Firing old photo flash bulbs

I have a truckload of these old flash bulbs and we're doing a show that uses an old bellows camera with a flash. So I have to rig up something to make them fire each night for the show. How much juice do I need to fire them?

Capacitor discharge. Probably not much voltage needed if you get the right cap.

I wonder if a piezoelectric ignitor from a gas grill would have enough punch all by itself?

From what I understand, that works with gas-based strobes but not these. These look like a bulb stuffed with magnesium wool. You have to apply enough juice to actually burn the Mg. The googles is failing me.

Buy an old camera and take it apart?

I'm pretty sure that you can just stick a paper clip in there and fire them off.

Whoops, just looked at your photo again. I thought they were flash cubes.

That is a viable option. Some guys buy a disposable camera and hack the strobe through an AA battery. The problem is we'll have about 23kW of light flooding the stage and a wee little strobe won't be seen. Theaters use old flash bulbs for two reasons: They make a big flash of silver light, and they make the right pop sound which will be crucial for our production set in 1956-57.

I'm not against just making a flash for the sake of making a flash, but I'm a bit of a perfectionist. I have the correct bulbs so I'd like to make them fire. If I can't do it easily, then we'll talk about smaller strobes.

One site I checked showed a range of 3 to 30 volts. Given that steel wool will burn if you put it on the terminals of a 9-volt battery, these things shouldn't take much. I would just take a few dry cell batteries, run leads to the terminals of your lamp, and see what happens.

curtis73 wrote: The problem is we'll have about 23kW of light flooding the stage and a wee little strobe won't be seen. Theaters use old flash bulbs for two reasons: They make a big flash of silver light, and they make the right pop sound which will be crucial for our production set in 1956-57.

Get a studio strobe, hung from the rafters? Audience won't see where the ball of flash came from, but it will be a ball of flash, no less. Then you need the pop sound.

Maybe start with something like this: graflex flash

From their you could gut it and move the innards to you camera body.

One you get the guts out you can sell it to a Star Wars collector to build a light saber.

On edit: Additional info on the flashbulbs

Why fabricate something when there are tons of old flash guns like the one above that are essentially valueless now? Just use a flash gun designed for these bulbs.

Easiest and cheapest available "classic looking" bellows camera is a Polaroid 100/250/350 type, and most of those came bundled with a flash gun using those bulbs.

The camera I have as a prop actually has a fake flash on it that I made from PVC pipe and a shop-light shade. It doesn't have a socket or anything in it, but I can make that happen.

Here is what I have:

bastomatic wrote: Why fabricate something when there are tons of old flash guns like the one above that are essentially valueless now? Just use a flash gun designed for these bulbs. Easiest and cheapest available "classic looking" bellows camera is a Polaroid 100/250/350 type, and most of those came bundled with a flash gun using those bulbs.

Agreed. I actually have a few of those in the props loft. This prop needs to be a bit bigger and more authentic to what a newspaper reporter/photographer would have had in 1956.

Back in the day we used flashbulbs to fire black powder charges-- pretty sure a 9V battery will do the job-- and it's easy to try.

Just don't hold it in you hand when you do. Those things get hot!

Ok. I successfully got it to fire with a 9v. It took a second or two to light off, but it will work.

I think some epoxy to replace the gaff tape holding it together and I'm good to go.

curtis73 wrote: Ok. I successfully got it to fire with a 9v. It took a second or two to light off, but it will work. I think some epoxy to replace the gaff tape holding it together and I'm good to go.

I don't know how many bulbs you need to fire, but remember that while a 9-volt battery packs 9 whole volts into a compact package, it doesn't push much current, and will drain quickly in high-current-draw applications. Just something to keep in mind if you're using 9-volt batteries in your final iteration. That one ebay item showing a 3-cell flash handle looked like it used C- or D-cell batteries, which will last considerably longer.

maybe linked together?

In reply to fasted58:

Certainly multiplying the voltage should serve to fire them off faster.

Adding a capcitor should help it discharge faster.

Aaaand... we're changing our idea. The director was originally doing one flash per show, but has now added multiple flashes in a different scene. Although photoflash bulbs would be fantastic and authentic, I would need almost 200 of them to last the whole run of the show. I have about 30. I'm not buying 170 vintage flash bulbs and asking actors to change hot (potentially shattered) bulbs on stage.

So, back to the drawing board.

I will need a discharge flash that the actors can mime changing the bulb, but I also don't really feel like putting actors in close proximity to 300v discharge capacitors. And I need it in three days. Oh, and it can't make that whiny charging noise because it will be held up to a face near a wireless lavaliere mic.

Challenge accepted. Anyone have ideas?

Ring of white LEDs from HF flashlight around old flash housing? Might be tough to get it bright enough to see under stage lights

I'm experimenting with an SLR flash. I hacked it open and soldered extension wires from the capacitor to the strobe (and wires to a remote momentary switch on the tower) so I could hide the whiny box inside the camera body and mount the strobe in the cone.

Here's hoping the camera body muffles the charge sound. If not, maybe the sound tech can EQ a low-pass crossover at about 10khz and eliminate it.