by Hermit on Fri Jan 23, 2015 6:42 pm
Jaeger my friend,I hate to have to tell you this,but by changing the shape of your cams,you have changed them from cams to pulleys,with all the advantages of pulleys,but none of cams.I have learned much during the time I have been a member of this forum,for instance,that in order to obtain maximum power,you need the longest draw you can get,and the fastest arrow (bolt) speed,and for a bonus,string acceleration if you can get it!
There are 2 types of cam,constant motion and accelerated motion.the function of these 2 types of cam is well described by their designation.The cams used on Patandjali's bow(the bow we all fell in love with,and the inspiration for the interest in this type of crossbow)are accelerated motion cams.Their ovoid shape and off centre pivot shows this.By making them concentric,you have lost their ability to provide string acceleration,which is going to reduce arrow speed and power.Please don't take this as a criticism,it is not intended to be one,simply a reminder to anyone reading your posts and intending to build an R.D.T. crossbow,that while building these cams is made simpler by changing their shape to concentric they are going to lose the advantages that a cam has over a pulley.
Hermit.