Never. The paint will not adhere properly to a waxed finish. You may get products from your local jobber that will help remove wax and properly prep the surface before painting. They are an excellent investment
If it has a matte finish it should be easy to paint over.
Yes. You can paint semi-gloss latex paint over flat latex paint. It is not advised to paint over any latex with any oil-based paint. Nor is it advised to try and paint over semi-gloss paint with any other finish without first de-glossing the finish and priming.
Primers are not water proofers, in fact primers can't be left as the finish coat because they have no durability. If the paint acts as a primer how can you expect the paint to stand up as a true finish coat.
Spray paint does not adhere well to waxed paper because the wax coating creates a non-porous surface that repels paint. This results in the paint likely beading up and not sticking properly, leading to smudging or running. For better adhesion, it's advisable to use a different type of paper or surface that is designed for painting.
The paint finish doesn't significantly change the surface preparation necessary. If the paint is the same type (water based going over waterbased or enamel over enamel) then the preparation is simply: * cleaning, * remove loose material, * fill any holes or hollows, * sanding and * wiping, If you are changing the type of paint (eg: painting waterbased over enamel) you may need to use an etch primer to "key" the surface and give the new paint a texture to grip onto after sanding, and otherwise prepare as above.
If it has a matte finish it should be easy to paint over.
Yes, you can use polyurethane over paint as a protective finish.
Yes, you can apply lacquer over paint to achieve a glossy finish.
Yes, shellac can be used over paint as a durable finish.
Yes, you can apply lacquer over paint to achieve a glossy finish.
Yes, you can apply polyurethane over paint to provide a protective finish.
Yes, you can apply polyurethane over paint to create a durable finish.
Yes, you can use lacquer over paint to achieve a glossy finish.
Yes, polyurethane can be applied over paint to provide a protective finish.
Yes, you can use polyurethane over chalk paint as a protective finish.
Yes, you can spray lacquer over paint to achieve a smooth and durable finish.
Yes, you can apply polyurethane over paint to create a durable finish.