driver

I have just recently bought a 405nm PHR-803T Blu Ray Laser Diode and am going to be using this circuit to drive it: http://laserpointerforums.com/f42/diy-homemade-laser-diode-driver-26339.html
My first question is will 4 aaa batteries be enough to drive it?
and my second question is does anyone know what resistor I could replace the potentiometer with to make it a constant 100-120 mA? no one around here sells the 100ohm pot i need, i don't want to order it and I don't really want it to be adjustable anyway...
thanx for any help..

oh and would the 120 mA be to much? i want it to be a burning laser but i dont want to destroy the diode...

to get 100mA output on a LM317 setup you would use a 12.5ohm 1/8W resistor, and for 120mA output you would use a 10.4ohm 1/8W resistor. these are the exact values for the desired output. you would need to find the closest available value of the resistor you need to use. for example, if you wanted 100mA and all you could find is a 10ohm 1/4W resistor, then use it. hope this answered your question

thnx for the reply but i got tired of waiting for a reply (im very impatient) and went out and just bought me a DMM so i could just figure it out so i am kinda glad for the wait cuz now i have a multimeter.