Vallejo Primer Help

I use Vallejo exclusively. The primers I usually use straight out of the bottle at first, if I notice it is drying too quick on the airbrush tip due to climate conditions I will add a drop or two of Vallejo thinner. I also keep a little water or thinner dampened Q-tip to clean the airbrush tip for longer painting sessions, 10 to 15 mins or so. Hope this helps.

blackburge

I also want to know if someone as used Tamyia Flat base XF-86 with airbrush. The same question, should I cut it with thinner?

Tamiya Flat Base (X-21) is an additive which is mixed with gloss paints to make them flat. Do not attempt to use this as a flat clearcoat, as it will only result in covering your model with translucent white frosting.

You can mix it with X-22 clear gloss (approx. 1 part flat base to 4 parts X-22 before thinning) to make a flat clear, but it's probably easier to use XF-86 Flat Clear. 

Get some Vallejo Airbrush Flow Improver,a few drops stops that tip drying

Does the airbrush flow improver work with clear coats?

i use it striaght from the bottle also. i used to thin it slightly with vallejo acrylic airbrush thinner to use it in an airbrush with a smaller needle set. It had a hard time spraying it and sometimes had tip dry.  Now I use a Badger patriot 105 with the large needle set and it goes on great right from the bottle, no tip dry. I think using a .5 or maybe larger needle set is the key. Great stuff though.

And what about XF-86 Flat CLear with airbrush? Should I use thinner with to spray with my airbrush or directly from bottle? 

i use it straight out of the bootle but not as a primer. i prime with Ace Hardware NOW and then us the Vallejo primer over it. thinner than the Vallejo paint so i get some nice shadow effects. stumbled across this doing an OTS T-55 mine roller. one of those mistakes that turned out nicely. took a first at a regional with it.

I use Vallejo Primer straight from the bottle too, but always use a larger sized needle/nozzle. I find it does tend to gunk up. As for flat base - what Phil_H said. It's primarily used to get rid of the gloss finish from paints that may not be made in matte. When i first got back into modelling, i used to us it, but now i just do a matte clear coat at the very end. I can't really tell any difference.