PCB artwork and dimensional accuracy

Recently built a CNC setup for the light drilling of PCBs and thin
aluminum. Thought this would have ended all my drilling needs but as
usual one thing leads to another. Problem now is the accuracy of my
favorite laser printer. I could see there were alignment issues when
making double sided boards using artwork from this printer but the
workaround was simply to compromise with the positioning of each side.
Now it's quite obvious that the drilling setup is much more accurate
than the laser output and holes will not be centered as well as hoped
even after making scaling compromises.

With injet printers the results are near perfect but I hate the artwork
from them. Tried both an Epson 785EPX and 2200 with similar
results....Diagonal lines are just too jagged and octagonal pads looks
like crap for example. These are both photo printers (most seem to be
these days) and I'm wondering whether it's possible to get better
graphics from any type of injet printer? What would be the printers of
choice for excellent dimensional accuracy and fine art detail for less
than $1000.00 or even $2000.00? I'm not even interested in color.

 

[Tim Shoppa]

I'm not even interested in color.

Well, then, stop pricing color inkjet printers.

B/W laserjets are good enough for most double-sided layouts. They
often are consistently off-scale by a percent of so in both X and Y,
but it's a "small matter of software" to correct this if it matters.
1% isn't much for a 16-pin through-hole part (0.007 inches over 8 pins)
but it can matter for a 64-pin LCD module for example (0.063 inches
over 64 pins).

Opacity when printing to transparency material can be an issue if you
do photo-exposure... or do you use toner transfer?

Old pen-plotters are the functional equivalent to your CNC setup and
are real cheap.

Tim.

 

I agree with you Matthias

Spoke to Epson yesterday and they recommended the latest drivers and
yes that was the problem. Didn't notice any new high res options in the
menu but the quality is much better now....not on par with the laser,
nevertheless, perfectly acceptable.

 

Have you considered chucking a felt-tip pen into your CNC?

Not that desperate. The latest Epson drivers for the 2200 seems to have
solved my problem with the "jaggies". Printing is also now around ten
times faster for the highest resolution than it was before.

 

Printing from incompatible inks/media
typically have problems such as pin holes, poor density, jagged edges
and poor ink absorption.

None of the inkjets here has a transparency media setting so one has to
choose a media setting that allows the highest resolution to be printed
on transparencies. In other words fool the printer into believing it's
printing on something else. Depending on printer, just choosing any
photopaper media setting may not be the best idea. Any comments on that?