Maker Pro
Maker Pro

Create a PCB from an image

L

logjam

Jan 1, 1970
0
I have scans of an unpopulated PC circuit board that I would like to
reproduce using a company that requires Gerber files.

I'm trying to duplicate a S-100 bus card from an Altair 8800 and I want
to preserve the layout for historical accuracy. Is there any "Good"
way to do this? Is there low quantity PCB company out there with an
input file acceptance other than Gerber that would be helpful to me?

I would also like to preserve the font of text items like the logo.

Any suggestions on what I should do would be great.

Thanks,
Grant
 
P

Pooh Bear

Jan 1, 1970
0
logjam said:
I have scans of an unpopulated PC circuit board that I would like to
reproduce using a company that requires Gerber files.

I'm trying to duplicate a S-100 bus card from an Altair 8800 and I want
to preserve the layout for historical accuracy. Is there any "Good"
way to do this? Is there low quantity PCB company out there with an
input file acceptance other than Gerber that would be helpful to me?

I would also like to preserve the font of text items like the logo.

Any suggestions on what I should do would be great.

Is the 'scan' a 'picture' of the pcb ? If so it's only good for reference.
To make a pcb you'll have to recreate the whole thing again from scratch.

Other than Gerber, some outfits may accept certain cad files directly or
you could of course do it the way it certainly was back then and do a tape
up.

Graham
 
L

logjam

Jan 1, 1970
0
The scan is a 300dpi "picture" of the board. With image processing
tools I can get a view of JUST the traces...if that helps.

Are you aware of any PCB programs that will allow you to overlay your
work on top of a picture? That might help me out.

This is a single layer PC board, so it is probably easier than some.
 
J

jibberjabber

Jan 1, 1970
0
If it is to scale you can make one yourself pretty easily and fairly
cheaply.

Press-n-Peel Blue (http://www.techniks.com/) lets you print an image on a
laser printer and iron it onto a blank PCB. I would first bring it into
Photoshop to create a clean black and white (only) image. Don't forget to
also "mirror" the image at this time if needed. Etch it with Ferric
Chloride (from Radio Shack), drill with a Dremel using their cheap PCB bits.
A "wash" with Liquid Tin (Allied Electronics) will protect the traces from
corrosion and make it look much better. Use PnP again on the top (non
copper) side for a silkscreen (it will be black). Do this before drilling
otherwise you won't be able to iron the silk-screen image satisfactorily.
Coat with Polyurethane or acrylic when done.

jj
 
R

Rich Grise

Jan 1, 1970
0
The scan is a 300dpi "picture" of the board. With image processing
tools I can get a view of JUST the traces...if that helps.

Are you aware of any PCB programs that will allow you to overlay your
work on top of a picture? That might help me out.

This is a single layer PC board, so it is probably easier than some.

If you have a laser printer or a copier, there's a technique where you
can take an image of the artwork, either print it on a laser or print
it on a dot-matrix and copy it in a copier, and iron it on to the
board and the toner becomes your resist.

See if you can find a board house that will accept negatives, and
print the artwork precisely 1.000:1.000 on transparency film, and
have them do that.

Single "layer"? Do you mean single "sided"? In S-100?? You just
mean "not multilayer," right?

Good Luck!
Rich
 
J

Jasen Betts

Jan 1, 1970
0
The scan is a 300dpi "picture" of the board. With image processing
tools I can get a view of JUST the traces...if that helps.

Are you aware of any PCB programs that will allow you to overlay your
work on top of a picture? That might help me out.

This is a single layer PC board, so it is probably easier than some.

If it's single sided can you etch from the image you have?
(possibly enhance it a bit in a photo-editing tool like the Gimp
(gimp.org) or photoshop se (Adobe.com) it's not like you need plated
through holes, and there's no alignment issues...

another option may be printing it out on transparency film (possibly
enlarged a bit) and taping it to
your monitor and then re-entering it into a PCB editor. :)

It's computationally difficult to convert raster images to vector
(outline) images, and even harder to convert them to stroked images.
guess which you have and which gerber files are.

Bye.
Jasen
 
L

logjam

Jan 1, 1970
0
Thanks for the suggestions on home grown PCBs. I have done that
before, but Its not "easy" enough for what I want. I need to be able
to easily make these without effort, and the S100 bus card is by far
the simplest. Others will be double sided.

Yes, I meant single sided. :) I can get a copy of the BUS card posted
here.

I have used a PCB program called WinQCad, Protel, CircuitMaker, etc.
Correl draw can trace an image into an HPGL. Is there any chance that
I would find a DXF or HPGL to gerber converter?

Thanks,
Grant
 
P

Pooh Bear

Jan 1, 1970
0
logjam said:
Thanks for the suggestions on home grown PCBs. I have done that
before, but Its not "easy" enough for what I want. I need to be able
to easily make these without effort, and the S100 bus card is by far
the simplest. Others will be double sided.

Yes, I meant single sided. :) I can get a copy of the BUS card posted
here.

I have used a PCB program called WinQCad, Protel, CircuitMaker, etc.
Correl draw can trace an image into an HPGL. Is there any chance that
I would find a DXF or HPGL to gerber converter?

The 'language' of gerbers is something special. The idea of gerber
conversion from a jpg ( or anything else ) is a non-starter. You need a
program that is designed to output gerber data. Other than that the
traditional film approach is the best idea.

Graham
 
L

logjam

Jan 1, 1970
0
So its either film or start from scratch. Are there good DXF to gerber
converters? I'm just trying to find an easy to overlay the new design
over the old.

Film and a drill pattern is what they used in the "old" days?
 
P

Pooh Bear

Jan 1, 1970
0
logjam said:
So its either film or start from scratch. Are there good DXF to gerber
converters?

As I tried to explain there isn't a simple 'conversion'

Gerber is based around commands that flash light onto a photosensitive
film.
http://en.wikipedia.org/wiki/Gerber_File
I'm just trying to find an easy to overlay the new design
over the old.

Film and a drill pattern is what they used in the "old" days?

Manual tape up. Followed by photographic reduction. Drilling for small
quantities was manual.

Graham
 
L

logjam

Jan 1, 1970
0
I found that ViewMate includes the ability to import a bitmap. Does
anyone have this software who could try and see if they could draw on
top of the bitmap? Basically tracing the traces in the image?

The Free version of ViewMate does not allow importing bitmap images.
 
R

Rich Grise

Jan 1, 1970
0
As I tried to explain there isn't a simple 'conversion'

Gerber is based around commands that flash light onto a photosensitive
film.
http://en.wikipedia.org/wiki/Gerber_File


Manual tape up. Followed by photographic reduction. Drilling for small
quantities was manual.

Graham

Yeah! When we were their age, we didn't even have computers! And we
had to walk to school 40 miles through 8' of snow, uphill both ways,
barefoot! ;-)

Cheers!
Rich
 
J

Jasen Betts

Jan 1, 1970
0
Thanks for the suggestions on home grown PCBs. I have done that
before, but Its not "easy" enough for what I want. I need to be able
to easily make these without effort, and the S100 bus card is by far
the simplest. Others will be double sided.

Yes, I meant single sided. :) I can get a copy of the BUS card posted
here.

I have used a PCB program called WinQCad, Protel, CircuitMaker, etc.
Correl draw can trace an image into an HPGL. Is there any chance that
I would find a DXF or HPGL to gerber converter?

DXF is a vector format - it gives outlines of all the dark areas, AIUI
gerber uses the centerline.

I don't know that converting outlines to centrelines is any easier than
converting bitmaps to centrelines.

Bye.
Jasen
 
L

logjam

Jan 1, 1970
0
I'm not that old. ;) I've found quite a few places on the net that do
PCB scanning to gerber file conversion. If the price isn't too bad
then I'll do that. I have to factor in my time involved. If it costs
$200 to scan a PCB then I coudl work an hour over time for a week. ;)\

http://www.westwindcad.com/
http://www.etsind.com/pcbartwork.php
http://www.mhtest.com/scanning.shtml
http://www.scancad.com/ - software/hardware manufacture
http://www.sxlist.com/techref/app/format_conversion.htm - This web page
has instructions for a BMP to gerber conversion, much more work than
mailing the boards to be scanned. ;)
http://www.artnet-tech.com/scan.htm
http://shaaiscanner.com/ - these guys don't have the best grammer on
their site...could be scary to send them an origional card!

I guess the next step is to ask around on usenet who has used one of
these services, what it cost, and how happy they were with the results.
I'm set on making the process automated, that is e-mail a file and get
a board, because otherwise the "project" becomes making boards. ;)

Any ideas on good groups to ask?

Thanks,

Grant
 
R

Rich Webb

Jan 1, 1970
0
DXF is a vector format - it gives outlines of all the dark areas, AIUI
gerber uses the centerline.

I don't know that converting outlines to centrelines is any easier than
converting bitmaps to centrelines.

Corel Trace (and, I'm sure, other similar apps) can do a trace "by
centerline." Tried it out just for grins with a Postscript created by
pcb (from the gEDA family) that I converted to a black'n'white bitmap
by importing it into Corel Draw.

The centerline trace actually looks pretty reasonable when the results
of the bitmap -> vector are brought back into Corel and the line widths
adjusted appropriately.

Corel can save the result as a .dxf file and there are some dxf to
Gerber translators out there (according to Google; haven't tried any).
So it's possible in principle to go from a bitmap to a Gerber via a few
intermediate steps.

I'd be concerned about all the misalignments along the way, though.

The OP's best bet is still probably to load up a board layout package
and create "real" Gerbers. Having a working original board to duplicate
should make it go quickly.
 
J

Jasen Betts

Jan 1, 1970
0
Corel Trace (and, I'm sure, other similar apps) can do a trace "by
centerline." Tried it out just for grins with a Postscript created by
pcb (from the gEDA family) that I converted to a black'n'white bitmap
by importing it into Corel Draw.

hmm, it was about 15 years ago that I last played with corel trace,
The centerline trace actually looks pretty reasonable when the results
of the bitmap -> vector are brought back into Corel and the line widths
adjusted appropriately.

Corel can save the result as a .dxf file and there are some dxf to
Gerber translators out there (according to Google; haven't tried any).
So it's possible in principle to go from a bitmap to a Gerber via a few
intermediate steps.

I'd be concerned about all the misalignments along the way, though.

if a grid was set at 0.1" would that help?
The OP's best bet is still probably to load up a board layout package
and create "real" Gerbers. Having a working original board to duplicate
should make it go quickly.

yeah, probably more time has been spent talking about it.
 
R

Rich Webb

Jan 1, 1970
0
hmm, it was about 15 years ago that I last played with corel trace,

I'd forgotten that I had it. ;-) IIRC, it's now a standard part of the
"Corel Draw" set.
if a grid was set at 0.1" would that help?

Probably not. Many types of individual components are 100 mil pitch but
may well be placed onto a finer grid. Traces almost certainly weren't on
a 100 mil grid even back in the day.

Try printing the result of (bitmap -> centerline trace -> Corel vector
-> dxf -> Gerber) on a transparency and overlaying it onto the original.
If it looks like it's good enough then it might really be so.
yeah, probably more time has been spent talking about it.

The gEDA suite is free and works pretty well (at least under Linux; I
haven't tried it on Windows). If you're ever planning on making
additional boards, you'll need it (or something like it) anyway.
Recreating a "known" board is a good first project.
 
L

logjam

Jan 1, 1970
0
These are the boards I will be copying. I plan on desoldering all the
components, getting the board art duplicated, and then reassembling
them.

http://media.diywelder.com/images4/060101-cpu.jpg

http://media.diywelder.com/images4/060101-1K_static.jpg

In the spirit of getting as much data as possible I will be digitally
x-raying the cards too. The x-rays should make debugging easier since
you can easily see which traces go where via the vias. ;)

Here is a quick and dirty shot of a 68000 chip. The ram chips are in
the top and the PROM are visible in the lower left:
http://media.diywelder.com/images3/090605-512kProcessor.jpg

Here is the RAM section:
http://media.diywelder.com/images3/090605-512kRAM.jpg

For the altair boards they will have no components installed for the
x-ray and I will have adjusted the levels of the picture to provide
less contrast than the above pictures.
 
R

Rich Webb

Jan 1, 1970
0
These are the boards I will be copying. I plan on desoldering all the
components, getting the board art duplicated, and then reassembling
them.

http://media.diywelder.com/images4/060101-cpu.jpg

http://media.diywelder.com/images4/060101-1K_static.jpg

In the spirit of getting as much data as possible I will be digitally
x-raying the cards too. The x-rays should make debugging easier since
you can easily see which traces go where via the vias. ;)

Here is a quick and dirty shot of a 68000 chip. The ram chips are in
the top and the PROM are visible in the lower left:
http://media.diywelder.com/images3/090605-512kProcessor.jpg

Here is the RAM section:
http://media.diywelder.com/images3/090605-512kRAM.jpg

For the altair boards they will have no components installed for the
x-ray and I will have adjusted the levels of the picture to provide
less contrast than the above pictures.

Looks like fun! Good luck -- and also check the 'net for assorted
schematics. A quick check shows that you might be able to find some
out there.
 
L

logjam

Jan 1, 1970
0
A nice thing about the Altair I found is that it came with a complete
set of documentation. I bought it from the 2nd owner, and he has had
it in the basement since 1981 when he got it.
 
Top