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DELETED (Inactive)
5 Posts |
 Posted - Jun 13 2001 : 11:10:07 PM
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This is about my ignition system but I know more people might look here if you want to transfer it fine. Any way I have a cap - ignition coil type setup for my sparker. It uses the same disp camera pcb for charging the cap as here http://homepages.paradise.net.nz/mikeab/spudgunsnz/index.html but it is HEAVILY modified.
I have added a lead to the on pcb momentary switch that starts the charging process, added leads and cut the holder for the single AA bat setup. These leads go to a 9v plug There is an on-off switch wired to the + lead. Then I have a 2xAA holder plugged into it. I have added leads to the led and cap to mount them off board. I also added a push type connector to the cap. The mom. switch, on-off switch, led, and push connector (like a stereo speakers) are all mounted on a top plate that goes to a junction box. From there the + goes to another momentary switch then to the + on the ignition coil, and the - goes to the coil and to screw #1. The coil out goes to screw #2 which between the two lies a little over 1" gap. It has a nice white spark but I havent shot my new gun yet as I have been shocked twice by the 350v 160uf cap (about 1.5 times as strong as a 120v wall outlet shock) and just a few hours ago got lucky enought to get a jolt fromt one arrm through the chest to the other out of the coil (felt like a mac truck) So I am siliconing, liquid elec tape, and epoxying anything that will juice me again.
Ok here is the question, I am currently running 3v And I know the 9v charges up and the cap disapates, I have the box apart and not going through the coil though. What are the advantages, faster charge time and more juice = bigger spark of course, and disadvantages to the 9v rig on the pcb and circutry. Thanks in advance.
Also like to say nice page with lots of usefull information That I used towards my first gun with 1.5:1 cham to barrel ratio w/ mod bbq sparker.
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DELETED (Inactive)
5 Posts |
Posted - Jun 13 2001 : 11:13:21 PM
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Sorry about the title it should have been electronics, Its late and the term electrics sounds rather illiterate.
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DELETED (Inactive)
5 Posts |
Posted - Jun 14 2001 : 12:03:13 AM
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I have a better question pertaining to my first problem. The 9v bat has three times the volts but less amps, the 2xAA has 1/3 the volts but more amps what would be better then?
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DELETED (Inactive)
5 Posts |
Posted - Jun 14 2001 : 12:23:25 AM
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You need an edit button. Ok I just realized that no matter what setup I use I will get the same spark in the end due to the cap limits.
So which setup will charge the cap fastest and be the safest on the pcb circutry.
Ok now I got two of these boards and I used the first as my tester. If I took the cap off of that and combined it with the other it would send 700v and 300uf to the coil right? Which WOULD cause a higher spark in the end (dont really need it but im just contemplating ideas) right? Also I would run this parallel to the first cap and not in series, correct. Hmmm I guess I should add more insulating to be safe HAHA
I built my first one with a 133ci chamber and shot it for a week then deamed it too weak. It would shoot co2 cart.s through 3/4" 5 ply plywood at 40ft with a 5' by 3/4" barrel. It was designed for a 1.5"x4' barrel and had a cham to air of 1.5:1. My new one has a 190 ci chamber and with the same barrel have a 2.1:1 ratio. This should be effectively 2 timees stronger onder ideal conditions seeing as how 1:1 is needed togo out the barrel and the first has .5 for thrust vs 1.1 in the new one. Also I want to ignite anything I throw in there and have it burn fast thats why Im doing this. My first gun was very picky on prop's and favored a car cleaner and propane. Thanks again
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Jun 19 2001 : 3:30:43 PM
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OK. Let's see if I can answer a few of these.
1. There is an EDIT button. Hold your mouse over the various icons at the top of your post. One of them is an EDIT.
2. Camera flash units are very dangerious. Very dangerous. You were already zapped, and you are lucky you were not killed. The capacitor will hold enough jouls of energy to easily kill an adult. Becasue of this, I do not recommend the use of any ignition circuits that use capacitors to store a high voltage.
3. Two capacitors will not increas the charge to 700V, but if paralleled will provide a higher current spark. Also, this will increase the danger significantly. Again, I do not recommend high voltage circuits that contain capacitors.
4. 9V vs. 3V. I would stick with the AA batteries, or use Cs or Ds if you don't want to recharge often. Increasing the voltage past about 4.5V will throw many components (mostly the transistors and capacitor) out of tolerance. This can result in burned out transistors, or exploding capacitors.
5. If you want a real high voltage circuit that safely produces a continuous spark, see http://www.aaroncake.net/circuits/hvgen.htm
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DELETED (Inactive)
5 Posts |
Posted - Jun 23 2001 : 10:28:35 PM
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Aaron:
Thanks for the reply. I figured out by running the caps in parrallel that it wouls just double the capacitance and not the voltage. I have a bank of three wired up (all 330v but two 120uf and one 160uf) but I never put it to use, and probably wont. I know they are dangerous but are alot more simple to make than the high voltage generator you use. Plus I have it in a so to say stock on the gun. I dont think it would be ergonimic to use your setup and the mass of D cell batteries.
Getting shocked by the cap was nothing to getting shocked by a coil and I am gratefull I didnt get hurt. I was thinking it should have done the reverse diphibulator effect and stopped my heart. I have made every precaution possible to make sure I dont get shocked again. I put the cap, 2xAA, and pcb in a project box with the swiches, cap contacts and led mounted on the top so I dont have to touch anything. I also sealed the plug going into the coil, the plug boot was siliconed as well as the screw heads on the outside of the chamber, I even siliconed the wires into the push terminal that goes to the cap. Once again thanks again. Oh and I finally got it working reliable and am running 2 sets of screws running in series. I might add another cap so I can increase the gap between the screws , we'll see.
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Aaron Cake
Administrator
Canada
6718 Posts |
Posted - Jun 25 2001 : 11:24:13 AM
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It sounds like an interesting setup there, and I am glad you are taking safety precautions. Remember that those capacitors can stay charged up for months, if not years, so the circuit should never be considered safe.
Two spark gaps is something I have not thought of with a spudgun, and it shoulds like an excellant idea. It is a old Tesla Coil trick to use multiple spark gaps, thus reducing the load on each gap, and increasing the voltage required to jump them (ie. higher coil output).
The HV generator on my site is actually quite cheap to build, and will produce an arc much better than any camera flash. If you want REALLY high voltage, you can take the voltage multiplier out of an old TV and connect it to the output of the HV generator. Your final voltage will be around 100KV or so, but the current will be low and therefore the spark will be weak.
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Raising voltages on electrics
