Today I started priming my Dragon Sig 33/1 Grille that I have spent sooo much time on( link to pics https://armorama.kitmaker.net/forums/180572&page=1 ) , and lets say it didn't go so well!
First of all I my Tamiya superfine primer had run out, so I decided to try out some automotive primer I got from hardware store. I tried it on my brass ammo shells first and it came out pretty good.
My grille is in 5 different assemblies so I began priming each one. After 1 coat I guess I rushed into another one shorty after, and I put it on a little too thick.
After I primed all the assemblies I noticed that 75% of what I sprayed was crap!!
I have been so patient building this thing why in the world did I rush the priming!?!?!
I spent the next couple hours removing the drying primer with mineral spirits. Which was not easy with all the small photoetch parts everywhere! I do have to say how impressed I am how everything held together from all the solvent I doused on the model.

So I am letting the model thoroughly dry, and I am going to buy some new primer. Do I stick with some Tamiya spray primer, or should I try some Vallejo's new primer? I have never used it before and was wondering how it holds onto white metal, and photoetch.

Can anyone who has used both types of primers give me their suggestion?

Thanks, Nathan

I seems to always go back to Tamiya. I have also used on occasion the new Vallejo primers through my airbrush and I seem to have good luck with them.

Now at times, I have used Testors Spray can when I was in desperate need. Usually a grey, or other lighter color.

Nathan, with all the work you put into that one...stick with what you're used to, the Tamiya primer. Save the experimenting with new products for something less involved

Nathan,
Next time you have to strip an enamel primer, fill a plastic tub with DOT 3 brake fluid and submerge the model. Leave it overnight and the next day the paint will be gone. Rinse with water and you've got squeaky clean plastic ready to start anew. If you need to strip acrylic paint, use the same procedure with Windex.
You don't always have to prime a model. It just has to be clean. Modern acrylics adhere well to styrene, PE, white metal, and resin very well. What I do is spray the model down excessively with Windex, really soaking it all over, in your kitchen sink. This melts away all the mold release agent, oil, skin oil, dust, dirt, and crud without having to touch the model. Then rinse it down with the sink sprayer, put it in a tupperware and let it dry. Your paint will go on perfectly.
If you want to prime, this vehicle will be finished in Dunkelgrau, so I very highly recommend the Vallejo Dunkelgrau colored primer. Primer and base coat in one, and it's just outstanding paint. You just can't do better.

Nathan;

I'll second Matt on the prep step - wash the build (Windex is great, mild soap water followed by good rinse with distilled or bottled water good. Dry is essential for next step).

I'd suggest "Priming" with a fine-grain enamel: As I like to "pre-shade" my stuff (specifically to get ahead on those lines and small shadowed places behind and under stuff, holes and wells in things, etc., and to ensure that the color transitions from PE or other materials to adjacent styrene are masked), I always at least partially "prime" with a dark enamel - I use Floquil RR colors, or sometimes ModelMaster. This always adheres super well to the PE and to the styrene, and is a THIN prime coat. (Rattlecans have always gone on too heavy for my tastes... but that's me). And it gives a thin, clean, RESISTANT and STABLE base for the follow-on acryls (or more enamels, if that's your druthers).

Cheers!

Bob

Ive heard of the windex before, but never the brake fluid. Its okay to do this on a built model without it messing with the CA glue? I am worried that it may soften the plastic.

I've done it myself and it doesn't loosen CA or soften plastic.

I'm a old school modeler, and prime before painting. Primer has one main function, to adhere to the plastic surface, and at the same time be a superior base for paint to adhere to.

Primer isn not paint, and paint is not primer.

I've used several model paint primers, and none are in the class of Tamiya's Grey surface primer, which is lacquer based,

I got myself a bottle of brake fluid and tried it out on some spares, and you are totally right! Not that I didn't trust you but I just wanted to make sure that I don't screw up my Grille any further!
Right now she is taking a nice bath, awaiting shipment of some primer, I ordered both but I am planning on putting down Vallejo black for preshading.
Thanks for the awesome tip, wish I knew it before I blasted thinners everywhere!

You're welcome Nathan. I never give advice, a tip, or a suggestion unless I've done it myself on one of my own models. I've been at this hobby 43 years and I'm still learning new things but it's amazing all of what I've picked up along the way. That's how I got this cushy high profile job as host / moderator of this forum!

Finally got the grille all cleaned up and put back together, nearly all my photo etch parts came apart from the thinners, or brake fluid, or combination of both. Either way it gave me the opportunity to clean everything up pretty good.
Last night I put down some Vallejo grey primer and was extremely satisfied with the results!! I would say I like it more than the Tamiya aerosol primer, because you do not have to worry about the fumes. I did not experience any problems using it with my airbrush, as others seem to have.
Next couple days ill lay down some preshading and get the base coat down.