A thumber is a general category that refers to many different kinds of throws, all based off of the pivot finger being a the thumb. However, this section will only talk about one type of thumber.
The thumber I will discuss is gripped in the following way: Place your thumb on the inside of he rim of the disc so that the frisbee is resting on the inside of your forearm Put the rest of your fingers on top of the frisbee. I would almost describe it as a backwards backhand. This throw is almost all wrist motion. Good luck making it go very far, I haven’t been able to accomplish much with this throw.
The hammer is a fun throw that is not completely necessary but can be used pretty effectively in competitive games of ultimate. This is another throw to impress your friends with when you are just throwing around.
To throw a hammer, put your fingers in the power position used for a forehand. Then, position the frisbee upside down and at a 45 degree angle above your head. Pull your arm back and throw. During its flight, the frisbee should gradually level out. By the time it reaches your target’s hands, it should be completely level and upside down.
The Basic Forehand grip is in principle very similar to the corresponding backhand grip. The middle finger of the throwing hand is inside the rim and the index finger is extended towards the centre of the disc for support. The advantage of this method is control. The disadvantage is a corresponding loss of power, because the spreading of the fingers makes it impossible to cock the wrist back as far just before release.
The Power grip of the forehand has the index finger next to the middle finger and hard up against the rim. This grip increases power since the wrist can now be cocked back further and more snap imparted no the disc. As expected, there is a loss of control as there is no finger to support the disc. The disc has a tendency to wobble up and down, and this can reduce distance if the disc and the wrist are not at the same angle at release.
There are 2 main back hand grips: the Basic grip and the Power Grip.
The Basic Grip gives a high degree of control, since the index finger along the rim helps with direction and the middle finger supporting the disc supplies stability. On the down side, there are only two fingers gripping the rim, and this leads to much less power than most of the other grips. Most of the power in a grip comes from the ripping of the disc off the end of the index finger.
The Power grip is when all fingers are gripping the rim tightly, and there are no fingers supporting the disc. This means there is a considerable loss of control, since the release point is much harder to judge. A fair degree of control can be regained through practice, and the loss is offset in some ways by the large power gain produced by the disc ripping off the end of the index finger. This grip does however make it harder to throw the high backhand as there is no support for the sharp upward push on the disc just prior to release. In general, the tighter the grip, the more spin which is able to be imparted to the disc, making the frisbee unaffected by wind.