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Registered Member #1608
Joined: Sun Jul 27 2008, 12:20PM
Location:
Posts: 10
May be, but they won't be for me ( Euro is worth more than the dollar, remember ). And since I earn around 360 euro's in 2 weeks with my new vacation yob, well, you do the math.
I also had a thought on optical triggering for the gun, so... I'm still trying to figure out wether I'll do SCR or optical triggering.
Registered Member #1608
Joined: Sun Jul 27 2008, 12:20PM
Location:
Posts: 10
Allright, I need to recheck my grammar: I actually meant the cut-off switches with triggering, sorry for that . Also found photodiode system, looks more promising than infra-red.
Registered Member #90
Joined: Thu Feb 09 2006, 02:44PM
Location: Seattle, Washington
Posts: 301
R.G wrote ... BTW, caliber is 9mm x length of the coil = about 5 cm
Good size; for your power levels the heavier and longer projectiles will work better. They carry more punch (kinetic energy) while making the timing requirements a little more reasonable.
For example, the pulse width for a 5cm projectile moving through a 5cm long coil at say 100 m/s is on the order of: t = dist/speed = (0.05m)/(100 m/s) = 0.5 msec
Any idea how much those Epcos capacitors weigh? I looked for weight specs but didn't even find a shipping weight calculator that would help.
R.G wrote ... I actually meant the cut-off switches with triggering ...
Cut-off switches? Tell us more - are you looking at v-switch designs now? That is a very good idea which is very effective at killing the dreaded suck-back effect, although it raises the circuit complexity considerably.
Barry Never use a long word where a diminutive one will suffice.
Registered Member #1608
Joined: Sun Jul 27 2008, 12:20PM
Location:
Posts: 10
Not really V-switches, I really ment photo optical gates in front of the coils. But I can't seem to grasp one aspect: when you use opamps and a mosfet for switching with the photo optical gate, does the mosfet endures the same electrical current as the coil, or the smaller charge a few volts above the minimum conducting voltage of the mosfet?
Registered Member #1633
Joined: Tue Aug 12 2008, 04:21AM
Location:
Posts: 45
If you are thinking about mosfet switching for that kind of power, forget about it. The mosfet will experience the same current that the coil experiences, and will be at the front of all the voltage fluxuations that the coil will produce. A mosfet that can handle 1KJ per stage would have to be very large, and very expensive.
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Best coil and fastest switching system for 8kJ
). And since I earn around 360 euro's in 2 weeks with my new vacation yob, well, you do the math.
.