i dont know how old this topic is but i have bought one of these at a lakefront yardsale and sinse tried to paint it (failure) and i have modded it so it shoots faster, farther, more accurate, (working on more comfortable but i have a concept), and sorta rapid fire (dosent work well [but might if ...

To get 1 spark
http://www.advancedspuds.com/1spark.jpg
To get 2 sparks
http://www.advancedspuds.com/2sparks.jpg
To get 3 sparks
http://www.advancedspuds.com/3sparks.jpg
To get 4 sparks
http://www.advancedspuds.com/4sparks.jpg
It makes no difference which is negative and positive ...