Do Primers Live Up to the Hype?

I can’t comment on Vallejo primer, as I’ve never used it. But I have used Humbrol, Tamiya, Mr Surfacer, and AK. Each has their own virtues and vices. All of those have been good products. I’ve never had any luck hiding flaws with primer, but have found all sorts of flaws needing correction that I thought that I’d corrected.

With all respect, I've never heard that primer is supposed to hide flaws or bad sanding; one of its prime uses (no pun intended) is just the opposite, to show up surface flaws that are otherwise tough to see on monochrome plastic or mixed filler/plastic areas.

Lacquer primers are generally the most versatile and durable as an undercoat; acrylic primers seem most useful as a 'color' base to go under light paint colors or to cover multi-tone undersurfaces.

That having been said...I prime less and less these days...just as a time and effort saver...and see very little difference in either the quality or appearance of my finished models. Maybe that's down to better-quality modern paints. (I use Tamiya acrylics almost exclusively.)

I always prime. It will show you flaws before applying paint so you can fix them, It adds a smooth base to apply paint and I have had zero paint pull up when masking if I use primer. I have used Mr. Surfacer, Tamiya surface primer, Badger Stynlez and Vallejo. I like them all. The Vallejo and Badger are latex based. They need to be thoroughly dry to sand, (2-3days to cure at room temp. is plenty) or I simply hit it with a hair dryer when done until dry and it will only need overnight. I find it worth the effort and expense to help me see better where I need to fix an issue bfore paint and to get a smooth strong paint finish.

modelmaker66

I have used Mr. Surfacer, Tamiya surface primer, Badger Stynlez and Vallejo. I like them all. 

I rarely use primer for aircraft kits unless I am doing a NMF, then I ususally use mr surfacer 1000 as a base coat for alclad. It does also fill 'minor' scratches, but mainly it is a base coat for the Alclad to stick to.

For inspecting my sanding work, and finding flaws in seam filling, I just use a silver sharpie (best tip I ever got from FSM Magazine...).

Also, I have tried using primer on the leading edges of wings and stabilizers as paint always seems to pull up in these areas, but frankly, It does not seem to help.

Tamiya Spray primer is great stuff I will say. And will definately fill scratches if enough is used. I use it mostly when I dabble in model cars -- which is not often...

I have used Mr Primer,but prefer Mr Surfacer 1200 in the rattlecan,not as heavy,levels nicely.I use it primarily for better adhesion,resin and metal painting,and seam checking.

Never felt it was some magic bullet cure all.

stikpusher

I can’t comment on Vallejo primer, as I’ve never used it. But I have used Humbrol, Tamiya, Mr Surfacer, and AK. Each has their own virtues and vices. All of those have been good products. I’ve never had any luck hiding flaws with primer, but have found all sorts of flaws needing correction that I thought that I’d corrected.

 

In my own personal testing of a particular primer conducted over 18 months with lacquer nail polish, enamel and especially acrylic top coats, every category I tested for went better with the primed surface. So this is not hype just casual observation and home tests of specific functions of the primer I wanted to switch to. I did the tests prior to painting model parts by spraying days ahead onto prescription bottles ( the amber ones you get from the pharmacy). I was especially surprised at how bad some trusted paints did on bare plastic in terms of color casts, spectral and odd glowing from under the paint in certain colors and scratch testing on the semi translucent plastic. Really bad results on the bare plastic turned good or decent with a simple thin coat of primer well dried on the surface before top coating.

There was a time where I could take or leave primer on models, though in 30 years of 1/1 painting bare materials priming was/is the standard ( you would be hard pressed to drive in, fly in or shoot armament from any kind of painted vehicle that wasn't first primed).. I then for a long time usually sprayed lacquer rattle can primers on model parts. Sooo, but now I have come to always prime bare plastic after my own testing revealed what it showed to me. The exception being things like tail light lenses, canopies etc. that might get a clear or clear color put on and still be able to see through it...

Paint does not cover up a multiple of sins :-)

A full bodied primer like auto body primer, can cover tiny scratchs, like those from 320 sandpaper.  But more importantly, primers add adhesion and gives a visible surface.  Styrene is somewhat translucent, so you are seeing slightly below the surface, say a mil or so.  A truly opaque primer shows you the actual surface.

While you can get away without priming styrene, I find it easier to paint if I do.  Once you have sanded with something in the range of 600 - 1000, you are ready for paint.  Paint will give you a finish that does cover the scratchs from that range or finer.

Niko

People will tell me that primer will hide issues and rough sanding. Primer will reveal mistakes and somehow at the same time correct a lot of mistakes made on the model. Essentially, primer is the Holy Grail and will solve all your problems ... or is it?

Not sure who you have been listening to, but that is all absolutely wrong. It's what Stik said: "I’ve never had any luck hiding flaws with primer, but have found all sorts of flaws needing correction that I thought that I’d corrected.". I also agee with MM66's comment "I always prime. It will show you flaws before applying paint so you can fix them, It adds a smooth base to apply paint and I have had zero paint pull up when masking if I use primer.". I almost ruined a 6 month build with paint pull up on a non-primed surface, and I also prime just about everything.

I don't know if I'm doing something wrong with Vallejo Surface primer, if I got bad batches, or what, but I find the stuff next to useless. Drying time is unreasonably slow and even then it is not sandable. It does cover nicely and self-levels and makes details pop wonderfully, though.

I think your thought process is right, try a good primer. You mentioned Mr Surfacer, good choice. I find it stinky and messy to work with and don't use it much anymore in favor of Badger's Stynlyrez. If you want to very easily learn how a "real" primer should work, buy a spray can of Tamiya surface primer and test it out.

That said, I've yet to find anything Tamiya can do that Sylnylrez cannot.

I agree with everyone here,

I use Vallejo myself and really don't care about the drying time because I have so many kits on the bench at any one time. I always black base, unless I'm painting white or yellow. It just seems to work with my style. I have tried most of the other primers and they work well too.

I have to agree wholeheartedly that they show more areas that need attention than anything, and that's perfectly fine with me.

I have always primed.  Ask any body shop guy or gal and they will tell you that it is insane to NOT prime.  It does show flaws that you will not be able to see with out it and it gives the actual base coat color something to "bite" into.  Bare styrene is too smooth to allow most paints to bite into them.  With that said...........

I have used Tamiya's primer and i love it (I love all things Tamiya!) I have not used Stynelrez or the Vallejo primers.  I use Vallejo paints but i am slowly transitioning over to all Tamiya Acrylics as they are just much easier to work with.  I alos use Krylon primer from walmart.  The Krylon has to be applied in a specific way but works great dries within 2 days and is cheap. 

Bottom line....Prime everything you paint, Use a decent primer and you will not be sorry. It will show your flaws (If any) and allow you to get a much better paint job. You will not be sorry. 

Niko

...People will tell me that primer will hide issues and rough sanding. Primer will reveal mistakes and somehow at the same time correct a lot of mistakes made on the model. Essentially, primer is the Holy Grail and will solve all your problems ... or is it?...

First and foremost, a primer is used to improve finish color coats' adhesion to a subject.  Anything else is secondary.

"Primer will reveal mistakes."  That is generally true, that when you apply a coat of primer to your model, it can help make surface mistakes more visible.  This is common among figure painters, for example.

"Primer will hide issues and rough sanding."  That may be true, especially if you use a thick primer, or apply a thick coat.

But as I said, a primer's purpose is to improve finish color coats' adhesion.

And as someone above posted, it's crazy not to apply a primer coat.

I use Tamiya's Fine Surface Primer, myself, and I've also used Rust-oleum and Walmart's house brand automotive primer, all in rattle cans.  Tamiya's is fine, and lays down in a nice thin coat.  Rust-oleum and Walmart's automotive primer are a little thicker, in my experience.

modelcrazy

I use Vallejo myself and really don't care about the drying time because I have so many kits on the bench at any one time.

Does it sand ok for you, Steve?

My suggestion and that's all it is, is when your Vallejo is running out get yourself some Stynylrez. It dries in minutes vs days, it's also a poly acrylic like Vallejo but sands better and sooner ( many times I've put down the base color coat the same day I shot the primer). I actually turn it to a satin finish using 000 steel wool, dry scuffed. And that makes a difference in your final color finish, especially with gloss paints. To me that's about the difference between using it vs lacquer primer where you have the option to wet sand the lacquer. And it doesn't stink the house up. Oh and it really doesn't go on dry and self levels anyway if you have your pressure off a bit.

I can't vouch for Stynylrez in use on resin models though for those who get into that, I haven't tried it. Someone else maybe will comment on that.

oldermodelguy

My suggestion and that's all it is, is when your Vallejo is running out get yourself some Stynylrez.

Thank you, I will pick up some Stynylrez and try it out!