Since then I have refined my techniques a little.
The diagram below is the basic setup
Basically it is a swinging arm, with a hammer attached, directed towards a unsuspecting light bulb. The camera is opened before the swing and at the opportune moment the flash fires taking the image.
When we left it last time I was having problems attaching the hammer, keeping the bulb still on impact and getting only one flash.
These problems have largely been solved. The hammer is now attached using a couple of metal strips with bolts through them. I added extra bracing behind the bulb to stop it going back on impact.
The multiple flash took a bit of working out. The problem was the hinge which formed 1 part of the switch did not move out the way enough when hit by the bolt, This caused the bolt to scrape against the hinge edge, so causing the multiple flash. This was solved by making the bolt hit the center of the hinge, and putting insulating tape on the edge.
I also put black cloth at the end of the garage so we have a cleaner backdrop.
The original intention was to fine tune the contact point by moving the bolt in and out. However it worked out easier to move the work bench.
Below is the setup in all it's glory. Note the pristine work conditions.
The way it works is that I hold the pendulum to one side, activate the camera in bulb mode using a remote trigger. Let go of the arm and hopefully once the flash has gone, let go of the camera remote. It is then a process of picking through the broken glass in order to setup the next shot.
Here is a closeup of the trigger. I was tempted to build a electronic delay trigger and certainly a sound triggered system may of been easier, but the low tech approach worked too.
So what are the results? Certainly getting there. One thing I learned was the duration of the flash is based on the power. The lower the power the shorter the flash. So I have moved the flash closer and set the camera ISO higher