I have a metal boiler / cab from a Riv 0-4-0 that I am stripping the paint and want to repaint it. I have had problems with paint sticking to metal bodies before, I did a MP FP7 up in Milw orange and the paint start flacking off the metal car body. I cleaned it with alcohol and then dish soap and rinsed well. I do use polyscale / tester model master acrylic paint. Do I need some primer 1st ? Anybody have some advice?
A primer would be best as it will give your finish coat some "tooth" to adhere to. For metal try good old auto body primer. I have used that on several metal kits with good results. Just be sure the paint is at least, room temperature.
Tamiya make a spraycan Fine Surface Primer that works wery well. It sprays a much finer coat than most spraycans. It is a bit pricey, bit the results are worth it. I doe a light dust coat first and then do one or two more light coats. Don't try to do it all in one shot. It's good stuff. Trey
Definitely need primer as others have suggested. Following the instructions, especially drying time between coats and final coat.
If you use a solvent-based paint instead and bake it, you don't need a primer. I painted some parts of my Treble-O-Lectric trains 20 years ago and they are still good. Baking enamel creates a very tough finish. Doug
Oh yeah, that too. One of the few advantages of being single. Also, I should qualify a bit. Whether or not a primer is required, even with baking, may be dependent on the enamel but I just used regular old PLA enamel and it got really tough after baking at about 175 degrees F. And clean the surface thoroughly with lacquer thinner before painting. Doug
Etching metal surfaces first before painting with a mix 50% vinegar & water for an hour or two. Breaks the smooth surfaces of metals. Paint will adhere and make a bound with the metal. Rinse with warm water let dry. Cast zinc shorter period of time.
On all my brass, metal, cast resin and plastic engines I use SEM Self Etching Primer. Comes in a 15.5oz spray can. Most auto paint stores has them I spray it direct into an airbrush bottle, and sit awhile to warm up before spraying. Only takes about 10 minutes to dry completely, then ready to start painting. I have been using it for the past 20+ years with 100% success on every paint job.
