Why does Eagle print everything "thicker"?

On Sat, 24 Mar 2012 14:46:01 +0000, Deniz Can Cigsar wrote:

I tried Eagle 5.11 on Windows XP, 6.1 on Mac Lion, and Windows XP..

Closed all layers but top layer.. The results are the same on Xerox 3140

printer.. Eagle prints everything a little thicker. The pads of MLF

package bridges, and the 10mil lines between SO8 package's pins 1 and 2

tends to bridge to the pin 1.. The calibration is OK, I printed 100mm x

100mm rectangle and its good enough..

 

I printed to pdf, and printed the pdf with Preview application on

macosx, this time the results are much better.. I would say "Oh, I can

do that way" but after comparing it with the same packaging, same size

that Proteus Ares produces, I saw that Proteus produces cleaner

results.. It looks like Eagle widens everything..

 

Should I configure anything other than "calibrate" and "black" options

on printer dialog?

 

Regards,

Deniz

Eagle "prints" just fine to Gerber files, which is what you send off to

the circuit board house.

If you need accurate pdf files, perhaps you should see if you can find a

Gerber file viewer that prints?

--

My liberal friends think I'm a conservative kook.

My conservative friends think I'm a liberal kook.

Why am I not happy that they have found common ground?

Tim Wescott, Communications, Control, Circuits & Software

http://www.wescottdesign.com

I process prototypes myself using photosensitives.. There isn't "one day shipment" choise here.. Because of that I need decent printouts as I am using small packages.

I've been working with Proteus without an issue, however this was surprize to me..

Deniz Can Cigsar wrote:

I tried Eagle 5.11 on Windows XP, 6.1 on Mac Lion, and Windows XP..

Closed all layers but top layer.. The results are the same on Xerox

3140 printer.. Eagle prints everything a little thicker. The pads of

MLF package bridges, and the 10mil lines between SO8 package's pins 1

and 2 tends to bridge to the pin 1.. The calibration is OK, I printed

100mm x 100mm rectangle and its good enough..

 

I printed to pdf, and printed the pdf with Preview application on

macosx, this time the results are much better.. I would say "Oh, I

can do that way" but after comparing it with the same packaging, same

size that Proteus Ares produces, I saw that Proteus produces cleaner

results.. It looks like Eagle widens everything..

 

Should I configure anything other than "calibrate" and "black"

options on printer dialog?

 

Regards,

Deniz

Some thoughts.

Try a print to a printer with a higher resolution.

The Xerox 3140 printer has a native resolution of 600 x 600

The makes each dot 1.66 mil so and 5 mil trace could come out 6.4 mil (28%

larger)

An 8 mil trace would  be 8.3 mil. Closer but still over size.

Those inkjet printing direct to copper laminate accept  1200 dpi  is

required to get the detail faithfully.

The width that a laser printer lays down is impacted by a number of factors;

heat, pressure, amount of toner.

You may have a darkness setting in your driver that if reduced may give the

desired result as less toner is squashed out when it is set with heat and

pressure.

Proteus appears to do something different. Maybe it knows the printer

resolution and thus has the ability to downsize an object so it does not

grow larger than the design size when printed. It would then always be under

size.

I did a test print using an inkjet, replicating your "10mil lines between

SO8 package's pins 1 and 2 tends to bridge to the pin 1"

I get a  trace safely between the pins. But the clearances are less due to

the wet ink spreading out on the surface. (High resolution on Photo glossy

paper)

With an MLF64 the ink spreading nearly closed the spaces between the pads.

More so down the page than across. Again the printer affecting the outcome.

To get a definitive answer as to where the size variation is being

introduced and if whether Eagle does have an issue, a  test print and

accurte measurement would be required.

Hope this helps

Warren

--

Viewed / responded via the newsgroup at

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Deniz Can Cigsar wrote:

I process prototypes myself using photosensitives.. There isn't "one

day shipment" choise here.. Because of that I need decent printouts

as I am using small packages.

 

I've been working with Proteus without an issue, however this was

surprize to me..

After re-reading Tim's suggestion to print from a Gerber viewer I printed

from gerbv

The print is far more realistic (better) than that of Eagles print function

Today's small geometries and printer resolutions seem to be showing up a

deficiency in Eagles code.

Perhaps its time for Cadsoft to revisit the printing code.

Good spotting Deniz

Warren

--

Viewed / responded via the newsgroup at

news.cadsoft.de

Try to print (postscript)negative with the CAM-job, then import the file

into CorelDraw with the option "ps interpreted",  there will be not such an

issue. In german it's called "Tonwertzuwachs" for laser- & inkjet-printers

(I found no english expression for this word, but it's the same as Warren

found out) for printing positive layouts.

r

Thank you Warren..

I forgot to mention that I tried 1200dpi.. The result was the same.. What I think is, on printing directly to the printer, it looks like Eagle uses line drawing routins with some thickness given.. However, PDF and PS are vector formats and the actual drawing is done by the viewer..

I think I'll stick with Proteus.. I didn't liked Eagles libraries, and started redesigning, until I came across the problem.. Most of the components were designed for wave soldering but reflow..

It's also interesting that the PCB software have not advanced much since 1990's.. I still don't see a good candidate to replace "BoardMaker" of those days..

On Sun, 25 Mar 2012 16:39:10 +1200, Warren Brayshaw wrote:

Deniz Can Cigsar wrote:

>> I process prototypes myself using photosensitives.. There isn't "one

>> day shipment" choise here.. Because of that I need decent printouts as

>> I am using small packages.

>>

>> I've been working with Proteus without an issue, however this was

>> surprize to me..

 

After re-reading Tim's suggestion to print from a Gerber viewer I

printed from gerbv

The print is far more realistic (better) than that of Eagles print

function

 

Today's small geometries and printer resolutions seem to be showing up a

deficiency in Eagles code.

Perhaps its time for Cadsoft to revisit the printing code. Good spotting

Deniz

Perhaps the folks at Eagle view the printer stuff as mere documentation

(as do I), and don't lavish it with the attention you'd need if you were

seriously using it to generate artwork.

I frankly don't know if that's the right attitude or not -- but I've

never, ever, seen their Gerbers go astray.

--

Tim Wescott

Control system and signal processing consulting

www.wescottdesign.com

Josef,

It is more than what you mention.. Just put MLF32 on the board and print.. You'll see all the pads will stick together.. The error is more than 0.3mm, which is nothing for a laser printer.. But PS might work if Corell Draw has a correction for that.. Has it?

Tim,

Than it is pity, because it is another thing they didn't pay attention..

1. AFAIK CorelDraw cannot corret PS-data but you can edit them (ungroup/group).

2. I did & I do lots of layouts with the PS_inverted output of the CAM-proc with EAGLE (from V2.6 on) & I had only (initial) probs with the global settings of the DRC. This was often mentioned in the forums, without no reaction from CadSoft :-(

Thouhgt: check the diameter settings in the lbr(s). If they are at "auto" the global DRC rules apply. Changing them to a non-auto diameter will avoid this prob.

HTH

r

Den 24/03/12 15.46, Deniz Can Cigsar skrev:

I tried Eagle 5.11 on Windows XP, 6.1 on Mac Lion, and Windows XP.. Closed all layers but top layer.. The results are the same on Xerox 3140 printer.. Eagle prints everything a little thicker. The pads of MLF package bridges, and the 10mil lines between SO8 package's pins 1 and 2 tends to bridge to the pin 1.. The calibration is OK, I printed 100mm x 100mm rectangle and its good enough..

 

I printed to pdf, and printed the pdf with Preview application on macosx, this time the results are much better.. I would say "Oh, I can do that way" but after comparing it with the same packaging, same size that Proteus Ares produces, I saw that Proteus produces cleaner results.. It looks like Eagle widens everything..

 

Should I configure anything other than "calibrate" and "black" options on printer dialog?

 

When i did toner-transfer PCB's i gave up using a 600 DPI printer.

I bought an Samsung ML2580N which works wonders with toner transfer! -

It has 1200 DPI resolution, so it's usable with finepitch components.

Just my 2 cents.

// Per.