On 11/4/2009 8:01 AM Jeff Liebermann spake thus:

On Tue, 03 Nov 2009 23:30:22 -0800, David Nebenzahl
wrote:

Yeah; if only we could have desktop printers with feeders as reliable as
the one on the Heidelberg Speedmaster I used to "own" ... now *that's* a
feeder!

Ummm.... su
http://www.heidelberg.com/www/html/en/content/overview1/products/sheetfed_overview-qg
I'm not familiar with it, but my guess is that it uses vacuum pickup
to handle large format and heavy items, such as box cardboard.

Yes. Like most real printing presses (as opposed to smaller "presses"
that are somewhat disparagingly called "duplicators"), the feeder uses
vacuum pickup, assisted by air blowers to separate the top sheets of the
stack. The Heidelberg feeder was pretty cool: it somewhat
counterintuitively picked up the sheet at the *back* and fed it forward.
Really cool to see a "stream" feeder in operation. When properly
adjusted, performs flawlessly.

Still, it might be possible to borrow some of the paper handling
technology and use it for small printers. For example, instead of
pick and plop vacuum paper handling, the feed rollers could use
vacuum to grab, hold, and eventually release the paper.

That would be kewl.

Having seen miniature engines, metal working machinery, and
automobiles, I suspected that someone might build a miniature offset
press that could be adaptable for home use. There's a 1937 patent:
http://www.google.com/patents/about?id=fOo-AAAAEBAJ&dq=2099962
which is not very useful. Google found some vendors in China and
India that sell miniature offset presses. However, their idea of
miniature is about the size of refrigerator. I couldn't find anything
the size of a typical inkjet printer.

Ackshooly, the AB Dick 320 offset duplicator was a table-top model only
slightly larger than the larger laser printers of the early days. I
first learned to print on one of those, using direct paper plates (you
typed and wrote directly on the plate using special ribbons and pencils,
almost like a mimeograph). But the 320, being a dinky "press", used
friction feed (rubber rollers) which of course isn't nearly as good as
vacuum feed.


--
Who needs a junta or a dictatorship when you have a Congress
blowing Wall Street, using the media as a condom?

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