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TeaBrid

Posted: Tue Jul 21, 2009 4:22 am
by inonickname
Nothing particularly special here- just a hybrid inside a 1/4" tee. It's just practice for the 200x mini- mainly in fueling. However, the 200 will most likely use regulated propane pumped directly into the chamber.

It was tricky to get a positive seal with the burst disk..but I managed. The schrader and spark gap were no issue. The barrel is just a length of aluminum tube, nothing that great.

Mixes will be 10x and above most likely.

I've tested it as a pneumatic and electrical tape (nitto) disks burst at 220-250 psi. Unfortunately, they don't blow out completely but I'm hoping that this will occur under combustion.

Not much else to say really... I need to get a new lighter (last one leaked) and a new syringe (retarded friend tried making a flamethrower with it, fuel stuffed the rubber.. Then I can attempt to get this tiny thing to fire..

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Used burst disks, fail @ 220-250 psi..

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Finger for scale

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Assembled TeaBrid

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Looking at the burst disk seat..this has an oring put on it, then the barrel with adhesive burst tape is added

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I decided that it would be good that I could keep it as a mini pneumatic if the fueling was too hard..But I'm not keen on the way the gauge needle flies around on bursting. I'll rebuild the mini repeater for this purpose..

Posted: Tue Jul 21, 2009 6:05 am
by jrrdw
That pretty cool. :D What are your burst disk made from?

Posted: Tue Jul 21, 2009 6:09 am
by inonickname
me.. wrote:I've tested it as a pneumatic and electrical tape (nitto) disks burst at 220-250 psi.
2 Layers ought to be enough for a remote 20x test. I wanted to use something else, seen as nitto disks are minutely leaky (though it's very slow, perhaps slower than the teflon tape I used in the thread). Though the leaking isn't serious, you can pump the gun up, walk away, come back in a few minutes and the mix wouldn't really be affected, so I'm not too worried. Their adhesiveness makes it easy. Stick a square on the barrel and trim around.

Posted: Tue Jul 21, 2009 8:32 am
by jrrdw
Ok, I didn't catch on untill you just pointed it out. Try 3 layers??? :twisted:

Posted: Tue Jul 21, 2009 9:50 am
by qwerty
Man, that looks like it could be extremely powerful. Nice gun 8)

does any one know the calculation for a 200X spike pressure (im guessing very high :twisted: )

Posted: Tue Jul 21, 2009 10:09 am
by jackssmirkingrevenge
I used ordinary stationery tape in my 6mm bust disk, one layer was good for 400 psi or so.

Posted: Tue Jul 21, 2009 4:39 pm
by theBOOM
Hm 3 questions ino... What did you use as a spark gap and how reliable is it.. does it ingite with ease? What are you using for ignition? Is it the electrical piezo igniter?? And lastly could you explain your burst disc setup a bit more detailed :P B.c I was thinking of a similar idea but im not sure if its the exact same thing or if you didnt something different...

Good job on it :P
btw what is the tee made out of?? what is it rated to?

boom :twisted:

Posted: Tue Jul 21, 2009 7:15 pm
by inonickname
I'll use a camera flash for higher mixes, and a piezo for low ones. The gap is just the wire held to a suitable distance then held in place with epoxy.

Burst disk setup is simple, a burst disk is just forced between an o-ring, the barrel and a small plate to suporrt the disk. It's a brass tee, rating I don't really care about.

Happy birthday by the way, get much?

Posted: Tue Jul 21, 2009 7:41 pm
by twizi
what are you usin for ammo did nt see it in the thread

Posted: Tue Jul 21, 2009 7:45 pm
by inonickname
twizi wrote:what are you usin for ammo did nt see it in the thread
Dunno, perhaps a lightweight dart or similar.

Posted: Tue Jul 21, 2009 7:53 pm
by twizi
whats the diameter of the barrel

Posted: Tue Jul 21, 2009 8:42 pm
by theBOOM
thanks ino and happy bday for you too
im getting 500 dollars for my bday,too bad ive been sick with an outer ear infection.... i hope it goes away soon so i can start spudding again... btw we should talk in the chat soon i have 2 ideas for simple burst disc setups for mini hybrids...jehehe ur lucky u got that lathe for your bday ..have somefun and build aweso0me cannons...again, happy bday