to learn about needles & thread visit the Superior Threads website- they offer a vast amount of free information to teach you all about different threads, needles- sizes, weights, uses...they have free charts you can print off that tell you about each different thread- what it is best used for, the weights it comes in and what needles to use with it. a great resource to have- they also have classes & clubs. you should clean your bobbin area with every bobbin change- as for should you use a ('shiny polyester'?) - if you want to-- people quilt with all kinds of different threads- for all kinds of reasons- cotton, polyester, silk, invisible, metallic; some like very fine threads, some like heavier threads- as long as the thread is strong (doesn't break constantly while you are trying to quilt with it) and gives you the look you are wanting it is ok to use it- some machines prefer one thread over another (machines sometimes seem to have minds of their own) visit the superior threads website- and experiment, do practice pieces trying different threads, needles- be adventurous.
