Shooting issues

[akash992391]

Other pic is here

[akash992391]

Yeah we did try

[stryker0603]

Are the discs hitting the bolts you have holding the shooter down? Any idea on what your compression is?

[akash992391]

I don't think is hitting the bolts and idk about that......

[akash992391]

Can u give us an idea how u connect those directly to motor bec we try didn't work so we have to use gears.....

[TheMadCADer]

I would highly recommend mounting it so that those bolts aren't there right at the exit. There's almost no way that isn't causing a problem. Try bolting through the side walls above the area discs travel through, or the top surface.

Another issue could be that your wheels aren't lining up well with the flat edge of the disc, so they aren't getting a good contact. If you can get the center of the wheel tread to touch the disc on the flat edge, you should get good results.

Also, I'm assuming you've fiddled with compression and motor speed, but if you haven't, that's step 1.

[shadowjm]

Most of the linear shooters that people are using are using an overdrive setup for their gears. It appears from your picture that you have a small gear on the motor and larger gear on the wheel which will reduce the motor output rpm. Maybe try putting a larger gear on the motor?

Regards,

John
37777
Mechanical Mentor

[shadowjm]

Also you may need something with some grip to it on the opposite wall from the wheels. This will allow the frisbee to spin more. More spin = more stable flight

John
3777
Mechanical Mentor

[shadowjm]

http://www.andymark.com/product-p/am-0320.htm

[akash992391]

Ok and other thing do we have to,have tight enough both side to throw higher frisbee.

[Jorge Ayala]

Our team is getting some awesome shooting distance with just one motor, our shooter design in some way looks like yours. We had some issues regarding the shooting distances so we decided to use the CIM motor without any gears. And we also lifted the tire a little so that contact with the frisbee is made from under the tire (if you want to do this make sure it makes a decent compression). Another way to improve accuracy and shooting distance is eliminating vibration, we are still trying to figure out how to do that, we have already eliminate it to some extent and it has resulted in more accuracy, but we still have some vibration to get rid of.

This is a small (very small) video of our shooter.

Hope the advice helps you.

[dchartley]

If you find the direct drive parts or out of stock at AndyMark, I bought a couple of extra ones and can FedEx them to you. Let me know. Email at dchartley@seattleschools.org.

The sheet metal you are using looks like it may flex a lot. Might try to stiffen up the lower contact surface to that it does not flex while shooting.

Doug

[andrewthecow]

Just to sum up the other advice from this thread and give a little more input, I'd say there are 5 main ways to improve the shooting:
1. Check your compression of the frisbee; too much or too little can vastly diminish the amount of momentum transferred to the disk from the CIMs.
2. Direct drive the wheels using the AndyMark 8mm hub or at least get the gearing near 1:1.
3. Make the surface inside the shooter and opposite the CIMs much rougher, so that energy is more efficiently transferred into making the disk shoot further. My team is using skateboard grip tape for this.
4. Make sure that bolt heads do NOT contact the disks as they exit the shooter.
5. Watch the CIMs as the disks shoot and make sure that the c-channel they're attached to isn't twisting. If it is, it's changing the amount of compression you're getting.

Good luck at competition!

[GilaMonsterAlex]

First thing I would do is speed up the wheels. You need to find a way to make it so. Then I would check the compression, and contact.

[bbuncher12]

In addition to the advice given by the people above, once you get it working well, consider making the second wheel (closest to the end of the shooter) move slightly faster than the first wheel, either with gear ratios or programming. This should allow the frisbee to start spinning and moving from the first wheel, then launch out with a great deal of speed at the second. This greatly helped our shooter both with shooting distance and vibration.