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Unread 22-03-2013, 09:27
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Re: Curved shooter mysterious hook.

Quote:
Originally Posted by lemiant View Post
Our shooter includes a 90 degree curve and a top to increase compression. We're shooting with a white high-traction wheel from the kit.
The problem is that when the frisbee exits the shooter the side nearest the wheel ends up higher than the side opposite the wheel. Making it hook. Has anyone experienced a similar problem?
Yes. This problem seems to be inherent to any non-pneumatic wheeled shooter. Your compression numbers (1/2") sound right on. We ran 10.5" from the wall to the wheel tip (so 1/2") the entire season on Banebots wheels. Maybe you need a touch less for a different wheel, but that's what we use.

What you have to do now is constrain the frisbee. Physically prevent it from "popping" and then it won't anymore. The simple addition of some slippery plastic guides might be all you need.



Here's a picture of the ones we made for the WPI Regional. The simple addition of these guides removed the problem entirely, resulting in a very straight shot with dramatically more consistency. When we used to miss 1-2 frisbees per cycle, we now miss 1-2 frisbees per match, and that's probably user error.

The more you stop the frisbee from moving around, the better your accuracy will be.
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