Choosing a throwing knife
Length:
Shorter, lighter throwing knives are generally harder to throw. They turn more quickly and it's a little more difficult figuring out your distance from the target based on how they land.
Knives between 12.5" to 14" are a good length. They are easier to throw, more predictable and stick well.
Weight:
You don't want a blade that is too heavy. A general rule is 1 ounce for every inch but you may want to go slightly lighter than that. An easier way to look at it is get something long enough and then look at the thickness. 3 - 4mm thickness should give you a decent weight.
A really heavy blade will tire you out and spoil your form and accuracy. If you can, test them out and pick one that you feel you could throw for a good while.
Steel:
A good quality steel will withstand more abuse but initially it doesn't really matter what it's made of. A better quality blade will be resistant to bending but if you are faced with a bent blade you can always pop it over 2 pencils and stand on the middle to straighten it out again.
Stainless steel will be a easier to maintain as rust on regular steel needs to be monitored.
Number of knives:
You'll want at least 3 knives. Throwing just one knife will mean you are walking to and from the target and you won't get into the "groove". If you have more than one knife you can try adjusting your next throw and gradually figure out what works. This is a big help in the beginning as you can move a bit forward or a bit back based on the first throw and start getting a feel for the distance needed.
FOR MORE INFO: - www. knifethrowing.info