Perforator Musings
By Craig Brougher
Karl Ellison mentioned using an older Epson line printer for a roll punching machine. I would be interested to know what he would use in place of the moveable die plate under the paper? As far as I know, you can't just drill out paper. Also, the paper advance would happen too fast, while a punch was still trying to extract itself. You have to have a stripper plate riding against the top of the paper, too, and that may be impossible. And where would all the paper punchings go? In short order, you wouldn't even be able to FIND your Epson printer, much less watch it work-- providing it could actually still function with all that paper dropping into the machine. And a vacuum will only get a percentage.
On the other hand, who says you have to have a punch and die? I've heard about laser cutters, but I'd think that would not be cost effective. However, an electrical burning tip cutter that arcs into a sole plate might be a fairly painless way to go. The electrode cutter could be continually spinning at, say 10,000 rpm, having a slight bevel at the business end so as not to contact any more than just a point at a time, and made from possibly a conductive ceramic which would not burn away quickly, or tungsten. The reason for this would be so that the arc would trim out each hole cleanly, and not just burn paper with brute energy. With a single point touching the paper, it might work at very reasonable curent levels. There are giant "plasma" cutters that cut through thick steel this way in a very thin line-- almost invisibly. Why not teensy-eeeny-weeny cutters that cut through paper rolls? The advantage is clear: The weight and machinery required, is cut to a very small percentage of that required for mechanical roll punching.
Now for my second suggestion: Instead of just one moveable trolley, why not several? They don't have to be in the same row. they can be parallel to each other across the surface of the paper, and each cutter can be assigned a certain column area of the paper and then timed to consider the fixed offset. That would distribute the load better, it seems to me. Also, it might be arranged to cancel out the sideways forces from the momentum of the trolleys, and the lead errors would be less because the travel distances would be decreased by the same percentage as the number of trolleys taking the load.
Just some crazy musings here, but fun once in awhile, with my pals on MMD. And by the way, I just talked to Bob Streicher who says that building a punch head is easy. He can do one in two weeks. He says the trick is in reading the rolls. He is worried about maintaining a .003" overall accuracy in the reader (wow!). He says that accuracy in the head is "easy." Of course, that guy is good!
Craig.
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(Message sent Sat 19 Oct 1996, 15:24:29 GMT, from time zone GMT.) |
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