Air Trajectory B/C

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Xystus
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Re: Air Trajectory B/C

Post by Xystus » February 22nd, 2015, 11:50 am

I got a package that comes with plastic and HDPE golf balls combined. the package reads "Practice Plastic/HDPE golf balls" . My only concern is that some opponent will argue that the word plastic is referring to the plastic balls and not the HDPE ones. But The rules clarifications do say that as long as the words "plastic", "practice" "golf", and "ball appear somewhere on the packaging its ok to use. which it does. Do you think my case would be strong enough to be able to use them at a tournament.

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Re: Air Trajectory B/C

Post by chalker » February 22nd, 2015, 1:20 pm

Xystus wrote:I got a package that comes with plastic and HDPE golf balls combined. the package reads "Practice Plastic/HDPE golf balls" . My only concern is that some opponent will argue that the word plastic is referring to the plastic balls and not the HDPE ones. But The rules clarifications do say that as long as the words "plastic", "practice" "golf", and "ball appear somewhere on the packaging its ok to use. which it does. Do you think my case would be strong enough to be able to use them at a tournament.
In situations like this, I always give the same advice: It's up to you to determine how far you want to push the boundaries of the rules. Why risk it? If there is a big tradeoff in performance, perhaps it might be worth it. Otherwise lots and lots of people have made successful devices with 'normal' hard plastic golf balls, so why not put a little more effort into your design and do likewise?

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Re: Air Trajectory B/C

Post by chalker » February 22nd, 2015, 1:21 pm

RyGonX wrote: Hmm, we found a golf that is labeled as 'practice' golf ball. On the back it says it's not made from polyurethane (foam) but from compression molded rubber. The texture feels like very hard foam (not spongy) and the ball CANNOT be dented when I tried to squeeze it. So would this count as a HARD special RUBBER (which is in the same family as plastics) PRACTICE GOLF ball? Its also regulation sized
Do the words 'plastic', 'practice' and 'golf ball' all appear on the packaging? If not, you risk a significant penalty for using them.

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Re: Air Trajectory B/C

Post by RyGonX » February 22nd, 2015, 3:14 pm

chalker wrote:
RyGonX wrote: Hmm, we found a golf that is labeled as 'practice' golf ball. On the back it says it's not made from polyurethane (foam) but from compression molded rubber. The texture feels like very hard foam (not spongy) and the ball CANNOT be dented when I tried to squeeze it. So would this count as a HARD special RUBBER (which is in the same family as plastics) PRACTICE GOLF ball? Its also regulation sized
Do the words 'plastic', 'practice' and 'golf ball' all appear on the packaging? If not, you risk a significant penalty for using them.
But couldn't an argument be made, since they are extremely hard like plastic? Therefore, not tampering with the original intent/challenge.

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Re: Air Trajectory B/C

Post by GoldenKnight1 » February 22nd, 2015, 4:05 pm

RyGonX wrote:
chalker wrote:
RyGonX wrote: Hmm, we found a golf that is labeled as 'practice' golf ball. On the back it says it's not made from polyurethane (foam) but from compression molded rubber. The texture feels like very hard foam (not spongy) and the ball CANNOT be dented when I tried to squeeze it. So would this count as a HARD special RUBBER (which is in the same family as plastics) PRACTICE GOLF ball? Its also regulation sized
Do the words 'plastic', 'practice' and 'golf ball' all appear on the packaging? If not, you risk a significant penalty for using them.
But couldn't an argument be made, since they are extremely hard like plastic? Therefore, not tampering with the original intent/challenge.
Sure. You could make the "argument" but as Chalker has pointed out you really need to weigh the risk vs reward. Imagine you use the ball you mention and the judge decides it does not meet the rules. They might not want to hear a thing about the "intent", so the two of you don't agree, you get your coach to file an appeal, and the appeal committee sides with the judge. Was it worth all of that? Even if the appeal committee side with you was it worth the entire process?

It certainly could turn out that you go to your regional and judge does not care but is that possibility worth the risk to your team?

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Re: Air Trajectory B/C

Post by jennyk » February 22nd, 2015, 5:13 pm

Alright already with the golf balls. Check out the links below for what can be used vs. what can't.

These are legal b/c they are plastic and have the word "plastic" on the packaging:
http://www.amazon.com/PrideSports-Pract ... 4MMYRDMRGG

These are not legal because they are foam:
http://www.amazon.com/PrideSports-Pract ... BEQ4ZC2X8T

And these are not legal b/c someone will eat them and leave you with nothing to launch ;)
http://www.amazon.com/Golf-Balls-Premiu ... 4MMYRDMRGG

Very easy to just order the correct ones, hopefully you'll have time to adjust your launch device to launch plastic golf balls. Just don't order the whiffle ball plastic type b/c it's hard to launch an object with air pressure if it's got holes :) .

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Re: Air Trajectory B/C

Post by ImNotSmart » February 22nd, 2015, 5:45 pm

bernard wrote:
ImNotSmart wrote:Again, thank you so much for having the patience to answer all of my dumb questions. I have a few air pumps at home but I'm not sure if they will be able to provide enough pressure. Is there any way to determine if an air pump would be able to move a ping pong ball 8 feet? Did the hose of the pump fit snugly into the brass fitting, or did you have to use anything else to make it fit? Also, how did you design the trigger for this device? Thanks again for your help! I greatly appreciate it!
The hose of my pump fit snugly into the brass fitting. If your hose doesn't fit snugly its probably because you have the wrong size of brass fitting (it would probably be pretty far off from the size you want since I don't think most stores sell brass fittings in small increments of sizes but the most common ones), your hose is damaged from removing it without loosening it (which could be fixed by adding some tape to the brass barb, but not too much), or your head isn't tightened (my bike pump hose's tightening switch is actually the opposite of most bike pumps in which orientation of the switch is locked/unlocked and it tok me a while to figure out.

Does your ball launch at all? If so, how far down the mass fall before the ball launches?

My trigger was made from just 2 eye hooks and a cotter pin with a long string attached. I had a wire attached nicely around my bike pump handle and the pin went through a loop in the handle. The two eye hooks held up the cotter pin. If you try this approach, make sure your wire attached to the bike pump handle will always be the same length to maintain consistent drop heights.
To be honest I just want to be sure I'll be able to get the device to work before I spend time gathering the materials. The bike pump I currently have does not seem like it will be capable of producing enough pressure to launch the ball far enough. Also, how did you change the distance your device launched the ball? Did you angle the barrel and if so how? Would it be possible to change the height at which the pump handle is dropped?

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Re: Air Trajectory B/C

Post by bernard » February 22nd, 2015, 10:11 pm

ImNotSmart wrote:
bernard wrote:
ImNotSmart wrote:Again, thank you so much for having the patience to answer all of my dumb questions. I have a few air pumps at home but I'm not sure if they will be able to provide enough pressure. Is there any way to determine if an air pump would be able to move a ping pong ball 8 feet? Did the hose of the pump fit snugly into the brass fitting, or did you have to use anything else to make it fit? Also, how did you design the trigger for this device? Thanks again for your help! I greatly appreciate it!
The hose of my pump fit snugly into the brass fitting. If your hose doesn't fit snugly its probably because you have the wrong size of brass fitting (it would probably be pretty far off from the size you want since I don't think most stores sell brass fittings in small increments of sizes but the most common ones), your hose is damaged from removing it without loosening it (which could be fixed by adding some tape to the brass barb, but not too much), or your head isn't tightened (my bike pump hose's tightening switch is actually the opposite of most bike pumps in which orientation of the switch is locked/unlocked and it tok me a while to figure out.

Does your ball launch at all? If so, how far down the mass fall before the ball launches?

My trigger was made from just 2 eye hooks and a cotter pin with a long string attached. I had a wire attached nicely around my bike pump handle and the pin went through a loop in the handle. The two eye hooks held up the cotter pin. If you try this approach, make sure your wire attached to the bike pump handle will always be the same length to maintain consistent drop heights.
To be honest I just want to be sure I'll be able to get the device to work before I spend time gathering the materials. The bike pump I currently have does not seem like it will be capable of producing enough pressure to launch the ball far enough. Also, how did you change the distance your device launched the ball? Did you angle the barrel and if so how? Would it be possible to change the height at which the pump handle is dropped?
How tall is your bike pump when it is fully extended? Mine is a little over 1 meter when fully extended but I have it at about 90cm tall when I launch because I have a mass on top. With a shorter bike pump, you'll want a shorter barrel (I hope this is intuitive, if not I can explain why). Do you feel any air leaking as the mass falls? If so, you'll want to add short strips of tape in the same way I explained before.
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Re: Air Trajectory B/C

Post by Argus » February 23rd, 2015, 7:53 pm

So the rules state that "making contact with the inside bottom surface is worth an additional 100 points." If the projectile hits the inside wall of the bucket and then the bottom do you still get the additional 100 points? So a total of 200 bonus points from that bucket shot. I know this is not the place for official responces and I am in the process of submitting a FAQ but the captcha doesn't work. Also that is almost exactly word for word what I am trying to submit. I just want to see how other people interpret it. Thanks.

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Re: Air Trajectory B/C

Post by dhdarren » February 23rd, 2015, 8:23 pm

Does anybody have a good alternative to a soda bottle for the air chamber? Is there a compressable bellows that somebody has bought? If so, could they please link me to where it can be purchased? Thanks! :D
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