Need Advice! - Shooter is not performing as expected

[AndrewSears]

We were thinking the same thing. We found a spring chain tensioner last night and are going to try that after adding 2 links to the chain. We have a floating pin (1/2" bolt) in the take-up that allows slight motion and everything is captured with flanged bearings. We have double nut on the end of the bolt so we would not put a thrust load on the bearings. This sprocket is running entirely on the bearing inner race....

Now that I think of it, I wonder if this being allowed to float slightly in the bearings could be the problem.. ?? Since everything is sandwiched between flanged bearings, maybe we need to tighten this up a little so we lock everything to the inner race of the bearing.

[Kevin Sevcik]

I think you're probably spinning your wheel too fast, at the least. If you ever managed to hit your 24000 RPM, the tangential velocity on your wheel would be 571 mph. With an expected maximum frisbee velocity of 285 mph.

You're never going to get a frisbee going that fast. So your wheel will always be slipping and you'll always be applying sliding friction to the frisbee. Sliding friction is only dependent on the compression force, not the speed of the wheel, so spinning your wheel faster isn't gaining you anything.

So back to the actual problem. You haven't mentioned whether this is a linear shooter or a 90 degree wrap shooter. Also, what's the distance between your wall and the rim of your wheel? I think most people are finding something around 10 1/2" to be a good distance there.

If you're running a 10 1/2" compression, then your frisbee is going to bow up a good bit in the middle. I think it'd end up squashed between your two sheets of UHMW if you only have a 3/16" gap. That'd add drag and lower your shooting distances as well.

[Justin Shelley]

Use a pneumatic tire

[Willyspu]

Make sure there is sufficient friction between your wheels, the surface the Frisbee rotates against and the Frisbee.

Hard wheels may not produce the friction needed to spin the Frisbee, we riveted our hard wheels with a traction material and that helped a lot (that's why the pneumatic wheels work well).

The Frisbee needs both force and spin to fly properly.

Jim Russell
Mentor 2144

[budzilla]

There may be other factors at work with your setup such as frictional losses (we had those as well), but we have experienced less distance with more speed based on a none contact tachometer. I think that it is just like a funny car breaking the tires loose on launch. There's a point where adding more power is just making smoke and slowing the launch, be it car or Frisbee. We were peeling rubber off the tire. The pneumatic tire offers a MUCH larger contact patch on the Frisbee because of the compliance and therefore helped us a lot. BTW, 6440 rpm on the pneumatic was too much, but now we can PID the shooter, YAY!

Best of luck to you!