What is a primer

Hi;

 I won't use all of it , But , " To Prime - To prepare a surface for Paint or an individual to do a deed , or a fuel system to provide fuel etc  " . A prime coat does more than most of us think .

 On the molecular level it fills small unseen divots and flaws , But the main idea was to provide a surface that had " Bite " to the surface being painted . It grips the surface on the molecular level and becomes one with the surface material .

 If you could see prime coats through a microscope it would look like a chameleon's foot . Gazillions of little hairs or fuzz gripping the surface , right down to it's pores .

 And then the next coat makes it , by chemical reaction , do a tighter job to both surfaces .      T.B.

I too recommend priming. Shows the defects and gives grip. No peeling from masking now. I use the polyurethans airbrush primers like AK and Stynlrez. I use them straight at higher pressure. Really great. Clean up the airbrush with denatured alcohol, a sovent cheap at the hardware store. Works great, cleans fast. Dont use Windex to claen it up and you will be golden.

I always use primer but my go-to primer is Rustoleum gray primer. It's a matter of preference really.

Hmm, all good info for me at least. I never use primers in model building except in select repair areas. Maybe it's time for me to try primers overall. I do seem to have paint pull-up problems when masking.

Watching, listening, contemplating and considering. Thanks for everone's input on the subject, the Forum is a great place for all this I'm finding out!

Max

For many years I painted and rarely primed the surface, I only used primers for a coat that would allow me to sand it for a smooth surface under paint. I didn't often have lifting problems while pulling masking tape, maybe because I always carefully washed and rinsed the plastic before assembly, with a thorough wipe with clean cloth and alcohol before painting.

Now I find a good primer coat gives me a hard and durable surface, that sands easily before paint by just using a 1200 grit polishing pad. It also gives me a surface that clearly shows any faults in my preparation of the plastic joints, or filled repairs. Much better and easier for me to make any needed corrections, prior to the finish coats being sprayed on.

I had good results from some of the commercial spray can primers that were sandable, but they seem rather inconsistent now, as I think they may make frequent formula changes that alter the results.

For some time I have mostly been using Badger's "Stynylrez" primer for acrylic paints, and Alclad's primer for painting with their lacquer metallic finishes. Either gives me very good results, and I have had zero lifting or final finishing flaws using them routinely.

But there is no absolute rule that says you can't get a fine finish without using a primer, Plastic Junkie and others turn out some perfectly beautiful work without priming. As always it's an individual choice, by trying it both ways, prime coat or not, you'll determine which is right for you.

Patrick

theflyingdutchman

What is a primer and what is it used for (benefits)?

Good question! The word 'primer' is a noun, borrowed from Latin 'primus' meaning "first." Some people misuse 'primer' as a verb, but no one seems to care.

A primer is simply a type of paint that is meant to be applied directly to a substrate to prepare the surface for painting. Primers should be formulated to help the top layer(s) of paint stick better.

A 'surfacer' is a type of paint that is meant to help level out minor defect, and can be sanded smooth. Hence the name, 'Mr. Surfacer.'

I prefer to use a combination primer-surfacer that does both. But the lable won't say 'surfacer,' it may say 'sandable primer' or something similar. My favorite is the primer made by Alclad II, it dries fast and sands well. It is a lacquer so it requires extra safety precautions.

Use of a primer is not absolutely necessary, but it does help with acrylic paints, especially if you will be applying masking tape. I almost always use primer.

I painted for years without useing a primer, and that included useing resin and PE. Now i will prime most of my kits unless it is such a goodfit that i didn't needto fill or sand. A dark primer can hyelp with the weathering process and a light one can help if useing light colours such as white or yellow.

In short, no you don't have to. I use Alclad lacquer primer which comes in white, grey and black.

Primer gives paint some bite for better adhesion. I personally use primer only on resin, pe, multi colored kits, and on puttied areas. In these examples, the primer will help in providing an even top coat color and texture. Some minor scratches will get filled too. These are the only times I spray primer on otherwise I see no need when no fillers are used and the plastic is one color. Some modelers will primer the entire model regardless so it's up to the individual.

Tamiya makes very good primer both in white and grey. Alclad makes grey and black primers, both are excellent. Mr. Surfacer 1200 is also very good.