I need a project. And it needs to occupy a significant...

Kurt_ · Post by **Kurt_** » Mon Mar 03, 2008 4:53 pm

I'm thinking build a paintball gun.

ZN13 · Post by **ZN13** » Mon Mar 03, 2008 4:58 pm

You should build a Master Chief armor suit!

khaag · Post by **khaag** » Mon Mar 03, 2008 6:45 pm

timmeh87 wrote:
Kurt_ wrote: I'm not near a lake
*facepalm* how close do things have to be to be considered "near". we are less than a lakewidth from one of the biggest lakes in North America.

But yeah. heres some.

- finish my guitar
- refurb the northwood computer. new OS, repartition, upgrade? Go on tigerdirect.ca and make us a better computer for under $400, using what you have. The parents have offered to pay a couple times, its time to take them up on that.
- fix the guitar amp

This post gets me wondering... are timmeh87 and Kurt related? Dun Dun Dunnnnnn! What a twiist!

Turbo Tax 1.0 · Post by **Turbo Tax 1.0** » Mon Mar 03, 2008 7:00 pm

khaag wrote:
timmeh87 wrote:
Kurt_ wrote: I'm not near a lake
*facepalm* how close do things have to be to be considered "near". we are less than a lakewidth from one of the biggest lakes in North America.

But yeah. heres some.

- finish my guitar
- refurb the northwood computer. new OS, repartition, upgrade? Go on tigerdirect.ca and make us a better computer for under $400, using what you have. The parents have offered to pay a couple times, its time to take them up on that.
- fix the guitar amp
This post gets me wondering... are timmeh87 and Kurt related? Dun Dun Dunnnnnn! What a twiist!

brothers

Kurt_ · Post by **Kurt_** » Mon Mar 03, 2008 7:30 pm

He was in the room next to me when posting that. Talk about an anti-social family.

theelk · Post by **theelk** » Mon Mar 03, 2008 7:47 pm

I agree with khaag. You should make a spud gun out of PVC pipe. My brother made one and I think I still have it.

khaag · Post by **khaag** » Mon Mar 03, 2008 10:52 pm

Haha wooooooow! This shatters my entire universe!

Electric Rain · Post by **Electric Rain** » Mon Mar 03, 2008 11:05 pm

timmeh87 and Kurt_ are brothers...?!

My mind is also blown! This is a totally unexpected twist! *stares for a bit*

Huh... well, anyway... *shakes it off*

METROID ARM CANNON WIIMOTE MOD!

Seriously. It's something that won't cost much, will take A LOT of time (getting the mold just right, detailing it, ect.), and will be FRIGGIN' AWESOME once it's built! Plus, if it comes out awesome, you might be able to make some more and sell them to us!

Now it's actually practical as well, since we actually know the control scheme (this, in contrast to the thread a Wiimote canon a while back, before Corruption was released).

Kurt_ · Post by **Kurt_** » Mon Mar 03, 2008 11:06 pm

Spud gun, paint ball gun, what's the difference? (Barrel size only, if you're talking pneumatic potato gun).

And I have to say, if I ever made anything that held pressure out of pipe, I would go for pressure-rated ABS over pressure-rated PVC. Why? ABS tears over PVC splintering during a rupture. PVC does NOT show up on x-rays, either. Something to keep in mind when building things with high explosive potential.

I found a design I really like (http://www.gizmology.net/pbm.htm), and with a timer IC, I can make it fully-automatic (I think that's the word. You hold down the trigger and it keeps firing rounds until you stop holding down the trigger or it jams). The problem: I'm not sure what kind of valve I need for the job.

Here's what I have to work with so far: (As far as valve searching goes)

- One side of the valve will be all the pressure (CO2 tank). An always open valve will release all of the pressure.

- The valve must open and close when I tell it to (I think "Solenoid Valves" are what I'm after. Please help!)

- It must withstand at least 150 PSI. (Right now this is arbitrary, so let's keep this as our minimum value).

- It must withstand the proper amount of air flow. A 1/4" valve should be sufficient. An 1/8" one may be too small.

- A one-way valve would be preferred, but I THINK a two-way valve would be just as fine (One side has all the pressure, so it'd work, right?)

What is the name of the valve I'm looking for and where do I find one for <$20?

Electric Rain · Post by **Electric Rain** » Mon Mar 03, 2008 11:10 pm

You're right. It's a solenoid valve.

You'll be lucky to find a solenoid valve that can take that kind of pressure for under $50, let alone $20. Here's a start. It's a good price at $58, has a 1/4" pipe size and a 12VDC coil, but its max pressure for air is only 150PSI. The higher this goes, the more expensive the valve gets; quickly.

Post by **Triton** » Mon Mar 03, 2008 11:28 pm

build a fully automatic BBgun out of peices of pipe a bb gun barrel and whatever else you have laying around, i should finish mine someday lol

Kurt_ · Post by **Kurt_** » Mon Mar 03, 2008 11:48 pm

the pushbutton switch is connected to a modified kodak disposable camera. This provides the 200 volts required to open the valve because im using 10 times the pressure its designed for.

Random, I know, but a good tidbit I found on instructables, reminding folks at home that these are the opinions of 12 year olds, not professionals who know what they're doing.

As for valves, the guy in the site I linked to found 6 for $18 shipped on eBay. A local store may have what I need for $30, If I can get 12 volts and 1.5 amps. I'll have to go Ni-MH, right? (Maybe I'll make an air compressor that runs of 12 V to jam on the back too!

)

Another look at eBay and I think I found what I need:

24V valve, the stores sells 12V too

I find with the 24 volt models, they use significantly lower amperage. I'll have to see, but a Timer IC Stepped up might be enough to power one nicely.

http://stores.ebay.ca/valves4projects

Will those do at all?

Electric Rain · Post by **Electric Rain** » Tue Mar 04, 2008 8:04 am

Wow... why did I not think to check eBay, of all places.

Yeah, those look like they'll work fine... Just make sure you get one that's got a high enough air PSI rating. The one you linked to is 145PSI; would that be enough?

NiMH's should do nicely. Li-Ions are too sensitive for that kind of environment, and it's not like this thing needs to fit in your pocket.

Lead Acid is too big and heavy, and Alkalines... well... come on now.

You will be able to drive any solenoid you find with a 555 timer as long as you use a relay as well. You can use a MOSFET if you wanna get fancy, but that's not really necessary. If you want to keep it solid state, just use a solid state relay. They're more expensive, but it won't be too bad as you won't need a very large one.

I can help you with the circuit design (timer section), if you want. Before I was a part of these forums, I was a part of Electro-Tech-Online; a huge electronics forum. Now, given, I was a n00b there as well

, but I did pick up on a healthy amount of hardware design skill.

Kurt_ · Post by **Kurt_** » Tue Mar 04, 2008 12:52 pm

I'm about to start on the circuit design now, then a parts list for the whole contraption and how much it'll cost, before I go out on a giant adventure to make something that will cost waaaayyy too much for me.

If I need any help I'll let you know. I was hoping to get a burst-fire mode on this thing, but that really all depends on how fast the thing can fire, from there it's a matter of a fancy timer or two. Right?

Also, as this is more of a tech Q&A thread now, if anyone feels like doing something, they can move it if they want. It doesn't really matter to me.

Electric Rain · Post by **Electric Rain** » Tue Mar 04, 2008 2:23 pm

How many shots per burst? Three, I assume? I would just daisy-chain three 555 timers together in monostable mode. Nothing too fancy.

For fully automatic, just use a 555 in astable mode. Hmm... I really want to draw up a circuit for you now...