Q: Do you sand your furniture or use liquid sander?
A: I sand it with my sander that goes into corners and also has a rotary head on it as well. For the spots that the sander can't get to, I sand by hand. Just a little scuffing to take the sheen off it all I do.
Q: What exactly is the poly coat for? Does it make a big difference in the final look?
When I refinish a piece of furniture I always use a polyurethane over the paint. Most of the time, in a satin finish. It helps protect the paint underneath it. It will not scratch and wear as easily when you put a poly over it. It gives the piece a bit of a luster that a professionally finished piece would have. It looks much better than just paint by itself, and of course it's more durable. Its like hairspray is to hair, not totally needed but it finishes off a look much better with it.
Here is a Before polyurethane and an After Polyurethane picture: You can see the wood underneath shows through a bit darker, also there is a tiny bit more sheen to the piece.
Q: Do you use a sealant sometimes and a poly others?
A: No, I've never used a sealant.
Q: What kinda of polyurethane do I use over my painted furniture pieces?
A: Minwax Wipe-On Poly in Satin. This stuff is great. You pour a little on a soft clean rag and rub it all over. Its great for little nicks and crannies. It leaves a nice sheen, and highlights the wood that shows through the paint on distressed pieces. Since it's wipe-on it doesn't leave any brush strokes, and it dries pretty fast. It also comes in gloss, but I prefer the satin on most things.
Q: Does it matter what kind of paint you use, and what kind do you use?
A: It matters to some degree I think. A better paint is going to go on smoother and with more pigment. Good paint wears better over time as well. I like to use Sherwin Williams the best. I like the sample quarts from SW, they come in a hard plastic jug with a handle and a large screw top. They are great for holding while dipping your brush in, no need to transfer to a separate pan with SW quarts. The nearest SW store is about 20 minutes from my house, so when I'm not up for the drive I go to Lowes and get Valspar. I like how Valspar has the National Trust Historic Paint Colors marked on their paint swatches. I tend to really like the colors that have been marked "National Trust Historic Paint Color". They feature colors from various historic landmark buildings such as the Woodrow Wilson House, Homestead Resort in Virginia, President Lincolns Cottage. I've also used Olympic and really liked it too. Oh, and for the finish- I primarily use a Satin.
When it comes to spray paint I'm all about Krylon and Rustoleum. Rustoleum has some great "Painters Touch" colors. I love Straw-flower yellow. I've learned to use a gray spray primer when going from dark to light.