House paint as primer

I'm thinking probably not. I would expect that housepaint primer is probably formulated to adhere very well to drywall and wood, but not plastic. I tend to use one of the (yes, too expensive) Tamiya primer spraycans for my stuff. I've seen others posts speaking of various cheaper options but I can't say that I've used them before. Keep an eye out, you'll see some more answers!

NO! Please do not use house acrylic paint on your models! If you must try spray can enamel red oxide primer that is compatible for plastic.

Try on a piece of wood first, if the grain and detail show well on that then practice on a old model first. Start and stop past the model, be fast and remember less is more, apply a second coat after dry if needed. Once to much paint is on there is no going back. Some tight areas may not get any paint, avoid temptation to try and reach these areas with the spray can. Hit nooks after dry with a brush instead.

A regular can cost the same as a tiny Testor's can so it is more economical. Red oxide primer is found in the automotive section of most stores, Krylon and Plasti-coat are good brands.

As a primer, no. I too use Tamiya in the can. It's the best I've found after many a trial and error. I have used house paint before, in a case where on my model railroad there were five stations I scratchbuilt that had a common-standard color. The only reason was because I could not find a Polly Scale color, I had a chip, so off to Ace and they mixed me a quart. But it cost 10 bucks, and I probably used 2-3 ounces, so it didn't really save money. but it worked.

No.

Acrylic house paints are formulated to form a thicker film, and contain much coarser pigments than hobby paints. They are also formulated to stick to common house materials: wood, plaster board, etc., and generally don't bond well to plastic.

Some general purpose aerosol paints may work, although the acrylic ones are still highly problematic, IMHO. Aerosol paints are generally formulated to form thinner films and have finer pigments. However, some aerosol primers, particularly those for automotive use, form very thick films so they can be sanded.

I also find house paint a very thick paint and would not use it on a model. I use duplicolor or Krylon primers for either enamel or acrylics (in spray cans) and they are not too expensive.

I only use Floquil Grey Primer enamel, applied with an AB.  Household Acrylic/Latex paint is way too thick.  If you must use a spray can, try Krylon Fusion which is formulated for plastics.  I've used it on vinyls with good results.

Regards,  Rick

I use krylon primers all the time.  I have a can of black, red and grey, depending on what my top coat color will be.  Heck, if I'm doing a large, monochromatic color, I even use krylon spray for the top coat as well.

It's fine enough to not hide subtle details and dries to the touch in 10 minutes (but give it a few hours before you start knocking it around).

Here's a build I'm working on currently.  Primed with krylon grey primer and topped with krylon flat black (the miscellaneous different colored panels are on purpose, not a goof of the paint)

-Fred

I use duplicolor sandable automotive primer, available in most auto parts stores.  It sticks well to metal, plastic, and resin, sprays a nice fine mist with no clumps, and is sandable! 

Chris

Thanks everyone for your very helpful reponses. Your are all the greatest!!

tried it once   actually 3 times latex   oil   acrylic

oil never dried right crazed the plastic

acrylic could never get thin enough hides every tiny detail  looked like a kindergarten paint job

latex  peeled right off after drying

IF you have an airbrush, you could try Alclad's grey primer / microfiller ALC-302. It comes ready thinned in a 120ml container.