Struggling to come up with a DIY claw component for my project, I considered hacking a cork screw, gear puller or even a golf ball retriever. As luck would have it, I found a commercial medium claw on the web for $25 complete with solenoid (most run for about $185). Since time is of the essence, I sprung for it. However, because it is much larger than I anticipated, I'll have to scrap the inkjet setup. Instead I purchased 4-3/8th inch x 3' rods (zinc) to serve as the rails. I'll still use the DC motors from the printers (12V) to drive the carriage (X-Y). I am having trouble with the claw solenoid. I think it may be 24V. I hooked it up to 12v and it closed but with little power. If I'm lucky it will pick up a crumbled piece of paper. Still thinking what to do about that. Ordered some pulley tires/wheels from KNEX hoping they will ride the 3/8th rod. Started writing some code when I realized that I'll need a mechanism to stop the carriage/truck assembly when it reaches the end of the rail (stop motor). Some people have used a reed/magnetic switch. I might use a momentary switch that will be activated when carriage bumps up against it. So in summary my final box will probably be 3'x3'x3'.