oleum sandable black primer. I get mine from AutoZone.

Tony