The quickest way to damage the Delrin screw is to use an undersized flat screwdriver, spend the money on the correct size. Sometimes the thread gets either damaged or caked with dirt, preventing the "cam tensioner" from screwing all the way down, effectively compressing the spring to give you the neccessary tension, clean out the threads with Break Cleaner, check to see if threads are still good, if they are damaged you will see it on the new Delrin Screw, the threading will be mashed. If the threads are slightly damaged you will have to find a Grade 8, 3/4 x 6" bolt with the same thread and screw it in to "renew" the thread, use lots of lubricant. If the threads are badly damaged you will have to "re-tap" new thread.......
check this out:-
http://www.youtube.com/watch?v=zUUA7l6fzIk
HTH
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TurboHobo
H14T
H16
P18
G-Cat 5.0
P16
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