Electrical: 9 volt to 12 Volt DC conversion??

hey, everybody. I'm currently working on a prop project for a film buddy of mine and I've come across an electrical problem. I'm great with mechanical issues, but once it becomes a question of volts and amps, I'd rather have a few educated/experienced answers.

I'm building a squib cannon. Basically, you pressurize a tank up to about 10-20 psi, attach a ball valve, hook a "bloodline" to it full of movie blood, hide the end of the hose under the actors costume, and on cue release the pressure, causing a very messy (and hopefully impressive) explosion of movie gore. Safer and cheaper than explosive squibs, I've used other people's rigs about a dozen times on set.


Usually, its a PCV pipe with a ball valve and garden hose. I figured I could make a better one. Electrically triggered with a solenoid valve and a sturdier construction.

However, after I started looking around, I couldn't find any 9V solenoids that can withstand 100 psi. Most of the solenoids I've found are in the 12 or 24V DC.

I was wondering if I could use multiple 9V batteries in series to generate enough electrical power to activate one of these solenoids. Would that work? or would it be an epic failure? I need the solenoid to fire rapidly and efficiently, on cue with the hit of a trigger. Timing is very important. Also, if it worked, would my batteries be dead in a few shots or would I at least get a couple dozen blasts before I had to change them?

If anybody out there has any electrical experience that could help, I'd appreciate it.

I would say to stay away from 9v batteries. They are nice in that they have the volts and a small size, but they just don't have the mah to support long term use. If you connect them in series (+ to -) you will have double the volts (18v) but the same capacity (ah). If you connect them in parallel (+ to + and - to -) you have the same volts (9v) but double the capacity (ah). I would say to look at buying a battery pack in the voltage you need. You should be able to find one in the exact voltage you need and usually with a much higher capacity. I guess if you really want 9v batteries you could always use lithium ion 9vs. They still won't have a great capacity, but it is better.

Here is where i get most of my battery packs from.

http://www.batteryspace.com/

Thanks a ton for the advice and the link!

http://www.yuasabatteries.com/ sells batteries (thru dealers) that will support what you need. they make a nice 12v battery that is the size of a pack of cigarettes. i purchase my stuff thru ADI (an alarm part distributor) they have tons of stuff that can be used, relays,batts,wire etc. a catalog can be downloaded from their website easy enough.

Thanks, ClearCaseMan! There is a dealer about 30 miles from my home, I might swing b there and see if they can get in what I need.