School Hard-Tech Assignment.
About tennis balls!
Why not an automatic tennis ball launcher that launches a tennis ball with a set speed every few seconds for tennis practice.
Just found this pic after googling tennis ball machine:

You should try to make it have automated angle changes and topspin-backspin capability.
Why not an automatic tennis ball launcher that launches a tennis ball with a set speed every few seconds for tennis practice.
Just found this pic after googling tennis ball machine:

You should try to make it have automated angle changes and topspin-backspin capability.
- Carlman
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sarcastic?psycix wrote:About tennis balls!
Why not an automatic tennis ball launcher that launches a tennis ball with a set speed every few seconds for tennis practice.
You should try to make it have automated angle changes and topspin-backspin capability.
thats kinda what they do...

Aussie spudders unite!!
- MrCrowley
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I'm not sure if I could get my hands on 2.5" (65mm) pipe.
Edit: See comical post below.
You have some good ideas, I actually have a dog, so it may be easier to convince my teacher to build a cannon for launching nerf rockets, for my dog to retrieve, then my dad launching antenna's over our house, or under for that matter.dewey-1 wrote:MrC;
It would seem that the best choice in your situation may be some form of Nerf Rocket Launcher. I say this because:
1. The Nerf Pocket Football as an ammo does not appear to the average person as being dangerous.
2. A small portable pneumatic launcher of an overall length of 24" to 36" is also less intimidating. Brightly colored to look more like a toy.
As far practical uses for client/s, make a list and add to it as you think of more.
Home use: Clog remover.
Commercial use: Dog training: Locating and/or retrieving scent ladened football.
Industrial use: Tether line launcher. (Same as Antenna use)
Be sure to put Warning Labels such as: 25 to 50 psi max! The low pressure will also seem less dangerous. Obviously design it for higher pressure but only show it as having only a lower pressure capability.
Edit: See comical post below.
Last edited by MrCrowley on Thu Feb 07, 2008 1:41 pm, edited 1 time in total.
- jackssmirkingrevenge
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Sounds like some sort of futuristic biological weapon, poor dog!MrCrowley wrote:a cannon for launching nerve rockets
hectmarr wrote:You have to make many weapons, because this field is long and short life
- jackssmirkingrevenge
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"Dammit I can't seem to find my ammunition"
"What, you mean you've lost your nerve?" *chuckle*
"Idiot" *whack*

"What, you mean you've lost your nerve?" *chuckle*
"Idiot" *whack*
hectmarr wrote:You have to make many weapons, because this field is long and short life
- Brian the brain
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I thought the *breaking up ice* idea was kinda good...
" and this is my pneumatic icebreaker"
** points out the 25 psi max warning**
" and now watch me break up ice.....bergs...."
***KABOOOOOMMM****
Mushroom cloud----fade out---
" and this is my pneumatic icebreaker"
** points out the 25 psi max warning**
" and now watch me break up ice.....bergs...."
***KABOOOOOMMM****
Mushroom cloud----fade out---
Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!
Can't ask for a better compliment!!
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!
Can't ask for a better compliment!!
Ok Mr Crowley, I got a client for you and it might just impress your teacher it is a company called Power Com from here in Tri Cities that one of my buddies is a foreman for. they do network installations in new construction and they need a new launcher that will launch a skinny rope or wire up and over conduit in the ceiling so that they can pull runs over the top of them. And since you live so far away all you would have to do for them is create the prototype and then send them the designs so that you can keep the prototype and will be able to give them any help by being able to look at yours if they have any trouble with theirs.
<a href="">DONT TAZE ME BRO.. DONT TAZE ME... AHHHH</a>Yea, that's definitely going to get you at least a tazer.
facebook.com/biggrib
dewey-1 is absolutely right about the psi and warning labels.....
I was thinking of a low speed soft ball tossing device for a handicap person so they can play ball, or mabe a confetti launcher for the local theater?
You said that you are doing this for a school project? I know that in WA we have a no weapons policy at our schools. You may want to talk to the school officials before building a "cannon" for a class project. [/quote]
I was thinking of a low speed soft ball tossing device for a handicap person so they can play ball, or mabe a confetti launcher for the local theater?
You said that you are doing this for a school project? I know that in WA we have a no weapons policy at our schools. You may want to talk to the school officials before building a "cannon" for a class project. [/quote]
Well, if you want to be a bit sneaky, print safety labels in pressure units that no-one has any idea about.
Torr might not be a good choice, because... well, HEAL operates at around 16700 torr. I know it's a high pressure cannon, but 16700 torr sounds a lot more than 300 psi.
Pascals is worse of course, because there are 132 to 1 torr. Kilopascals would be reasonable, but there are still more of those than there are psi. Steer clear of Megapascals, simply because Mega sounds like a lot.
What about "Use under 0.1 ksi"? - that's still 100 psi, but the decimal point makes it seem less.
*This post brought to you by Ragnarok's Mostly Useless Advice Ltd.*
Torr might not be a good choice, because... well, HEAL operates at around 16700 torr. I know it's a high pressure cannon, but 16700 torr sounds a lot more than 300 psi.
Pascals is worse of course, because there are 132 to 1 torr. Kilopascals would be reasonable, but there are still more of those than there are psi. Steer clear of Megapascals, simply because Mega sounds like a lot.
What about "Use under 0.1 ksi"? - that's still 100 psi, but the decimal point makes it seem less.
*This post brought to you by Ragnarok's Mostly Useless Advice Ltd.*
Does that thing kinda look like a big cat to you?
- MrCrowley
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Great news....
Talked to the teacher today, he is very intrigued and gave it the AOK.
He said I can do it for either the Dog-Fetch idea, of making dogs fetch mini nerfs, or the antenna idea, and the antenna will be hooked onto a nerf.
He wasn't sure of my expertise, but after a few minutes of talking about past projects he said I knew enough for this build to be safe at school, I offered to show him via SpudFiles what I had made, but he said I didn't need too.
I'm more leaning torward the antenna idea, because getting a client would be far easier, and with the dog idea, the NCEA markers at the end of the year may get suspicious and think I made the client up, which gives me a fail.
He asked how I would keep it safe, I said I wouldn't test it at school, but he said it was required for me to pass. So I said i'll stick to under 50psi for testing purposes.
Since I now have my Restricted drivers licence I said i'll drive to school with the project and sneak it in as he said 'The School' may not see fit for me to build such a project in class.
@BigGrib
Thanks I just may take up the offer, obviously I would do it all via email.
I'll just check with my teacher to make sure an email is enough evidence and the markers don't think I made it all up.
How high is the conduit in the ceilings?
It'd be impractical for me to build a a launcher made out of 2" fittings to only launch a nerf 10' of the ground and over conduit.
Something between 15-20' is probably good enough.
Rag, I was thinking of just using Mpa, not necesarrily saying MegaPascles.
Or I could use BAR, 3.5BAR doesn't sound like much.
Thanks so far guys.
Talked to the teacher today, he is very intrigued and gave it the AOK.
He said I can do it for either the Dog-Fetch idea, of making dogs fetch mini nerfs, or the antenna idea, and the antenna will be hooked onto a nerf.
He wasn't sure of my expertise, but after a few minutes of talking about past projects he said I knew enough for this build to be safe at school, I offered to show him via SpudFiles what I had made, but he said I didn't need too.
I'm more leaning torward the antenna idea, because getting a client would be far easier, and with the dog idea, the NCEA markers at the end of the year may get suspicious and think I made the client up, which gives me a fail.
He asked how I would keep it safe, I said I wouldn't test it at school, but he said it was required for me to pass. So I said i'll stick to under 50psi for testing purposes.
Since I now have my Restricted drivers licence I said i'll drive to school with the project and sneak it in as he said 'The School' may not see fit for me to build such a project in class.
@BigGrib
Thanks I just may take up the offer, obviously I would do it all via email.
I'll just check with my teacher to make sure an email is enough evidence and the markers don't think I made it all up.
How high is the conduit in the ceilings?
It'd be impractical for me to build a a launcher made out of 2" fittings to only launch a nerf 10' of the ground and over conduit.
Something between 15-20' is probably good enough.
Rag, I was thinking of just using Mpa, not necesarrily saying MegaPascles.
Or I could use BAR, 3.5BAR doesn't sound like much.
Thanks so far guys.
- jackssmirkingrevenge
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Good stuff, the Dog-Fetch launcher need be nothing more than a simple straightforward pneumatic so you're sorted.
I would advise against drawing official attention to your online activities, you never know.I offered to show him via SpudFiles what I had made, but he said he didn't need too.
hectmarr wrote:You have to make many weapons, because this field is long and short life
- MrCrowley
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I'm actually building a cannon i've had planned for awhile, Sgort87 is shipping me some fittings and this hard tech assignment, coincides nicely with my design.jackssmirkingrevenge wrote:Good stuff, the Dog-Fetch launcher need be nothing more than a simple straightforward pneumatic so you're sorted.
I'll build it how I planned, but i'll keep the pressure down.
And i'm still not sure on the Dog-Fetch idea, i'll have to wait till next week to sort everything out, afterall I have until like July, to build and design this thing.
I see where you are coming from, and don't worry I wouldn't of directly gone to spudfiles, I have some of my cannons bookmarked on my school account and he wouldn't care what the site is.jackssmirkingrevenge wrote:I would advise against drawing official attention to your online activities, you never know.I offered to show him via SpudFiles what I had made, but he said he didn't need too.
He's a cool teacher, he would get in more trouble then me if the police found out or something, so he defintely wont tell anyone inside the school apart from fellow Hard-Tech teachers.
I'll install a 120psi pop-off valve too, and never take it over 50psi at school, and dismantle it while it's stored at school and take the valve assembly home with me.
- jackssmirkingrevenge
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Here's a thought, with a big enough calibre, and small enough dog...MrCrowley wrote:And i'm still not sure on the Dog-Fetch idea
hectmarr wrote:You have to make many weapons, because this field is long and short life
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