Capacitors will store voltage. When the capacitor is full of voltage
it lets out a burst of stored voltage, and then begins to store
it again. It does this by the use of filaments. It is not that important
to know how they work, but it is important to notice the af-
fect they will have on your machine. I have seen some texts and
heard some artists say that the capacitor is only there to relieve
the amount of spark that you see on the contact area of the machine.
This is simply not true. The capacitor can actually change
the speed that the machine runs! A really good trick to figure out
the best cap for your machine setup is to have interchangeable
caps with clips on them. You can have your machine all setup
and running, and have it so that you can quickly remove the
cap and swap it without having to tear the whole machine down.