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Posted: Sat May 19, 2012 12:51 pm
by POLAND_SPUD
ohh now you're an electronics expert

you even know what a capacitor is
they launched cameras from spudguns so I guess a pressure sensor can handle it
Posted: Sat May 19, 2012 1:28 pm
by jackssmirkingrevenge
I'm the first to admit that electronics is not my forte, but I do have a fairly good grasp of Newtonian physics, which is what we're talking about here
Even a simple sliding switch can be a problem. If mounted in line with the axis of motion of the projectile, the inertia of the slider itself can cause it to move either when it's being accelerated on launch or decelerated on impact.
they launched cameras from spudguns so I guess a pressure sensor can handle it
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From a low pressure ball valve cannon like the above, probably less than 200 fps perhaps - but we're talking about high subsonic velocities here, that's a lot more stress on the components.
Posted: Sat May 19, 2012 4:20 pm
by ramses
Yeah, switches do not do well under acceleration.
My high school lost a match at the NRL 15 lb championship because a spade connector ripped itself off our switch. Solder everything, and use a removable link or screw on/off switch. The switches are really expensive (>$60), though.
Posted: Sat May 19, 2012 5:10 pm
by jackssmirkingrevenge
tada, prototype N<sup>
o.</sup> 1
It works, but only at 5 or so metres, and because the epoxy is in contact with the base of the piezo buzzer it sounds quite faint. Still, it's a start

Posted: Sat May 19, 2012 5:56 pm
by sharpshooter11000
Looking good, are you going to use a sabot with it? Also, loving the hole in your table!

Posted: Sat May 19, 2012 11:37 pm
by jackssmirkingrevenge
sharpshooter11000 wrote:Looking good, are you going to use a sabot with it
The fins are the same calibre as the barrel, so all it needs is a pusher plate.
Also, loving the hole in your table!

Few things in my workspace
don't have projectile-related holes in them

Posted: Sun May 20, 2012 2:20 am
by Petitlu
Remains is to paint it!
Good job, and as you say it is the beginning!
It is still 96g, the epoxy is heavy!
Posted: Sun May 20, 2012 8:49 am
by dewey-1
JSR;
Where is the COG location?
Can you send me the sat file to analyze?
Here is an interesting possibility.
http://www.jbgizmo.com/page22.html
Posted: Sun May 20, 2012 12:25 pm
by jackssmirkingrevenge
Interesting indeed!
dewey-1 wrote:Where is the COG location?
See attached
Can you send me the sat file to analyze?
I would have to redraw it to be relevant to the actual projectile.
Posted: Sun May 20, 2012 12:28 pm
by Petitlu
ignition of the NeverLost:
70 arcs with one AAA battery!

Posted: Sun May 20, 2012 12:39 pm
by jackssmirkingrevenge
Excellent

I just need to paint the projectile and make the pusher plate so this will be on its way to you in a couple of days.
Posted: Sun May 20, 2012 12:41 pm
by Petitlu
cool!
you sent me along with the other?
Posted: Sun May 20, 2012 12:51 pm
by jackssmirkingrevenge
Petitlu wrote:you sent me along with the other?
I was thinking of sending them separately... I don't know, I have a feeling that a projectile shaped object with electronics is going to raise an eyebrow at customs...
By the way, are you sure the firing area will be completely clear? I would not want to be hit by this thing :-/
Posted: Sun May 20, 2012 12:57 pm
by Petitlu
You can send them to me separately, no worries!
For the shooting area, there is no problem!

Posted: Sun May 20, 2012 2:45 pm
by POLAND_SPUD
I have a feeling that a projectile shaped object with electronics is going to raise an eyebrow at customs
not if you label it as
female pleasure device 